Theory Test_Suite_Calculation

section ‹Calculating Sufficient Test Suites›

text ‹This theory describes algorithms to calculate test suites that satisfy the sufficiency
      criterion for a given specification FSM and upper bound m on the number of states in the
      System Under Test.›

theory Test_Suite_Calculation
imports Test_Suite_IO
begin

subsection ‹Calculating Path Prefixes that are to be Extended With Adaptive Cest Cases›

subsubsection ‹Calculating Tests along m-Traversal-Paths›

fun prefix_pair_tests :: "'a ⇒ (('a,'b,'c) traversal_path × ('a set × 'a set)) set ⇒ ('a × ('a,'b,'c) traversal_path × 'a) set" where
  "prefix_pair_tests q pds 
    = ⋃{{(q,p1,(target q p2)), (q,p2,(target q p1))} | p1 p2 . 
          ∃ (p,(rd,dr)) ∈ pds .  
              (p1,p2) ∈ set (prefix_pairs p) ∧ 
              (target q p1) ∈ rd ∧ 
              (target q p2) ∈ rd ∧ 
              (target q p1) ≠ (target q p2)}"

lemma prefix_pair_tests_code[code] :
  "prefix_pair_tests q pds = (⋃(image (λ (p,(rd,dr)) . ⋃ (set (map (λ (p1,p2) . {(q,p1,(target q p2)), (q,p2,(target q p1))}) (filter (λ (p1,p2) . (target q p1) ∈ rd ∧ (target q p2) ∈ rd ∧ (target q p1) ≠ (target q p2)) (prefix_pairs p))))) pds))"
proof -
  have "⋀ tp . tp ∈ prefix_pair_tests q pds ⟹ tp ∈ (⋃(image (λ (p,(rd,dr)) . ⋃ (set (map (λ (p1,p2) . {(q,p1,(target q p2)), (q,p2,(target q p1))}) (filter (λ (p1,p2) . (target q p1) ∈ rd ∧ (target q p2) ∈ rd ∧ (target q p1) ≠ (target q p2)) (prefix_pairs p))))) pds))"
  proof -
    fix tp assume "tp ∈ prefix_pair_tests q pds"
    then obtain tps where "tp ∈ tps"
                    and   "tps ∈ {{(q,p1,(target q p2)), (q,p2,(target q p1))} | p1 p2 . ∃ (p,(rd,dr)) ∈ pds . (p1,p2) ∈ set (prefix_pairs p) ∧ (target q p1) ∈ rd ∧ (target q p2) ∈ rd ∧ (target q p1) ≠ (target q p2)}"
      unfolding prefix_pair_tests.simps
      by (meson UnionE) 
    then obtain p1 p2 where "tps = {(q,p1,(target q p2)), (q,p2,(target q p1))}"
                      and   "∃ (p,(rd,dr)) ∈ pds . (p1,p2) ∈ set (prefix_pairs p) ∧ (target q p1) ∈ rd ∧ (target q p2) ∈ rd ∧ (target q p1) ≠ (target q p2)"
      unfolding mem_Collect_eq by blast

    then obtain p rd dr where "(p,(rd,dr)) ∈ pds" and "(p1,p2) ∈ set (prefix_pairs p)" and "(target q p1) ∈ rd ∧ (target q p2) ∈ rd ∧ (target q p1) ≠ (target q p2)"
      by blast

    have scheme : "⋀ f x xs . x ∈ set xs ⟹ f x ∈ set (map f xs)" 
      by auto

    have "(p1,p2) ∈ set (filter (λ(p1, p2). target q p1 ∈ rd ∧ target q p2 ∈ rd ∧ target q p1 ≠ target q p2) (prefix_pairs p))"
      using ‹(p1,p2) ∈ set (prefix_pairs p)›
            ‹(target q p1) ∈ rd ∧ (target q p2) ∈ rd ∧ (target q p1) ≠ (target q p2)› 
      by auto
    have "{(q,p1,(target q p2)), (q,p2,(target q p1))} ∈ (set (map (λ (p1,p2) . {(q,p1,(target q p2)), (q,p2,(target q p1))}) (filter (λ (p1,p2) . (target q p1) ∈ rd ∧ (target q p2) ∈ rd ∧ (target q p1) ≠ (target q p2)) (prefix_pairs p))))"
      using scheme[OF ‹(p1,p2) ∈ set (filter (λ(p1, p2). target q p1 ∈ rd ∧ target q p2 ∈ rd ∧ target q p1 ≠ target q p2) (prefix_pairs p))›, of "(λ (p1,p2) . {(q,p1,(target q p2)), (q,p2,(target q p1))})"] 
      by simp

    then show "tp ∈ (⋃(image (λ (p,(rd,dr)) . ⋃ (set (map (λ (p1,p2) . {(q,p1,(target q p2)), (q,p2,(target q p1))}) (filter (λ (p1,p2) . (target q p1) ∈ rd ∧ (target q p2) ∈ rd ∧ (target q p1) ≠ (target q p2)) (prefix_pairs p))))) pds))"
      using ‹tp ∈ tps› ‹(p,(rd,dr)) ∈ pds›
      unfolding ‹tps = {(q,p1,(target q p2)), (q,p2,(target q p1))}› 
      by blast
  qed
  moreover have "⋀ tp . tp ∈ (⋃(image (λ (p,(rd,dr)) . ⋃ (set (map (λ (p1,p2) . {(q,p1,(target q p2)), (q,p2,(target q p1))}) (filter (λ (p1,p2) . (target q p1) ∈ rd ∧ (target q p2) ∈ rd ∧ (target q p1) ≠ (target q p2)) (prefix_pairs p))))) pds))
                        ⟹ tp ∈ prefix_pair_tests q pds"
  proof -
    fix tp assume "tp ∈ (⋃(image (λ (p,(rd,dr)) . ⋃ (set (map (λ (p1,p2) . {(q,p1,(target q p2)), (q,p2,(target q p1))}) (filter (λ (p1,p2) . (target q p1) ∈ rd ∧ (target q p2) ∈ rd ∧ (target q p1) ≠ (target q p2)) (prefix_pairs p))))) pds))"
    then obtain prddr where "prddr ∈ pds"
                        and "tp ∈ (λ (p,(rd,dr)) . ⋃ (set (map (λ (p1,p2) . {(q,p1,(target q p2)), (q,p2,(target q p1))}) (filter (λ (p1,p2) . (target q p1) ∈ rd ∧ (target q p2) ∈ rd ∧ (target q p1) ≠ (target q p2)) (prefix_pairs p))))) prddr"
      by blast
    then obtain p rd dr where "prddr = (p,(rd,dr))" by auto

    then have "tp ∈ ⋃ (set (map (λ (p1,p2) . {(q,p1,(target q p2)), (q,p2,(target q p1))}) (filter (λ (p1,p2) . (target q p1) ∈ rd ∧ (target q p2) ∈ rd ∧ (target q p1) ≠ (target q p2)) (prefix_pairs p))))"
      using ‹tp ∈ (λ (p,(rd,dr)) . ⋃ (set (map (λ (p1,p2) . {(q,p1,(target q p2)), (q,p2,(target q p1))}) (filter (λ (p1,p2) . (target q p1) ∈ rd ∧ (target q p2) ∈ rd ∧ (target q p1) ≠ (target q p2)) (prefix_pairs p))))) prddr› by auto

    then obtain p1 p2 where "(p1,p2) ∈ set (filter (λ (p1,p2) . (target q p1) ∈ rd ∧ (target q p2) ∈ rd ∧ (target q p1) ≠ (target q p2)) (prefix_pairs p))"
                      and   "tp ∈ {(q,p1,(target q p2)), (q,p2,(target q p1))}" 
      by auto
    then have "(target q p1) ∈ rd ∧ (target q p2) ∈ rd ∧ (target q p1) ≠ (target q p2)" 
         and  "(p1,p2) ∈ set (prefix_pairs p)"
      by auto

    then show "tp ∈ prefix_pair_tests q pds"
      using ‹prddr ∈ pds› ‹tp ∈ {(q,p1,(target q p2)), (q,p2,(target q p1))}›
      unfolding prefix_pair_tests.simps  ‹prddr = (p,(rd,dr))› 
      by blast
  qed
  ultimately show ?thesis 
    by blast
qed





subsubsection ‹Calculating Tests between Preambles›


fun preamble_prefix_tests' :: "'a ⇒ (('a,'b,'c) traversal_path × ('a set × 'a set)) list ⇒ 'a list ⇒ ('a × ('a,'b,'c) traversal_path × 'a) list" where
  "preamble_prefix_tests' q pds drs = 
    concat (map (λ((p,(rd,dr)),q2,p1) . [(q,p1,q2), (q2,[],(target q p1))]) 
                (filter (λ((p,(rd,dr)),q2,p1) . (target q p1) ∈ rd ∧ q2 ∈ rd ∧ (target q p1) ≠ q2) 
                        (concat (map (λ((p,(rd,dr)),q2) . map (λp1 . ((p,(rd,dr)),q2,p1)) (prefixes p)) (List.product pds drs)))))"


definition preamble_prefix_tests :: "'a ⇒ (('a,'b,'c) traversal_path × ('a set × 'a set)) set ⇒ 'a set ⇒ ('a × ('a,'b,'c) traversal_path × 'a) set" where
  "preamble_prefix_tests q pds drs = ⋃{{(q,p1,q2), (q2,[],(target q p1))} | p1 q2 . ∃ (p,(rd,dr)) ∈ pds . q2 ∈ drs ∧ (∃ p2 . p = p1@p2) ∧ (target q p1) ∈ rd ∧ q2 ∈ rd ∧ (target q p1) ≠ q2}"

lemma preamble_prefix_tests_code[code] :
  "preamble_prefix_tests q pds drs = (⋃(image (λ (p,(rd,dr)) . ⋃(image (λ (p1,q2) . {(q,p1,q2), (q2,[],(target q p1))}) (Set.filter (λ (p1,q2) . (target q p1) ∈ rd ∧ q2 ∈ rd ∧ (target q p1) ≠ q2) ((set (prefixes p)) × drs)))) pds))"
proof -
  have "⋀ pp . pp ∈ preamble_prefix_tests q pds drs ⟹ pp ∈ (⋃(image (λ (p,(rd,dr)) . ⋃(image (λ (p1,q2) . {(q,p1,q2), (q2,[],(target q p1))}) (Set.filter (λ (p1,q2) . (target q p1) ∈ rd ∧ q2 ∈ rd ∧ (target q p1) ≠ q2) ((set (prefixes p)) × drs)))) pds))"  
  proof -
    fix pp assume "pp ∈ preamble_prefix_tests q pds drs"
    then obtain p1 q2 where "pp ∈ {(q,p1,q2), (q2,[],(target q p1))}"
                      and   "∃ (p,(rd,dr)) ∈ pds . q2 ∈ drs ∧ (∃ p2 . p = p1@p2) ∧ (target q p1) ∈ rd ∧ q2 ∈ rd ∧ (target q p1) ≠ q2"
      unfolding preamble_prefix_tests_def by blast
    then obtain p rd dr where "(p,(rd,dr)) ∈ pds" and "q2 ∈ drs" and "(∃ p2 . p = p1@p2)" and "(target q p1) ∈ rd ∧ q2 ∈ rd ∧ (target q p1) ≠ q2"
      by auto

    then have "(p1,q2) ∈ (Set.filter (λ (p1,q2) . (target q p1) ∈ rd ∧ q2 ∈ rd ∧ (target q p1) ≠ q2) ((set (prefixes p)) × drs))"
      unfolding prefixes_set by force
    then show "pp ∈ (⋃(image (λ (p,(rd,dr)) . ⋃(image (λ (p1,q2) . {(q,p1,q2), (q2,[],(target q p1))}) (Set.filter (λ (p1,q2) . (target q p1) ∈ rd ∧ q2 ∈ rd ∧ (target q p1) ≠ q2) ((set (prefixes p)) × drs)))) pds))"
      using ‹(p,(rd,dr)) ∈ pds›
            ‹pp ∈ {(q,p1,q2), (q2,[],(target q p1))}› by blast
  qed
  moreover have "⋀ pp . pp ∈ (⋃(image (λ (p,(rd,dr)) . ⋃(image (λ (p1,q2) . {(q,p1,q2), (q2,[],(target q p1))}) (Set.filter (λ (p1,q2) . (target q p1) ∈ rd ∧ q2 ∈ rd ∧ (target q p1) ≠ q2) ((set (prefixes p)) × drs)))) pds))
                         ⟹ pp ∈ preamble_prefix_tests q pds drs"
  proof -
    fix pp assume "pp ∈ (⋃(image (λ (p,(rd,dr)) . ⋃(image (λ (p1,q2) . {(q,p1,q2), (q2,[],(target q p1))}) (Set.filter (λ (p1,q2) . (target q p1) ∈ rd ∧ q2 ∈ rd ∧ (target q p1) ≠ q2) ((set (prefixes p)) × drs)))) pds))"
    then obtain prddr where "prddr ∈ pds"
                      and   "pp ∈ (λ (p,(rd,dr)) . ⋃(image (λ (p1,q2) . {(q,p1,q2), (q2,[],(target q p1))}) (Set.filter (λ (p1,q2) . (target q p1) ∈ rd ∧ q2 ∈ rd ∧ (target q p1) ≠ q2) ((set (prefixes p)) × drs)))) prddr"
      by blast

    obtain p rd dr where "prddr = (p,(rd,dr))"
      using prod_cases3 by blast 

    obtain p1 q2 where "(p1,q2) ∈ (Set.filter (λ (p1,q2) . (target q p1) ∈ rd ∧ q2 ∈ rd ∧ (target q p1) ≠ q2) ((set (prefixes p)) × drs))"
                 and   "pp ∈ {(q,p1,q2), (q2,[],(target q p1))}"
      using ‹pp ∈ (λ (p,(rd,dr)) . ⋃(image (λ (p1,q2) . {(q,p1,q2), (q2,[],(target q p1))}) (Set.filter (λ (p1,q2) . (target q p1) ∈ rd ∧ q2 ∈ rd ∧ (target q p1) ≠ q2) ((set (prefixes p)) × drs)))) prddr›
      unfolding ‹prddr = (p,(rd,dr))› 
      by blast

    have "q2 ∈ drs ∧ (∃ p2 . p = p1@p2) ∧ (target q p1) ∈ rd ∧ q2 ∈ rd ∧ (target q p1) ≠ q2"
      using ‹(p1,q2) ∈ (Set.filter (λ (p1,q2) . (target q p1) ∈ rd ∧ q2 ∈ rd ∧ (target q p1) ≠ q2) ((set (prefixes p)) × drs))›
      unfolding prefixes_set 
      by auto
    then have "∃(p, rd, dr)∈pds. q2 ∈ drs ∧ (∃p2. p = p1 @ p2) ∧ target q p1 ∈ rd ∧ q2 ∈ rd ∧ target q p1 ≠ q2"
      using ‹prddr ∈ pds› ‹prddr = (p,(rd,dr))› 
      by blast
    then have *: "{(q,p1,q2), (q2,[],(target q p1))} ∈ {{(q, p1, q2), (q2, [], target q p1)} |p1 q2.
             ∃(p, rd, dr)∈pds. q2 ∈ drs ∧ (∃p2. p = p1 @ p2) ∧ target q p1 ∈ rd ∧ q2 ∈ rd ∧ target q p1 ≠ q2}" by blast

    show "pp ∈ preamble_prefix_tests q pds drs"
      using UnionI[OF * ‹pp ∈ {(q,p1,q2), (q2,[],(target q p1))}›]
      unfolding preamble_prefix_tests_def by assumption
  qed
  ultimately show ?thesis by blast
qed



subsubsection "Calculating Tests between m-Traversal-Paths Prefixes and Preambles"

fun preamble_pair_tests :: "'a set set ⇒ ('a × 'a) set ⇒ ('a × ('a,'b,'c) traversal_path × 'a) set" where
  "preamble_pair_tests drss rds = (⋃ drs ∈ drss . (λ (q1,q2) . (q1,[],q2)) ` ((drs × drs) ∩ rds))"





subsection ‹Calculating a Test Suite›


definition calculate_test_paths ::
  "('a,'b,'c) fsm
  ⇒ nat
  ⇒ 'a set
  ⇒ ('a × 'a) set
  ⇒ ('a set × 'a set) list
  ⇒ (('a ⇒ ('a,'b,'c) traversal_path set) × (('a × ('a,'b,'c) traversal_path) ⇒ 'a set))" 
  where
  "calculate_test_paths M m d_reachable_states r_distinguishable_pairs repetition_sets =
    (let
         paths_with_witnesses 
              = (image (λ q . (q,m_traversal_paths_with_witness M q repetition_sets m)) d_reachable_states);
         get_paths                        
              = m2f (set_as_map paths_with_witnesses);
         PrefixPairTests                    
              = ⋃ q ∈ d_reachable_states . ⋃ mrsps ∈ get_paths q . prefix_pair_tests q mrsps;
         PreamblePrefixTests
              = ⋃ q ∈ d_reachable_states . ⋃ mrsps ∈ get_paths q . preamble_prefix_tests q mrsps d_reachable_states;
         PreamblePairTests
              = preamble_pair_tests (⋃ (q,pw) ∈ paths_with_witnesses . ((λ (p,(rd,dr)) . dr) ` pw)) r_distinguishable_pairs;
         tests
              = PrefixPairTests ∪ PreamblePrefixTests ∪ PreamblePairTests; 
         tps'  
              = m2f_by ⋃ (set_as_map (image (λ (q,p) . (q, image fst p)) paths_with_witnesses));
         tps''  
              = m2f (set_as_map (image (λ (q,p,q') . (q,p)) tests));
         tps  
              = (λ q . tps' q ∪ tps'' q);
         rd_targets 
              = m2f (set_as_map (image (λ (q,p,q') . ((q,p),q')) tests))    
  in 
    ( tps, rd_targets ))"


definition combine_test_suite ::
  "('a,'b,'c) fsm
  ⇒ nat
  ⇒ ('a × ('a,'b,'c) preamble) set
  ⇒ (('a × 'a) × (('d,'b,'c) separator × 'd × 'd)) set
  ⇒ ('a set × 'a set) list
  ⇒ ('a,'b,'c,'d) test_suite" 
  where
  "combine_test_suite M m states_with_preambles pairs_with_separators repetition_sets =
    (let drs = image fst states_with_preambles;
        rds = image fst pairs_with_separators;
        tps_and_targets = calculate_test_paths M m drs rds repetition_sets;
        atcs = m2f (set_as_map pairs_with_separators) 
in (Test_Suite states_with_preambles (fst tps_and_targets) (snd tps_and_targets) atcs))"




definition calculate_test_suite_for_repetition_sets :: 
  "('a::linorder,'b::linorder,'c) fsm ⇒ nat ⇒ ('a set × 'a set) list ⇒ ('a,'b,'c, ('a × 'a) + 'a) test_suite" 
  where
  "calculate_test_suite_for_repetition_sets M m repetition_sets = 
    (let
         states_with_preambles = d_reachable_states_with_preambles M;
         pairs_with_separators = image (λ((q1,q2),A) . ((q1,q2),A,Inr q1,Inr q2)) (r_distinguishable_state_pairs_with_separators M)
  in combine_test_suite M m states_with_preambles pairs_with_separators repetition_sets)"




subsection ‹Sufficiency of the Calculated Test Suite›

lemma calculate_test_suite_for_repetition_sets_sufficient_and_finite :
  fixes M :: "('a::linorder,'b::linorder,'c) fsm"
  assumes "observable M"
  and     "completely_specified M"
  and     "inputs M ≠ {}"
  and     "⋀q. q ∈ FSM.states M ⟹ ∃d∈set RepSets. q ∈ fst d"
  and     "⋀d. d ∈ set RepSets ⟹ fst d ⊆ states M ∧ (snd d = fst d ∩ fst ` d_reachable_states_with_preambles M)" 
  and     "⋀ q1 q2 d. d ∈ set RepSets ⟹ q1∈fst d ⟹ q2∈fst d ⟹ q1 ≠ q2 ⟹ (q1, q2) ∈ fst ` r_distinguishable_state_pairs_with_separators M"
shows "implies_completeness (calculate_test_suite_for_repetition_sets M m RepSets) M m"
and   "is_finite_test_suite (calculate_test_suite_for_repetition_sets M m RepSets)"
proof -
  obtain states_with_preambles tps rd_targets atcs where "calculate_test_suite_for_repetition_sets M m RepSets 
                                                          = Test_Suite states_with_preambles tps rd_targets atcs"
    using test_suite.exhaust by blast

  have "⋀ a b c d . Test_Suite states_with_preambles tps rd_targets atcs = Test_Suite a b c d ⟹ tps = b"
    by blast

  have states_with_preambles_def : "states_with_preambles = d_reachable_states_with_preambles M"
    
  
  and tps_def                   : "tps = (λq. (m2f_by ⋃ (set_as_map ((λ(q, p). (q, fst ` p)) ` (λq. (q, m_traversal_paths_with_witness M q RepSets m)) ` fst ` d_reachable_states_with_preambles M))) q
                                            ∪ (m2f (set_as_map ((λ(q, p, q'). (q, p)) `
                                                ((⋃q∈fst ` d_reachable_states_with_preambles M. ⋃ (prefix_pair_tests q ` (m2f (set_as_map ((λq. (q, m_traversal_paths_with_witness M q RepSets m)) ` fst ` d_reachable_states_with_preambles M)) q))) 
                                                ∪ (⋃q∈fst ` d_reachable_states_with_preambles M. ⋃mrsps∈ m2f (set_as_map ((λq. (q, m_traversal_paths_with_witness M q RepSets m)) ` fst ` d_reachable_states_with_preambles M)) q . preamble_prefix_tests q mrsps (fst ` d_reachable_states_with_preambles M)) 
                                                ∪ preamble_pair_tests (⋃(q, y)∈(λq. (q, m_traversal_paths_with_witness M q RepSets m)) ` fst ` d_reachable_states_with_preambles M. (λ(p, rd, dr). dr) ` y) (fst ` (λ((q1, q2), A). ((q1, q2), A, Inr q1 :: 'a × 'a + 'a, Inr q2 :: 'a × 'a + 'a)) ` r_distinguishable_state_pairs_with_separators M))))) q)"
  and rd_targets_def            : "rd_targets = m2f (set_as_map
                                              ((λ(q, p, y). ((q, p), y)) `
                                               ((⋃q∈fst ` d_reachable_states_with_preambles M. ⋃ (prefix_pair_tests q ` (m2f (set_as_map ((λq. (q, m_traversal_paths_with_witness M q RepSets m)) ` fst ` d_reachable_states_with_preambles M)) q))) 
                                               ∪ (⋃q∈fst ` d_reachable_states_with_preambles M. ⋃mrsps∈ m2f (set_as_map ((λq. (q, m_traversal_paths_with_witness M q RepSets m)) ` fst ` d_reachable_states_with_preambles M)) q . preamble_prefix_tests q mrsps (fst ` d_reachable_states_with_preambles M)) 
                                               ∪ preamble_pair_tests (⋃(q, y)∈(λq. (q, m_traversal_paths_with_witness M q RepSets m)) ` fst ` d_reachable_states_with_preambles M. (λ(p, rd, dr). dr) ` y) (fst ` (λ((q1, q2), A). ((q1, q2), A, Inr q1 :: 'a × 'a + 'a, Inr q2 :: 'a × 'a + 'a)) ` r_distinguishable_state_pairs_with_separators M))))"
  and  atcs_def                 : "atcs = m2f (set_as_map ((λ((q1, q2), A). ((q1, q2), A, Inr q1, Inr q2)) ` r_distinguishable_state_pairs_with_separators M))"
    using ‹calculate_test_suite_for_repetition_sets M m RepSets = Test_Suite states_with_preambles tps rd_targets atcs›[symmetric]
    unfolding calculate_test_suite_for_repetition_sets_def combine_test_suite_def Let_def calculate_test_paths_def fst_conv snd_conv by force+
  

  have tps_alt_def: "⋀ q . q ∈ fst ` d_reachable_states_with_preambles M ⟹ 
          tps q = (fst ` m_traversal_paths_with_witness M q RepSets m) ∪ 
                  {z. (q, z)
                    ∈ (λ(q, p, q'). (q, p)) `
                       ((prefix_pair_tests q (m_traversal_paths_with_witness M q RepSets m)) ∪
                        (⋃q∈fst ` d_reachable_states_with_preambles M.
                            ⋃mrsps∈{m_traversal_paths_with_witness M q RepSets m}.
                               preamble_prefix_tests q mrsps (fst ` d_reachable_states_with_preambles M)) ∪
                        preamble_pair_tests (⋃(q, y)∈(λq. (q, m_traversal_paths_with_witness M q RepSets m)) ` fst ` d_reachable_states_with_preambles M. (λ(p, rd, dr). dr) ` y) (fst ` (λ((q1, q2), A). ((q1, q2), A, Inr q1 :: 'a × 'a + 'a, Inr q2 :: 'a × 'a + 'a)) ` r_distinguishable_state_pairs_with_separators M))}"
  and rd_targets_alt_def: "⋀ q p . q ∈ fst ` d_reachable_states_with_preambles M ⟹ 
          rd_targets (q,p) = {z. ((q, p), z)
                   ∈ (λ(q, p, y). ((q, p), y)) `
                      ((prefix_pair_tests q (m_traversal_paths_with_witness M q RepSets m)) ∪
                       (⋃q∈fst ` d_reachable_states_with_preambles M.
                           ⋃mrsps∈{m_traversal_paths_with_witness M q RepSets m}.
                              preamble_prefix_tests q mrsps (fst ` d_reachable_states_with_preambles M)) ∪
                       preamble_pair_tests (⋃(q, y)∈(λq. (q, m_traversal_paths_with_witness M q RepSets m)) ` fst ` d_reachable_states_with_preambles M. (λ(p, rd, dr). dr) ` y) (fst ` (λ((q1, q2), A). ((q1, q2), A, Inr q1 :: 'a × 'a + 'a, Inr q2 :: 'a × 'a + 'a)) ` r_distinguishable_state_pairs_with_separators M))}"
  proof -
    fix q p assume "q ∈ fst ` d_reachable_states_with_preambles M"

  

    have scheme0 : "(case set_as_map
             ((λ(q, p). (q, fst ` p)) `
              (λq. (q, m_traversal_paths_with_witness M q RepSets m)) `
              fst ` d_reachable_states_with_preambles M)
             q of
       None ⇒ ⋃ {} | Some x ⇒ ⋃ x) = image fst (m_traversal_paths_with_witness M q RepSets m)"
    proof -
      have *: "((λ(q, p). (q, fst ` p)) `
              (λq. (q, m_traversal_paths_with_witness M q RepSets m)) `
              fst ` d_reachable_states_with_preambles M)
               = (λ q . (q , image fst (m_traversal_paths_with_witness M q RepSets m))) ` (fst ` d_reachable_states_with_preambles M)"
        by force
      have **: "⋀ f q xs . (case set_as_map
                              ((λq. (q, f q)) ` xs)
                              q of
                        None ⇒ ⋃ {} | Some xs ⇒ ⋃ xs) = (if q ∈ xs then ⋃ {f q} else ⋃ {})" 
      unfolding set_as_map_def by auto

      show ?thesis
        unfolding * **
        using ‹q ∈ fst ` d_reachable_states_with_preambles M›
        by auto
    qed
    
    
    have scheme1 : "⋀ f q xs . (case set_as_map
                              ((λq. (q, f q)) ` xs)
                              q of
                        None ⇒ {} | Some xs ⇒ xs) = (if q ∈ xs then {f q} else {})" 
      unfolding set_as_map_def by auto        


    have scheme2: "(⋃q∈fst ` d_reachable_states_with_preambles M.
                   ⋃ (prefix_pair_tests q `
                       (if q ∈ fst ` d_reachable_states_with_preambles M
                        then {m_traversal_paths_with_witness M q RepSets m} else {})))
      = (⋃q∈fst ` d_reachable_states_with_preambles M. (⋃ (prefix_pair_tests q ` {m_traversal_paths_with_witness M q RepSets m})))"
      unfolding set_as_map_def by auto


    have scheme3: "(⋃q∈fst ` d_reachable_states_with_preambles M.
                   ⋃mrsps∈if q ∈ fst ` d_reachable_states_with_preambles M
                           then {m_traversal_paths_with_witness M q RepSets m} else {}.
                      preamble_prefix_tests q mrsps (fst ` d_reachable_states_with_preambles M))
      = (⋃q∈fst ` d_reachable_states_with_preambles M. (⋃mrsps∈{m_traversal_paths_with_witness M q RepSets m} . preamble_prefix_tests q mrsps (fst ` d_reachable_states_with_preambles M)))"
      unfolding set_as_map_def by auto

    have scheme4 : "(fst ` (λ((q1, q2), A). ((q1, q2), A, Inr q1, Inr q2)) ` r_distinguishable_state_pairs_with_separators M)
                    = image fst (r_distinguishable_state_pairs_with_separators M)" 
      by force

    have *:"tps q = (fst ` m_traversal_paths_with_witness M q RepSets m) ∪ 
                  {z. (q, z)
                    ∈ (λ(q, p, q'). (q, p)) `
                       ((⋃q∈fst ` d_reachable_states_with_preambles M.
                            ⋃ (prefix_pair_tests q ` {m_traversal_paths_with_witness M q RepSets m})) ∪
                        (⋃q∈fst ` d_reachable_states_with_preambles M.
                            ⋃mrsps∈{m_traversal_paths_with_witness M q RepSets m}.
                               preamble_prefix_tests q mrsps (fst ` d_reachable_states_with_preambles M)) ∪
                        preamble_pair_tests (⋃(q, y)∈(λq. (q, m_traversal_paths_with_witness M q RepSets m)) ` fst ` d_reachable_states_with_preambles M. (λ(p, rd, dr). dr) ` y) (fst ` (λ((q1, q2), A). ((q1, q2), A, Inr q1 :: 'a × 'a + 'a, Inr q2 :: 'a × 'a + 'a)) ` r_distinguishable_state_pairs_with_separators M))}"
      unfolding tps_def 
      unfolding scheme0 scheme1 scheme2 scheme3 scheme4
      unfolding set_as_map_def
      by auto

    have **: "{z. (q, z)
                    ∈ (λ(q, p, q'). (q, p)) `
                       ((⋃q∈fst ` d_reachable_states_with_preambles M.
                            ⋃ (prefix_pair_tests q ` {m_traversal_paths_with_witness M q RepSets m})) ∪
                        (⋃q∈fst ` d_reachable_states_with_preambles M.
                            ⋃mrsps∈{m_traversal_paths_with_witness M q RepSets m}.
                               preamble_prefix_tests q mrsps (fst ` d_reachable_states_with_preambles M)) ∪
                        preamble_pair_tests (⋃(q, y)∈(λq. (q, m_traversal_paths_with_witness M q RepSets m)) ` fst ` d_reachable_states_with_preambles M. (λ(p, rd, dr). dr) ` y) (fst ` (λ((q1, q2), A). ((q1, q2), A, Inr q1 :: 'a × 'a + 'a, Inr q2 :: 'a × 'a + 'a)) ` r_distinguishable_state_pairs_with_separators M))}
          = {z. (q, z)
                    ∈ (λ(q, p, q'). (q, p)) `
                       ((prefix_pair_tests q (m_traversal_paths_with_witness M q RepSets m)) ∪
                        (⋃q∈fst ` d_reachable_states_with_preambles M.
                            ⋃mrsps∈{m_traversal_paths_with_witness M q RepSets m}.
                               preamble_prefix_tests q mrsps (fst ` d_reachable_states_with_preambles M)) ∪
                        preamble_pair_tests (⋃(q, y)∈(λq. (q, m_traversal_paths_with_witness M q RepSets m)) ` fst ` d_reachable_states_with_preambles M. (λ(p, rd, dr). dr) ` y) (fst ` (λ((q1, q2), A). ((q1, q2), A, Inr q1 :: 'a × 'a + 'a, Inr q2 :: 'a × 'a + 'a)) ` r_distinguishable_state_pairs_with_separators M))}" 
      (is "{z. (q, z) ∈ ?S1} = {z. (q, z) ∈ ?S2}")
    proof -
      have "⋀ z . (q, z) ∈ ?S1 ⟹ (q, z) ∈ ?S2"
      proof -
        fix z assume "(q, z) ∈ ?S1"
        then consider "(q, z) ∈ (λ(q, p, q'). (q, p)) ` (⋃q∈fst ` d_reachable_states_with_preambles M.
                            ⋃ (prefix_pair_tests q ` {m_traversal_paths_with_witness M q RepSets m}))"
                    | "(q,z) ∈ (λ(q, p, q'). (q, p)) `  (⋃q∈fst ` d_reachable_states_with_preambles M.
                            ⋃mrsps∈{m_traversal_paths_with_witness M q RepSets m}.
                               preamble_prefix_tests q mrsps (fst ` d_reachable_states_with_preambles M))"
                    | "(q,z) ∈ (λ(q, p, q'). (q, p)) ` (preamble_pair_tests (⋃(q, y)∈(λq. (q, m_traversal_paths_with_witness M q RepSets m)) ` fst ` d_reachable_states_with_preambles M. (λ(p, rd, dr). dr) ` y) (fst ` (λ((q1, q2), A). ((q1, q2), A, Inr q1 :: 'a × 'a + 'a, Inr q2 :: 'a × 'a + 'a)) ` r_distinguishable_state_pairs_with_separators M))"
          by blast
        then show "(q, z) ∈ ?S2" proof cases
          case 1
          have scheme: "⋀ f y xs . y ∈ image f xs ⟹ ∃ x . x ∈ xs ∧ f x = y" by auto

          obtain qzq where "qzq ∈ (⋃q∈fst ` d_reachable_states_with_preambles M. ⋃ (prefix_pair_tests q ` {m_traversal_paths_with_witness M q RepSets m}))"
                     and   "(λ(q, p, q'). (q, p)) qzq = (q,z)"
            using scheme[OF 1] by blast
          then obtain q' where "q'∈fst ` d_reachable_states_with_preambles M"
                         and   "qzq ∈ ⋃ (prefix_pair_tests q' ` {m_traversal_paths_with_witness M q' RepSets m})"
            by blast
          then have "fst qzq = q'"
            by auto
          then have "q' = q"
            using ‹(λ(q, p, q'). (q, p)) qzq = (q,z)›
            by (simp add: prod.case_eq_if) 
          then have "qzq ∈ ⋃ (prefix_pair_tests q ` {m_traversal_paths_with_witness M q RepSets m})"
            using ‹qzq ∈ ⋃ (prefix_pair_tests q' ` {m_traversal_paths_with_witness M q' RepSets m})› 
            by blast
          then have "(λ(q, p, q'). (q, p)) qzq ∈ ?S2"
            by auto
          then show ?thesis 
            unfolding ‹(λ(q, p, q'). (q, p)) qzq = (q,z)› 
            by assumption
        next
          case 2 
          then show ?thesis by blast
        next
          case 3
          then show ?thesis by blast
        qed
      qed
      moreover have "⋀ z . (q, z) ∈ ?S2 ⟹ (q, z) ∈ ?S1"
        using ‹q ∈ fst ` d_reachable_states_with_preambles M› by blast
      ultimately show ?thesis
        by meson
    qed

    show "tps q = (fst ` m_traversal_paths_with_witness M q RepSets m) ∪ 
                  {z. (q, z)
                    ∈ (λ(q, p, q'). (q, p)) `
                       ((prefix_pair_tests q (m_traversal_paths_with_witness M q RepSets m)) ∪
                        (⋃q∈fst ` d_reachable_states_with_preambles M.
                            ⋃mrsps∈{m_traversal_paths_with_witness M q RepSets m}.
                               preamble_prefix_tests q mrsps (fst ` d_reachable_states_with_preambles M)) ∪
                        preamble_pair_tests (⋃(q, y)∈(λq. (q, m_traversal_paths_with_witness M q RepSets m)) ` fst ` d_reachable_states_with_preambles M. (λ(p, rd, dr). dr) ` y) (fst ` (λ((q1, q2), A). ((q1, q2), A, Inr q1 :: 'a × 'a + 'a, Inr q2 :: 'a × 'a + 'a)) ` r_distinguishable_state_pairs_with_separators M))}"
     using * unfolding ** by assumption

    have ***: "rd_targets (q,p) = {z. ((q, p), z)
                   ∈ (λ(q, p, y). ((q, p), y)) `
                      ((⋃q∈fst ` d_reachable_states_with_preambles M.
                           ⋃ (prefix_pair_tests q ` {m_traversal_paths_with_witness M q RepSets m})) ∪
                       (⋃q∈fst ` d_reachable_states_with_preambles M.
                           ⋃mrsps∈{m_traversal_paths_with_witness M q RepSets m}.
                              preamble_prefix_tests q mrsps (fst ` d_reachable_states_with_preambles M)) ∪
                       preamble_pair_tests (⋃(q, y)∈(λq. (q, m_traversal_paths_with_witness M q RepSets m)) ` fst ` d_reachable_states_with_preambles M. (λ(p, rd, dr). dr) ` y) (fst ` (λ((q1, q2), A). ((q1, q2), A, Inr q1 :: 'a × 'a + 'a, Inr q2 :: 'a × 'a + 'a)) ` r_distinguishable_state_pairs_with_separators M))}"
      unfolding rd_targets_def
      unfolding scheme1 scheme2 scheme3 scheme4
      unfolding set_as_map_def
      by auto


    have ****: "{z. ((q, p), z)
                   ∈ (λ(q, p, y). ((q, p), y)) `
                      ((⋃q∈fst ` d_reachable_states_with_preambles M.
                           ⋃ (prefix_pair_tests q ` {m_traversal_paths_with_witness M q RepSets m})) ∪
                       (⋃q∈fst ` d_reachable_states_with_preambles M.
                           ⋃mrsps∈{m_traversal_paths_with_witness M q RepSets m}.
                              preamble_prefix_tests q mrsps (fst ` d_reachable_states_with_preambles M)) ∪
                       preamble_pair_tests (⋃(q, y)∈(λq. (q, m_traversal_paths_with_witness M q RepSets m)) ` fst ` d_reachable_states_with_preambles M. (λ(p, rd, dr). dr) ` y) (fst ` (λ((q1, q2), A). ((q1, q2), A, Inr q1 :: 'a × 'a + 'a, Inr q2 :: 'a × 'a + 'a)) ` r_distinguishable_state_pairs_with_separators M))}
          = {z. ((q, p), z)
                   ∈ (λ(q, p, y). ((q, p), y)) `
                      ((prefix_pair_tests q (m_traversal_paths_with_witness M q RepSets m)) ∪
                       (⋃q∈fst ` d_reachable_states_with_preambles M.
                           ⋃mrsps∈{m_traversal_paths_with_witness M q RepSets m}.
                              preamble_prefix_tests q mrsps (fst ` d_reachable_states_with_preambles M)) ∪
                       preamble_pair_tests (⋃(q, y)∈(λq. (q, m_traversal_paths_with_witness M q RepSets m)) ` fst ` d_reachable_states_with_preambles M. (λ(p, rd, dr). dr) ` y) (fst ` (λ((q1, q2), A). ((q1, q2), A, Inr q1 :: 'a × 'a + 'a, Inr q2 :: 'a × 'a + 'a)) ` r_distinguishable_state_pairs_with_separators M))}" 
      (is "{z. ((q, p), z) ∈ ?S1} = {z. ((q, p), z) ∈ ?S2}")
    proof -
      have "⋀ z . ((q, p), z) ∈ ?S1 ⟹ ((q, p), z) ∈ ?S2"
      proof -
        fix z assume "((q, p), z) ∈ ?S1"
        then consider "((q, p), z) ∈ (λ(q, p, y). ((q, p), y)) ` (⋃q∈fst ` d_reachable_states_with_preambles M.
                            ⋃ (prefix_pair_tests q ` {m_traversal_paths_with_witness M q RepSets m}))"
                    | "((q, p), z) ∈ (λ(q, p, y). ((q, p), y)) `  (⋃q∈fst ` d_reachable_states_with_preambles M.
                            ⋃mrsps∈{m_traversal_paths_with_witness M q RepSets m}.
                               preamble_prefix_tests q mrsps (fst ` d_reachable_states_with_preambles M))"
                    | "((q, p), z) ∈ (λ(q, p, y). ((q, p), y)) ` (preamble_pair_tests (⋃(q, y)∈(λq. (q, m_traversal_paths_with_witness M q RepSets m)) ` fst ` d_reachable_states_with_preambles M. (λ(p, rd, dr). dr) ` y) (fst ` (λ((q1, q2), A). ((q1, q2), A, Inr q1 :: 'a × 'a + 'a, Inr q2 :: 'a × 'a + 'a)) ` r_distinguishable_state_pairs_with_separators M))"
          by blast
        then show "((q, p), z) ∈ ?S2" proof cases
          case 1
          have scheme: "⋀ f y xs . y ∈ image f xs ⟹ ∃ x . x ∈ xs ∧ f x = y" by auto

          obtain qzq where "qzq ∈ (⋃q∈fst ` d_reachable_states_with_preambles M. ⋃ (prefix_pair_tests q ` {m_traversal_paths_with_witness M q RepSets m}))"
                     and   "(λ(q, p, y). ((q, p), y)) qzq = ((q,p),z)"
            using scheme[OF 1] by blast
          then obtain q' where "q'∈fst ` d_reachable_states_with_preambles M"
                         and   "qzq ∈ ⋃ (prefix_pair_tests q' ` {m_traversal_paths_with_witness M q' RepSets m})"
            by blast
          then have "fst qzq = q'"
            by auto
          then have "q' = q"
            using ‹(λ(q, p, y). ((q, p), y)) qzq = ((q,p),z)›
            by (simp add: prod.case_eq_if) 
          then have "qzq ∈ ⋃ (prefix_pair_tests q ` {m_traversal_paths_with_witness M q RepSets m})"
            using ‹qzq ∈ ⋃ (prefix_pair_tests q' ` {m_traversal_paths_with_witness M q' RepSets m})› 
            by blast
          then have "(λ(q, p, y). ((q, p), y)) qzq ∈ ?S2"
            by auto
          then show ?thesis 
            unfolding ‹(λ(q, p, y). ((q, p), y)) qzq = ((q,p),z)› 
            by assumption
        next
          case 2 
          then show ?thesis by blast
        next
          case 3
          then show ?thesis by blast
        qed
      qed
      moreover have "⋀ z . ((q, p), z) ∈ ?S2 ⟹ ((q, p), z) ∈ ?S1"
        using ‹q ∈ fst ` d_reachable_states_with_preambles M› by blast
      ultimately show ?thesis
        by meson
    qed

    show "rd_targets (q,p) = {z. ((q, p), z)
                   ∈ (λ(q, p, y). ((q, p), y)) `
                      ((prefix_pair_tests q (m_traversal_paths_with_witness M q RepSets m)) ∪
                       (⋃q∈fst ` d_reachable_states_with_preambles M.
                           ⋃mrsps∈{m_traversal_paths_with_witness M q RepSets m}.
                              preamble_prefix_tests q mrsps (fst ` d_reachable_states_with_preambles M)) ∪
                       preamble_pair_tests (⋃(q, y)∈(λq. (q, m_traversal_paths_with_witness M q RepSets m)) ` fst ` d_reachable_states_with_preambles M. (λ(p, rd, dr). dr) ` y) (fst ` (λ((q1, q2), A). ((q1, q2), A, Inr q1 :: 'a × 'a + 'a, Inr q2 :: 'a × 'a + 'a)) ` r_distinguishable_state_pairs_with_separators M))}"
      using ***  unfolding **** by assumption
  qed


  define pps_alt :: "('a × ('a,'b,'c) traversal_path × 'a) set" where pps_alt_def : "pps_alt = {(q1,[],q2) | q1 q2 . ∃ q p rd dr . q ∈ fst ` d_reachable_states_with_preambles M ∧ (p,(rd,dr)) ∈ m_traversal_paths_with_witness M q RepSets m ∧ q1 ∈ dr ∧ q2 ∈ dr ∧ (q1,q2) ∈ fst  ` r_distinguishable_state_pairs_with_separators M}"
  have preamble_pair_tests_alt :
    "preamble_pair_tests (⋃(q, y)∈(λq. (q, m_traversal_paths_with_witness M q RepSets m)) ` fst ` d_reachable_states_with_preambles M. (λ(p, rd, dr). dr) ` y) (fst ` (λ((q1, q2), A). ((q1, q2), A, Inr q1 :: 'a × 'a + 'a, Inr q2 :: 'a × 'a + 'a)) ` r_distinguishable_state_pairs_with_separators M)
     = pps_alt"
    (is "?PP1 = ?PP2")
  proof -
    have "⋀ x . x ∈ ?PP1 ⟹ x ∈ ?PP2"
    proof -
      fix x assume "x ∈ ?PP1"
      then obtain drs where "drs ∈ (⋃(q, y)∈(λq. (q, m_traversal_paths_with_witness M q RepSets m)) ` fst ` d_reachable_states_with_preambles M. (λ(p, rd, dr). dr) ` y)"
                      and   "x ∈ (λ(q1, q2). (q1, [], q2)) ` (drs × drs ∩ fst ` (λ((q1, q2), A). ((q1, q2), A, Inr q1, Inr q2)) ` r_distinguishable_state_pairs_with_separators M)"
        unfolding preamble_pair_tests.simps by force

      obtain q y where "(q,y) ∈ (λq. (q, m_traversal_paths_with_witness M q RepSets m)) ` fst ` d_reachable_states_with_preambles M"
                 and   "drs ∈ (λ(p, rd, dr). dr) ` y"
        using ‹drs ∈ (⋃(q, y)∈(λq. (q, m_traversal_paths_with_witness M q RepSets m)) ` fst ` d_reachable_states_with_preambles M. (λ(p, rd, dr). dr) ` y)›
        by force

      have "q ∈ fst ` d_reachable_states_with_preambles M"
      and  "y = m_traversal_paths_with_witness M q RepSets m"
        using ‹(q,y) ∈ (λq. (q, m_traversal_paths_with_witness M q RepSets m)) ` fst ` d_reachable_states_with_preambles M›
        by force+

      obtain p rd where "(p,(rd,drs)) ∈ m_traversal_paths_with_witness M q RepSets m"
        using ‹drs ∈ (λ(p, rd, dr). dr) ` y› unfolding ‹y = m_traversal_paths_with_witness M q RepSets m›
        by force


      obtain q1 q2 where "(q1,q2) ∈ (drs × drs ∩ fst ` (λ((q1, q2), A). ((q1, q2), A, Inr q1, Inr q2)) ` r_distinguishable_state_pairs_with_separators M)"
                   and   "x = (q1, [], q2)"
        using ‹x ∈ (λ(q1, q2). (q1, [], q2)) ` (drs × drs ∩ fst ` (λ((q1, q2), A). ((q1, q2), A, Inr q1, Inr q2)) ` r_distinguishable_state_pairs_with_separators M)›
        by force

      have "q1 ∈ drs ∧ q2 ∈ drs ∧ (q1,q2) ∈ fst  ` r_distinguishable_state_pairs_with_separators M"
        using ‹(q1,q2) ∈ (drs × drs ∩ fst ` (λ((q1, q2), A). ((q1, q2), A, Inr q1, Inr q2)) ` r_distinguishable_state_pairs_with_separators M)›
        by force

      then show "x ∈ ?PP2"
        unfolding ‹x = (q1, [], q2)› pps_alt_def
        using ‹q ∈ fst ` d_reachable_states_with_preambles M› ‹(p,(rd,drs)) ∈ m_traversal_paths_with_witness M q RepSets m›
        by blast
    qed

    moreover have "⋀ x . x ∈ ?PP2 ⟹ x ∈ ?PP1" 
    proof -
      fix x assume "x ∈ ?PP2"
      then obtain q1 q2 where "x = (q1,[],q2)" unfolding pps_alt_def
        by auto
      then obtain q p rd dr where "q ∈ fst ` d_reachable_states_with_preambles M" 
                            and   "(p,(rd,dr)) ∈ m_traversal_paths_with_witness M q RepSets m" 
                            and   "q1 ∈ dr ∧ q2 ∈ dr ∧ (q1,q2) ∈ fst  ` r_distinguishable_state_pairs_with_separators M"
        using ‹x ∈ ?PP2› unfolding pps_alt_def by blast

      have "dr ∈ (⋃(q, y)∈(λq. (q, m_traversal_paths_with_witness M q RepSets m)) ` fst ` d_reachable_states_with_preambles M. (λ(p, rd, dr). dr) ` y)"
        using ‹q ∈ fst ` d_reachable_states_with_preambles M› ‹(p,(rd,dr)) ∈ m_traversal_paths_with_witness M q RepSets m› by force

      moreover have "x ∈ (λ(q1, q2). (q1, [], q2)) ` (dr × dr ∩ fst ` (λ((q1, q2), A). ((q1, q2), A, Inr q1, Inr q2)) ` r_distinguishable_state_pairs_with_separators M)"
        unfolding ‹x = (q1,[],q2)› using ‹q1 ∈ dr ∧ q2 ∈ dr ∧ (q1,q2) ∈ fst  ` r_distinguishable_state_pairs_with_separators M› by force

      ultimately show "x ∈ ?PP1"
        unfolding preamble_pair_tests.simps by force
    qed

    ultimately show ?thesis by blast
  qed


  have p1: "(initial M,initial_preamble M) ∈ states_with_preambles"
    using fsm_initial[of M]
    unfolding states_with_preambles_def d_reachable_states_with_preambles_def calculate_state_preamble_from_input_choices.simps by force

  have p2a: "⋀ q P . (q,P) ∈ states_with_preambles ⟹ is_preamble P M q"
    using assms(1) d_reachable_states_with_preambles_soundness(1) states_with_preambles_def by blast

  have p2b: "⋀ q P . (q,P) ∈ states_with_preambles ⟹ (tps q) ≠ {}"
  proof -
    fix q P assume "(q,P) ∈ states_with_preambles"
    then have "q ∈ (image fst (d_reachable_states_with_preambles M))"
      unfolding states_with_preambles_def
      by (simp add: rev_image_eqI) 
    
    have "q ∈ states M"
      using ‹(q, P) ∈ states_with_preambles› assms(1) d_reachable_states_with_preambles_soundness(2) states_with_preambles_def by blast 


    obtain p' d' where  "(p', d') ∈ m_traversal_paths_with_witness M q RepSets m"
      using m_traversal_path_exist[OF assms(2) ‹q ∈ states M› assms(3) ‹⋀q. q ∈ FSM.states M ⟹ ∃d∈set RepSets. q ∈ fst d›] assms(5) 
      by blast
    then have "p' ∈ image fst (m_traversal_paths_with_witness M q RepSets m)"
      using image_iff by fastforce
    
    have "(q, image fst (m_traversal_paths_with_witness M q RepSets m)) ∈ (image (λ (q,p) . (q, image fst p)) (image (λ q . (q,m_traversal_paths_with_witness M q RepSets m)) (image fst (d_reachable_states_with_preambles M))))"
      using ‹q ∈ (image fst (d_reachable_states_with_preambles M))› by force
    have "(image fst (m_traversal_paths_with_witness M q RepSets m)) ∈ (m2f (set_as_map (image (λ (q,p) . (q, image fst p)) (image (λ q . (q,m_traversal_paths_with_witness M q RepSets m)) (image fst (d_reachable_states_with_preambles M)))))) q"
      using set_as_map_containment[OF ‹(q, image fst (m_traversal_paths_with_witness M q RepSets m)) ∈ (image (λ (q,p) . (q, image fst p)) (image (λ q . (q,m_traversal_paths_with_witness M q RepSets m)) (image fst (d_reachable_states_with_preambles M))))›]
      by assumption
    then have "p' ∈ (⋃ ((m2f (set_as_map (image (λ (q,p) . (q, image fst p)) (image (λ q . (q,m_traversal_paths_with_witness M q RepSets m)) (image fst (d_reachable_states_with_preambles M)))))) q))"
      using ‹p' ∈ image fst (m_traversal_paths_with_witness M q RepSets m)› by blast

    then show "(tps q) ≠ {}"
      unfolding tps_def m2f_by_from_m2f by blast
  qed

  have p2: "(∀q P. (q, P) ∈ states_with_preambles ⟶ is_preamble P M q ∧ tps q ≠ {})"
    using p2a p2b by blast

  have "⋀ q1 q2 A d1 d2 . ((A,d1,d2) ∈ atcs (q1,q2)) ⟹ ((q1,q2),A) ∈ r_distinguishable_state_pairs_with_separators M ∧ d1 = Inr q1 ∧ d2 = Inr q2"
  proof -
    fix q1 q2 A d1 d2 assume "((A,d1,d2) ∈ atcs (q1,q2))"
    then have "atcs (q1,q2) = {z. ((q1, q2), z) ∈ (λ((q1, q2), A). ((q1, q2), A, Inr q1, Inr q2)) ` r_distinguishable_state_pairs_with_separators M}"
      unfolding atcs_def set_as_map_def by auto
    then show "((q1,q2),A) ∈ r_distinguishable_state_pairs_with_separators M ∧ d1 = Inr q1 ∧ d2 = Inr q2"
      using ‹((A,d1,d2) ∈ atcs (q1,q2))› by auto
  qed


  have "⋀ q1 q2 A d1 d2 . (A,d1,d2) ∈ atcs (q1,q2) ⟹ (A,d2,d1) ∈ atcs (q2,q1) ∧ is_separator M q1 q2 A d1 d2"
  proof -
    fix q1 q2 A d1 d2 assume "(A,d1,d2) ∈ atcs (q1,q2)"
    then have "((q1,q2),A) ∈ r_distinguishable_state_pairs_with_separators M" and "d1 = Inr q1" and "d2 = Inr q2"
      using ‹⋀ q1 q2 A d1 d2 . ((A,d1,d2) ∈ atcs (q1,q2)) ⟹ ((q1,q2),A) ∈ r_distinguishable_state_pairs_with_separators M ∧ d1 = Inr q1 ∧ d2 = Inr q2›
      by blast+
    then have "((q2,q1),A) ∈ r_distinguishable_state_pairs_with_separators M"
      unfolding r_distinguishable_state_pairs_with_separators_def
      by auto  
    then have "(A,d2,d1) ∈ atcs (q2,q1)"
      unfolding atcs_def ‹d1 = Inr q1› ‹d2 = Inr q2› set_as_map_def by force
    moreover have "is_separator M q1 q2 A d1 d2"
      using r_distinguishable_state_pairs_with_separators_elem_is_separator[OF ‹((q1,q2),A) ∈ r_distinguishable_state_pairs_with_separators M› assms(1,2)]
      unfolding ‹d1 = Inr q1› ‹d2 = Inr q2›
      by assumption
    ultimately show "(A,d2,d1) ∈ atcs (q2,q1) ∧ is_separator M q1 q2 A d1 d2"
      by simp
  qed
  then have p3 : "(∀q1 q2 A d1 d2. (A, d1, d2) ∈ atcs (q1, q2) ⟶ (A, d2, d1) ∈ atcs (q2, q1) ∧ is_separator M q1 q2 A d1 d2)"
    by blast

  have p4: "⋀ q . q ∈ states M ⟹ (∃d ∈ set RepSets. q ∈ fst d)"
    by (simp add: assms(4))
  
  have p5: "⋀ d . d ∈ set RepSets ⟹ ((fst d ⊆ states M) ∧ (snd d = fst d ∩ fst ` states_with_preambles) ∧ (∀ q1 q2 . q1 ∈ fst d ⟶ q2 ∈ fst d ⟶ q1 ≠ q2 ⟶ atcs (q1,q2) ≠ {}))"
  proof -
    fix d assume "d ∈ set RepSets"
    
    then have "⋀ q1 q2 . q1 ∈ fst d ⟹ q2 ∈ fst d ⟹ q1 ≠ q2 ⟹ atcs (q1,q2) ≠ {}"
    proof -
      fix q1 q2 assume "q1 ∈ fst d" and "q2 ∈ fst d" and "q1 ≠ q2"
      then have "(q1, q2) ∈ fst ` r_distinguishable_state_pairs_with_separators M" 
        using assms(6)[OF ‹d ∈ set RepSets›] by blast
      then obtain A where "((q1,q2),A) ∈ r_distinguishable_state_pairs_with_separators M"
        by auto
      then have "(A,Inr q1,Inr q2) ∈ atcs (q1,q2)"
        unfolding atcs_def set_as_map_def 
        by force
      then show "atcs (q1,q2) ≠ {}"
        by blast
    qed
    then show "((fst d ⊆ states M) ∧ (snd d = fst d ∩ fst ` states_with_preambles) ∧ (∀ q1 q2 . q1 ∈ fst d ⟶ q2 ∈ fst d ⟶ q1 ≠ q2 ⟶ atcs (q1,q2) ≠ {}))"
      using assms(5)[OF ‹d ∈ set RepSets›] unfolding states_with_preambles_def by blast
  qed

  have p6 : "⋀ q . q ∈ image fst states_with_preambles ⟹ tps q ⊆ {p1 . ∃ p2 d . (p1@p2,d) ∈ m_traversal_paths_with_witness M q RepSets m} ∧ fst ` (m_traversal_paths_with_witness M q RepSets m) ⊆ tps q"
  proof 
    fix q assume "q ∈ image fst states_with_preambles"
    then have "q ∈ fst ` d_reachable_states_with_preambles M"
      unfolding states_with_preambles_def by assumption
    then have "q ∈ states M"
      by (metis (no_types, lifting) assms(1) d_reachable_states_with_preambles_soundness(2) image_iff prod.collapse)
    show "fst ` m_traversal_paths_with_witness M q RepSets m ⊆ tps q"
      unfolding tps_alt_def[OF ‹q ∈ fst ` d_reachable_states_with_preambles M›]
      by blast


    show "tps q ⊆ {p1 . ∃ p2 d . (p1@p2,d) ∈ m_traversal_paths_with_witness M q RepSets m}"
    proof
      fix p assume "p ∈ tps q"


      have * : "(⋀ q . q ∈ states M ⟹ (∃d ∈ set RepSets. q ∈ fst d))" 
        using p4 by blast

      have  **: "(⋀ d . d ∈ set RepSets ⟹ (snd d ⊆ fst d))"
        using p5 by simp

      from ‹p ∈ tps q› consider 
        (a) "p ∈ fst ` m_traversal_paths_with_witness M q RepSets m" |
        (b) "(q, p) ∈ (λ(q, p, q'). (q, p)) ` (prefix_pair_tests q (m_traversal_paths_with_witness M q RepSets m))" |
        (c) "(q, p) ∈ (λ(q, p, q'). (q, p)) ` (⋃q∈fst ` d_reachable_states_with_preambles M.
                ⋃mrsps∈{m_traversal_paths_with_witness M q RepSets m}.
                   preamble_prefix_tests q mrsps (fst ` d_reachable_states_with_preambles M))" |
        (d) "(q, p) ∈ (λ(q, p, q'). (q, p)) ` pps_alt"  
        unfolding tps_alt_def[OF ‹q ∈ fst ` d_reachable_states_with_preambles M›] preamble_pair_tests_alt by blast

      then show "p ∈ {p1. ∃p2 d. (p1 @ p2, d) ∈ m_traversal_paths_with_witness M q RepSets m}"
      proof cases
        case a
        then obtain d where "(p,d) ∈ m_traversal_paths_with_witness M q RepSets m"
          by auto
        then have "∃p2 d. (p @ p2, d) ∈ m_traversal_paths_with_witness M q RepSets m"
          by (metis append_eq_append_conv2)
        then show ?thesis 
          by blast
      next
        case b
  
        obtain p1 p2  where "(q,p) ∈ ((λ(q, p, q'). (q, p)) `{(q, p1, target q p2), (q, p2, target q p1)})"
           and "∃(p, rd, dr)∈m_traversal_paths_with_witness M q RepSets m.
              (p1, p2) ∈ set (prefix_pairs p) ∧ target q p1 ∈ rd ∧ target q p2 ∈ rd ∧ target q p1 ≠ target q p2"
          using b
          unfolding prefix_pair_tests.simps by blast
  
        obtain p' d where "(p', d) ∈ m_traversal_paths_with_witness M q RepSets m"
                    and   "(p1, p2) ∈ set (prefix_pairs p')"
          using ‹∃(p, rd, dr)∈m_traversal_paths_with_witness M q RepSets m.
              (p1, p2) ∈ set (prefix_pairs p) ∧ target q p1 ∈ rd ∧ target q p2 ∈ rd ∧ target q p1 ≠ target q p2›
          by blast
  
        have "∃ p'' . p' = p @ p''"
          using ‹(p1, p2) ∈ set (prefix_pairs p')› unfolding prefix_pairs_set_alt 
          using ‹(q,p) ∈ ((λ(q, p, q'). (q, p)) `{(q, p1, target q p2), (q, p2, target q p1)})› by auto
        then show ?thesis
          using ‹(p', d) ∈ m_traversal_paths_with_witness M q RepSets m›  
          by blast
      next
        case c     
  
        obtain q' where "q' ∈ fst ` d_reachable_states_with_preambles M"
                  and   "(q,p) ∈ (λ(q, p, q'). (q, p)) ` (preamble_prefix_tests q' (m_traversal_paths_with_witness M q' RepSets m) (fst ` d_reachable_states_with_preambles M))"
          using c by blast
  
        obtain p1 q2  where "(q,p) ∈ ((λ(q, p, q'). (q, p)) `{(q', p1, q2), (q2, [], target q' p1)})"
           and "∃(p, rd, dr)∈m_traversal_paths_with_witness M q' RepSets m.
              q2 ∈ fst ` d_reachable_states_with_preambles M ∧ (∃p2. p = p1 @ p2) ∧ target q' p1 ∈ rd ∧ q2 ∈ rd ∧ target q' p1 ≠ q2"
          using ‹(q,p) ∈ (λ(q, p, q'). (q, p)) ` (preamble_prefix_tests q' (m_traversal_paths_with_witness M q' RepSets m) (fst ` d_reachable_states_with_preambles M))›
          unfolding preamble_prefix_tests_def
          by blast
  
        obtain p2 d where "(p1@p2, d)∈m_traversal_paths_with_witness M q' RepSets m"
                        and   "q2 ∈ fst ` d_reachable_states_with_preambles M"
          using ‹∃(p, rd, dr)∈m_traversal_paths_with_witness M q' RepSets m.
              q2 ∈ fst ` d_reachable_states_with_preambles M ∧ (∃p2. p = p1 @ p2) ∧ target q' p1 ∈ rd ∧ q2 ∈ rd ∧ target q' p1 ≠ q2›
          by blast
  
        consider (a) "q = q' ∧ p = p1" | (b) "q = q2 ∧ p = []"
          using ‹(q,p) ∈ ((λ(q, p, q'). (q, p)) `{(q', p1, q2), (q2, [], target q' p1)})› by auto
        then show ?thesis proof cases
          case a
          then show ?thesis
            using ‹(p1 @ p2, d) ∈ m_traversal_paths_with_witness M q' RepSets m› by blast 
  
        next
          case b
  
          then have "q ∈ states M" and "p = []"
            using ‹q2 ∈ fst ` d_reachable_states_with_preambles M› unfolding d_reachable_states_with_preambles_def by auto
  
          have "∃p' d'. (p', d') ∈ m_traversal_paths_with_witness M q RepSets m"
            using m_traversal_path_exist[OF assms(2) ‹q ∈ states M› assms(3) * **]
            by blast
          then show ?thesis 
            unfolding ‹p = []›
            by simp
        qed
      next
        case d 
        then have "p = []" 
          unfolding pps_alt_def by force
        
        have "q ∈ states M"
          using ‹q ∈ fst ` d_reachable_states_with_preambles M› unfolding d_reachable_states_with_preambles_def by auto
  
        have "∃p' d'. (p', d') ∈ m_traversal_paths_with_witness M q RepSets m"
          using m_traversal_path_exist[OF assms(2) ‹q ∈ states M› assms(3) * **]
          by blast
        then show ?thesis 
          unfolding ‹p = []›
          by simp
      qed
    qed
  qed
 
  have p7 : "⋀ q p d . q ∈ image fst states_with_preambles ⟹ (p,d) ∈ m_traversal_paths_with_witness M q RepSets m ⟹ 
            ( (∀ p1 p2 p3 . p=p1@p2@p3 ⟶ p2 ≠ [] ⟶ target q p1 ∈ fst d ⟶ target q (p1@p2) ∈ fst d ⟶ target q p1 ≠ target q (p1@p2) ⟶ (p1 ∈ tps q ∧ (p1@p2) ∈ tps q ∧ target q p1 ∈ rd_targets (q,(p1@p2)) ∧ target q (p1@p2) ∈ rd_targets (q,p1)))
            ∧ (∀ p1 p2 q' . p=p1@p2 ⟶ q' ∈ image fst states_with_preambles ⟶ target q p1 ∈ fst d ⟶ q' ∈ fst d ⟶ target q p1 ≠ q' ⟶ (p1 ∈ tps q ∧ [] ∈ tps q' ∧ target q p1 ∈ rd_targets (q',[]) ∧ q' ∈ rd_targets (q,p1)))
            ∧ (∀ q1 q2 . q1 ≠ q2 ⟶ q1 ∈ snd d ⟶ q2 ∈ snd d ⟶ ([] ∈ tps q1 ∧ [] ∈ tps q2 ∧ q1 ∈ rd_targets (q2,[]) ∧ q2 ∈ rd_targets (q1,[]))))"
  proof -
    fix q p d assume "q ∈ image fst states_with_preambles" and "(p,d) ∈ m_traversal_paths_with_witness M q RepSets m"
    then have "(p,(fst d, snd d)) ∈ m_traversal_paths_with_witness M q RepSets m" by auto

    have "q ∈ fst ` d_reachable_states_with_preambles M"
      using ‹q ∈ image fst states_with_preambles› unfolding states_with_preambles_def by assumption

    have p7c1 : "⋀ p1 p2 p3 . p=p1@p2@p3 ⟹ p2 ≠ [] ⟹ target q p1 ∈ fst d ⟹ target q (p1@p2) ∈ fst d ⟹ target q p1 ≠ target q (p1@p2) ⟹ (p1 ∈ tps q ∧ (p1@p2) ∈ tps q ∧ target q p1 ∈ rd_targets (q,(p1@p2)) ∧ target q (p1@p2) ∈ rd_targets (q,p1))"
    proof -
      fix p1 p2 p3 assume "p=p1@p2@p3" and "p2 ≠ []" and "target q p1 ∈ fst d" and "target q (p1@p2) ∈ fst d" and "target q p1 ≠ target q (p1@p2)"

      have "(p1,p1@p2) ∈ set (prefix_pairs p)"
        using ‹p=p1@p2@p3› ‹p2 ≠ []› unfolding prefix_pairs_set
        by simp 
      then have "(p1,p1@p2) ∈ set (filter (λ(p1, p2). target q p1 ∈ fst d ∧ target q p2 ∈ fst d ∧ target q p1 ≠ target q p2) (prefix_pairs p))"
        using ‹target q p1 ∈ fst d› ‹target q (p1@p2) ∈ fst d› ‹target q p1 ≠ target q (p1@p2)›
        by auto
      have "{(q, p1, target q (p1@p2)), (q, (p1@p2), target q p1)} ∈ ((set (map (λ(p1, p2). {(q, p1, target q p2), (q, p2, target q p1)})
            (filter (λ(p1, p2). target q p1 ∈ fst d ∧ target q p2 ∈ fst d ∧ target q p1 ≠ target q p2) (prefix_pairs p)))))"
        using map_set[OF ‹(p1,p1@p2) ∈ set (filter (λ(p1, p2). target q p1 ∈ fst d ∧ target q p2 ∈ fst d ∧ target q p1 ≠ target q p2) (prefix_pairs p))›, of "(λ(p1, p2). {(q, p1, target q p2), (q, p2, target q p1)})"] 
        by force
      then have "(q, p1, target q (p1@p2)) ∈ prefix_pair_tests q (m_traversal_paths_with_witness M q RepSets m)"
           and  "(q, p1@p2, target q p1) ∈ prefix_pair_tests q (m_traversal_paths_with_witness M q RepSets m)"
        unfolding prefix_pair_tests_code[of q "m_traversal_paths_with_witness M q RepSets m"]
        using ‹(p,(fst d, snd d)) ∈ m_traversal_paths_with_witness M q RepSets m›
        by blast+

      have "p1 ∈ tps q"
      proof -
        have "(q, p1) ∈ ((λ(q, p, q'). (q, p)) ` (prefix_pair_tests q (m_traversal_paths_with_witness M q RepSets m)))"
          using ‹(q, p1, target q (p1@p2)) ∈ prefix_pair_tests q (m_traversal_paths_with_witness M q RepSets m)›
          by (simp add: rev_image_eqI)  
        then show ?thesis 
          unfolding tps_alt_def[OF ‹q ∈ fst ` d_reachable_states_with_preambles M›] 
          by blast
      qed

      moreover have "(p1@p2) ∈ tps q"
      proof -
        have "(q, p1@p2) ∈ ((λ(q, p, q'). (q, p)) ` (prefix_pair_tests q (m_traversal_paths_with_witness M q RepSets m)))"
          using ‹(q, p1@p2, target q p1) ∈ prefix_pair_tests q (m_traversal_paths_with_witness M q RepSets m)›
          by (simp add: rev_image_eqI) 
        then show ?thesis 
          unfolding tps_alt_def[OF ‹q ∈ fst ` d_reachable_states_with_preambles M›] 
          by blast          
      qed

      moreover have "target q p1 ∈ rd_targets (q,(p1@p2))"
      proof -
        have "((q, p1@p2), target q p1) ∈ (λ(q, p, y). ((q, p), y)) ` prefix_pair_tests q (m_traversal_paths_with_witness M q RepSets m)"
          using ‹(q, p1@p2, target q p1) ∈ prefix_pair_tests q (m_traversal_paths_with_witness M q RepSets m)›
          by (simp add: rev_image_eqI)
        then show ?thesis
          unfolding rd_targets_alt_def[OF ‹q ∈ fst ` d_reachable_states_with_preambles M›] 
          by blast
      qed

      moreover have "target q (p1@p2) ∈ rd_targets (q,p1)"
      proof -
        have "((q, p1), target q (p1@p2)) ∈ (λ(q, p, y). ((q, p), y)) ` prefix_pair_tests q (m_traversal_paths_with_witness M q RepSets m)"
          using ‹(q, p1, target q (p1@p2)) ∈ prefix_pair_tests q (m_traversal_paths_with_witness M q RepSets m)›
          by (simp add: rev_image_eqI)
        then show ?thesis
          unfolding rd_targets_alt_def[OF ‹q ∈ fst ` d_reachable_states_with_preambles M›] 
          by blast
      qed
      
      ultimately show "(p1 ∈ tps q ∧ (p1@p2) ∈ tps q ∧ target q p1 ∈ rd_targets (q,(p1@p2)) ∧ target q (p1@p2) ∈ rd_targets (q,p1))"
        by blast
    qed

    moreover have p7c2: "⋀ p1 p2 q' . p=p1@p2 ⟹ q' ∈ image fst states_with_preambles ⟹ target q p1 ∈ fst d ⟹ q' ∈ fst d ⟹ target q p1 ≠ q' ⟹ (p1 ∈ tps q ∧ [] ∈ tps q' ∧ target q p1 ∈ rd_targets (q',[]) ∧ q' ∈ rd_targets (q,p1))"
    proof -
      fix p1 p2 q' assume "p=p1@p2" and "q' ∈ image fst states_with_preambles" and "target q p1 ∈ fst d" and "q' ∈ fst d" and "target q p1 ≠ q'"
      then have "q' ∈ fst ` d_reachable_states_with_preambles M"
        unfolding states_with_preambles_def by blast
      
      have "p1 ∈ set (prefixes p)"
        using ‹p=p1@p2› unfolding prefixes_set
        by simp 
      then have "(p1,q') ∈ Set.filter (λ(p1, q2). target q p1 ∈ fst d ∧ q2 ∈ fst d ∧ target q p1 ≠ q2) (set (prefixes p) × fst ` d_reachable_states_with_preambles M)"
        using ‹target q p1 ∈ fst d› ‹q' ∈ fst d› ‹q' ∈ image fst states_with_preambles› ‹target q p1 ≠ q'› unfolding states_with_preambles_def
        by force
      then have "{(q, p1, q'), (q', [], target q p1)} ⊆ preamble_prefix_tests q (m_traversal_paths_with_witness M q RepSets m) (fst ` d_reachable_states_with_preambles M)"
        using preamble_prefix_tests_code[of q "m_traversal_paths_with_witness M q RepSets m" "(fst ` d_reachable_states_with_preambles M)"]
        using ‹(p,(fst d, snd d)) ∈ m_traversal_paths_with_witness M q RepSets m›
        by blast
      then have "(q, p1, q') ∈ preamble_prefix_tests q (m_traversal_paths_with_witness M q RepSets m) (fst ` d_reachable_states_with_preambles M)"
           and  "(q', [], target q p1) ∈ preamble_prefix_tests q (m_traversal_paths_with_witness M q RepSets m) (fst ` d_reachable_states_with_preambles M)"
        by blast+

      have "p1 ∈ tps q"
        using ‹(q, p1, q') ∈ preamble_prefix_tests q (m_traversal_paths_with_witness M q RepSets m) (fst ` d_reachable_states_with_preambles M)›        
              ‹q ∈ fst ` d_reachable_states_with_preambles M›
        unfolding tps_alt_def[OF ‹q ∈ fst ` d_reachable_states_with_preambles M›]
        by force

      moreover have "[] ∈ tps q'"
        using ‹(q', [], target q p1) ∈ preamble_prefix_tests q (m_traversal_paths_with_witness M q RepSets m) (fst ` d_reachable_states_with_preambles M)›        
              ‹q ∈ fst ` d_reachable_states_with_preambles M›
        unfolding tps_alt_def[OF ‹q' ∈ fst ` d_reachable_states_with_preambles M›]
        by force

      moreover have "target q p1 ∈ rd_targets (q',[])"
        using ‹(q', [], target q p1) ∈ preamble_prefix_tests q (m_traversal_paths_with_witness M q RepSets m) (fst ` d_reachable_states_with_preambles M)›        
              ‹q ∈ fst ` d_reachable_states_with_preambles M›
        unfolding rd_targets_alt_def[OF ‹q' ∈ fst ` d_reachable_states_with_preambles M›] 
        by force

      moreover have "q' ∈ rd_targets (q,p1)"
        using ‹(q, p1, q') ∈ preamble_prefix_tests q (m_traversal_paths_with_witness M q RepSets m) (fst ` d_reachable_states_with_preambles M)›        
              ‹q ∈ fst ` d_reachable_states_with_preambles M›
        unfolding rd_targets_alt_def[OF ‹q ∈ fst ` d_reachable_states_with_preambles M›]
        by force

      ultimately show "(p1 ∈ tps q ∧ [] ∈ tps q' ∧ target q p1 ∈ rd_targets (q',[]) ∧ q' ∈ rd_targets (q,p1))"
        by blast
    qed


    moreover have p7c3: "⋀ q1 q2 . q1 ≠ q2 ⟹ q1 ∈ snd d ⟹ q2 ∈ snd d ⟹ ([] ∈ tps q1 ∧ [] ∈ tps q2 ∧ q1 ∈ rd_targets (q2,[]) ∧ q2 ∈ rd_targets (q1,[]))"
    proof -
      fix q1 q2 assume "q1 ≠ q2" and "q1 ∈ snd d" and "q2 ∈ snd d"

      have "(⋀d. d ∈ set RepSets ⟹ snd d ⊆ fst d)"
        using p5 by blast
      have "q ∈ states M"
        by (metis (no_types, lifting) ‹q ∈ fst ` d_reachable_states_with_preambles M› assms(1) 
              d_reachable_states_with_preambles_soundness(2) image_iff prod.collapse) 

      have "d ∈ set RepSets" 
        using m_traversal_paths_with_witness_set[OF p4 ‹(⋀d. d ∈ set RepSets ⟹ snd d ⊆ fst d)› ‹q ∈ states M›, of m]
        using ‹(p, d) ∈ m_traversal_paths_with_witness M q RepSets m› find_set 
        by force 

      have "fst d ⊆ states M" 
      and  "snd d = fst d ∩ fst ` states_with_preambles" 
      and  "⋀ q1 q2. q1 ∈ fst d ⟹ q2 ∈ fst d ⟹ q1 ≠ q2 ⟹ atcs (q1, q2) ≠ {}"
        using p5[OF ‹d ∈ set RepSets›] by blast+

      have "q1 ∈ fst d" 
       and "q2 ∈ fst d" 
       and "q1 ∈ fst ` d_reachable_states_with_preambles M" 
       and "q2 ∈ fst ` d_reachable_states_with_preambles M"
        using ‹q1 ∈ snd d› ‹q2 ∈ snd d› unfolding ‹snd d = fst d ∩ fst ` states_with_preambles› 
        unfolding states_with_preambles_def by blast+

      obtain A t1 t2 where "(A,t1,t2) ∈ atcs (q1, q2)"
        using ‹⋀ q1 q2. q1 ∈ fst d ⟹ q2 ∈ fst d ⟹ q1 ≠ q2 ⟹ atcs (q1, q2) ≠ {}›[OF ‹q1 ∈ fst d› ‹q2 ∈ fst d› ‹q1 ≠ q2›] 
        by auto

      then have "(q1, q2) ∈ fst ` r_distinguishable_state_pairs_with_separators M" 
        unfolding atcs_def using set_as_map_elem by force
      then have "(q1,[],q2) ∈ pps_alt"
        using ‹q ∈ fst ` d_reachable_states_with_preambles M› ‹(p,(fst d, snd d)) ∈ m_traversal_paths_with_witness M q RepSets m›
        unfolding pps_alt_def
        by (metis (mono_tags, lifting) ‹q1 ∈ snd d› ‹q2 ∈ snd d› mem_Collect_eq) 
      then have "[] ∈ tps q1" and "q2 ∈ rd_targets (q1,[])"
        unfolding tps_alt_def[OF ‹q1 ∈ fst ` d_reachable_states_with_preambles M›] 
                  rd_targets_alt_def[OF ‹q1 ∈ fst ` d_reachable_states_with_preambles M›] 
                  preamble_pair_tests_alt 
        by force+

      have "(A,t2,t1) ∈ atcs (q2, q1)"
        using p3 ‹(A,t1,t2) ∈ atcs (q1, q2)› by blast
      then have "(q2, q1) ∈ fst ` r_distinguishable_state_pairs_with_separators M" 
        unfolding atcs_def using set_as_map_elem by force
      then have "(q2,[],q1) ∈ pps_alt"
        using ‹q ∈ fst ` d_reachable_states_with_preambles M› ‹(p,(fst d, snd d)) ∈ m_traversal_paths_with_witness M q RepSets m›
        unfolding pps_alt_def
        by (metis (mono_tags, lifting) ‹q1 ∈ snd d› ‹q2 ∈ snd d› mem_Collect_eq) 
      then have "[] ∈ tps q2" and "q1 ∈ rd_targets (q2,[])"
        unfolding tps_alt_def[OF ‹q2 ∈ fst ` d_reachable_states_with_preambles M›] 
                  rd_targets_alt_def[OF ‹q2 ∈ fst ` d_reachable_states_with_preambles M›] 
                  preamble_pair_tests_alt 
        by force+

      then show "([] ∈ tps q1 ∧ [] ∈ tps q2 ∧ q1 ∈ rd_targets (q2,[]) ∧ q2 ∈ rd_targets (q1,[]))"
        using ‹[] ∈ tps q1› ‹q2 ∈ rd_targets (q1,[])› 
        by simp
    qed

    ultimately show "(∀ p1 p2 p3 . p=p1@p2@p3 ⟶ p2 ≠ [] ⟶ target q p1 ∈ fst d ⟶ target q (p1@p2) ∈ fst d ⟶ target q p1 ≠ target q (p1@p2) ⟶ (p1 ∈ tps q ∧ (p1@p2) ∈ tps q ∧ target q p1 ∈ rd_targets (q,(p1@p2)) ∧ target q (p1@p2) ∈ rd_targets (q,p1)))
            ∧ (∀ p1 p2 q' . p=p1@p2 ⟶ q' ∈ image fst states_with_preambles ⟶ target q p1 ∈ fst d ⟶ q' ∈ fst d ⟶ target q p1 ≠ q' ⟶ (p1 ∈ tps q ∧ [] ∈ tps q' ∧ target q p1 ∈ rd_targets (q',[]) ∧ q' ∈ rd_targets (q,p1)))
            ∧ (∀ q1 q2 . q1 ≠ q2 ⟶ q1 ∈ snd d ⟶ q2 ∈ snd d ⟶ ([] ∈ tps q1 ∧ [] ∈ tps q2 ∧ q1 ∈ rd_targets (q2,[]) ∧ q2 ∈ rd_targets (q1,[])))"
      by blast
  qed

  have "implies_completeness_for_repetition_sets (Test_Suite states_with_preambles tps rd_targets atcs) M m RepSets"
    unfolding implies_completeness_for_repetition_sets.simps
    using p1 p2 p3 p4 p5 p6 p7
    by force
  then show "implies_completeness (calculate_test_suite_for_repetition_sets M m RepSets) M m"
    unfolding ‹calculate_test_suite_for_repetition_sets M m RepSets = Test_Suite states_with_preambles tps rd_targets atcs›
              implies_completeness_def
    by blast


  show "is_finite_test_suite (calculate_test_suite_for_repetition_sets M m RepSets)"
  proof -
    have "finite states_with_preambles"
      unfolding states_with_preambles_def d_reachable_states_with_preambles_def 
      using fsm_states_finite[of M] by simp

    moreover have "⋀ q p. q ∈ fst ` states_with_preambles ⟹ finite (rd_targets (q, p))"
    proof -
      fix q p assume "q ∈ fst ` states_with_preambles"
      then have "q ∈ fst ` d_reachable_states_with_preambles M" unfolding states_with_preambles_def by assumption

      have *: "finite ((λ(q, p, y). ((q, p), y)) ` (prefix_pair_tests q (m_traversal_paths_with_witness M q RepSets m) ∪
             (⋃q∈fst ` d_reachable_states_with_preambles M.
                 ⋃mrsps∈{m_traversal_paths_with_witness M q RepSets m}.
                    preamble_prefix_tests q mrsps (fst ` d_reachable_states_with_preambles M)) ∪
             preamble_pair_tests
              (⋃(q, y)∈(λq. (q, m_traversal_paths_with_witness M q RepSets m)) `
                        fst ` d_reachable_states_with_preambles M.
                  (λ(p, rd, dr). dr) ` y)
              (fst ` (λ((q1, q2), A). ((q1, q2), A, Inr q1, Inr q2)) ` r_distinguishable_state_pairs_with_separators M)))"
      proof -
        have * : "⋀ a b c f . finite (f ` (a ∪ b ∪ c)) = (finite (f`a) ∧ finite (f`b) ∧ finite (f`c))"
          by (simp add: image_Un) 

        have "finite ((λ(q, p, y). ((q, p), y)) ` (prefix_pair_tests q (m_traversal_paths_with_witness M q RepSets m)))"
        proof -
          have "prefix_pair_tests q (m_traversal_paths_with_witness M q RepSets m) ⊆ 
                    (⋃ (p, rd, dr)∈m_traversal_paths_with_witness M q RepSets m . ⋃ (p1, p2) ∈ set (prefix_pairs p) .{(q, p1, target q p2), (q, p2, target q p1)})"
            unfolding prefix_pair_tests.simps by blast
          moreover have "finite (⋃ (p, rd, dr)∈m_traversal_paths_with_witness M q RepSets m . ⋃ (p1, p2) ∈ set (prefix_pairs p) .{(q, p1, target q p2), (q, p2, target q p1)})"
          proof -
            have "finite (m_traversal_paths_with_witness M q RepSets m)"
              using m_traversal_paths_with_witness_finite[of M q "RepSets" m] by assumption
            moreover have "⋀ p rd dr . finite (⋃ (p1, p2) ∈ set (prefix_pairs p) .{(q, p1, target q p2), (q, p2, target q p1)})"
              by auto
            ultimately show ?thesis by force
          qed
          ultimately show ?thesis using infinite_super by blast
        qed

        moreover have "finite ((λ(q, p, y). ((q, p), y)) ` (⋃q∈fst ` d_reachable_states_with_preambles M.
                 ⋃mrsps∈{m_traversal_paths_with_witness M q RepSets m}.
                    preamble_prefix_tests q mrsps (fst ` d_reachable_states_with_preambles M)))"
        proof -
          have "finite (fst ` d_reachable_states_with_preambles M)" using ‹finite states_with_preambles› unfolding states_with_preambles_def by auto
          moreover have "⋀ q . q∈fst ` d_reachable_states_with_preambles M ⟹ finite (⋃mrsps∈{m_traversal_paths_with_witness M q RepSets m}. preamble_prefix_tests q mrsps (fst ` d_reachable_states_with_preambles M))"
          proof -
            fix q assume "q∈fst ` d_reachable_states_with_preambles M"

            have "finite {m_traversal_paths_with_witness M q RepSets m}" by simp
            moreover have "⋀ mrsps . mrsps∈{m_traversal_paths_with_witness M q RepSets m} ⟹ finite (preamble_prefix_tests q mrsps (fst ` d_reachable_states_with_preambles M))"
            proof -
              fix mrsps assume "mrsps∈{m_traversal_paths_with_witness M q RepSets m}"
              then have *: "mrsps = m_traversal_paths_with_witness M q RepSets m" by simp


              have "preamble_prefix_tests q mrsps (fst ` d_reachable_states_with_preambles M) 
                      ⊆ (⋃ (p,rd,dr) ∈ m_traversal_paths_with_witness M q RepSets m . ⋃ q2 ∈ (fst ` d_reachable_states_with_preambles M) . (⋃ p1 ∈ set (prefixes p) . {(q,p1,q2), (q2,[],(target q p1))}))"              
                unfolding preamble_prefix_tests_def * prefixes_set by blast
              moreover have "finite (⋃ (p,rd,dr) ∈ m_traversal_paths_with_witness M q RepSets m . ⋃ q2 ∈ (fst ` d_reachable_states_with_preambles M) . (⋃ p1 ∈ set (prefixes p) . {(q,p1,q2), (q2,[],(target q p1))}))"
              proof -
                have "finite (m_traversal_paths_with_witness M q RepSets m)"
                  using m_traversal_paths_with_witness_finite by metis
                moreover have "⋀ p rd dr . (p,rd,dr) ∈ m_traversal_paths_with_witness M q RepSets m ⟹ finite (⋃ q2 ∈ (fst ` d_reachable_states_with_preambles M) . (⋃ p1 ∈ set (prefixes p) . {(q,p1,q2), (q2,[],(target q p1))}))"
                  using ‹finite (fst ` d_reachable_states_with_preambles M)› by blast
                ultimately show ?thesis by force
              qed
              ultimately show "finite (preamble_prefix_tests q mrsps (fst ` d_reachable_states_with_preambles M))" using infinite_super by blast
            qed
            ultimately show "finite (⋃mrsps∈{m_traversal_paths_with_witness M q RepSets m}. preamble_prefix_tests q mrsps (fst ` d_reachable_states_with_preambles M))" by force
          qed
          ultimately show ?thesis by blast
        qed

        moreover have "finite ((λ(q, p, y). ((q, p), y)) ` (preamble_pair_tests
              (⋃(q, y)∈(λq. (q, m_traversal_paths_with_witness M q RepSets m)) `
                        fst ` d_reachable_states_with_preambles M.
                  (λ(p, rd, dr). dr) ` y)
              (fst ` (λ((q1, q2), A). ((q1, q2), A, Inr q1, Inr q2)) ` r_distinguishable_state_pairs_with_separators M)))"
        proof -

          have "finite (⋃(q, y)∈(λq. (q, m_traversal_paths_with_witness M q RepSets m)) `
                        fst ` d_reachable_states_with_preambles M.
                  (λ(p, rd, dr). dr) ` y)"
          proof -

            have *: "(⋃(q, y)∈(λq. (q, m_traversal_paths_with_witness M q RepSets m)) `
                        fst ` d_reachable_states_with_preambles M.
                  (λ(p, rd, dr). dr) ` y) =
                  (⋃ q ∈ fst ` d_reachable_states_with_preambles M . ⋃ (p, rd, dr) ∈ m_traversal_paths_with_witness M q RepSets m . {dr})"
              by force

            have "finite (⋃ q ∈ fst ` d_reachable_states_with_preambles M . ⋃ (p, rd, dr) ∈ m_traversal_paths_with_witness M q RepSets m . {dr})"
            proof -
              have "finite (fst ` d_reachable_states_with_preambles M)"
                using ‹finite states_with_preambles› unfolding states_with_preambles_def by auto

              moreover have "⋀q . q ∈ fst ` d_reachable_states_with_preambles M ⟹ finite (⋃ (p, rd, dr) ∈ m_traversal_paths_with_witness M q RepSets m . {dr})"
              proof -
                fix q assume "q ∈ fst ` d_reachable_states_with_preambles M"

                have "finite (m_traversal_paths_with_witness M q RepSets m)"
                  using  m_traversal_paths_with_witness_finite by metis 
                moreover have "⋀ p rd dr . (p, rd, dr) ∈ m_traversal_paths_with_witness M q RepSets m ⟹ finite {dr}"
                  by simp
                ultimately show "finite (⋃ (p, rd, dr) ∈ m_traversal_paths_with_witness M q RepSets m . {dr})"
                  by force
              qed
              ultimately show ?thesis by blast
            qed
            then show ?thesis unfolding * by assumption
          qed
          moreover have "finite (fst ` (λ((q1, q2), A). ((q1, q2), A, Inr q1, Inr q2)) ` r_distinguishable_state_pairs_with_separators M)"
          proof - 
            have "(fst ` (λ((q1, q2), A). ((q1, q2), A, Inr q1, Inr q2)) ` r_distinguishable_state_pairs_with_separators M) ⊆ states M × states M"
              unfolding r_distinguishable_state_pairs_with_separators_def by auto
            moreover have "finite (states M × states M)"
              using fsm_states_finite by auto
            ultimately show ?thesis using infinite_super by blast
          qed
          ultimately show ?thesis
            unfolding preamble_pair_tests.simps by blast
        qed

        ultimately show ?thesis 
          unfolding * by blast
          
      qed

      show "finite (rd_targets (q, p))"
        unfolding rd_targets_alt_def[OF ‹q ∈ fst ` d_reachable_states_with_preambles M›] 
        using finite_snd_helper[of _ q p, OF *] by assumption
    qed

    
    moreover have "⋀ q q'. finite (atcs (q, q'))"
    proof -
      fix q q' 
      show "finite (atcs (q,q'))" proof (cases "set_as_map ((λ((q1, q2), A). ((q1, q2), A, Inr q1:: ('a × 'a) + 'a, Inr q2 :: ('a × 'a) + 'a)) ` r_distinguishable_state_pairs_with_separators M) (q, q')")
        case None
        then have "atcs (q, q') = {}" unfolding atcs_def by auto
        then show ?thesis by auto
      next
        case (Some a)
        then have "atcs (q, q') = a" unfolding atcs_def by auto
        then have *: "atcs (q, q') = {z. ((q, q'), z) ∈ (λ((q1, q2), A). ((q1, q2), A, Inr q1:: ('a × 'a) + 'a, Inr q2:: ('a × 'a) + 'a)) ` r_distinguishable_state_pairs_with_separators M}" using Some unfolding set_as_map_def
          by (metis (no_types, lifting) option.distinct(1) option.inject) 


        have "finite (r_distinguishable_state_pairs_with_separators M)"
        proof -
          have "r_distinguishable_state_pairs_with_separators M ⊆ (⋃ q1 ∈ states M . ⋃ q2 ∈ states M . {((q1,q2), the (state_separator_from_s_states M q1 q2)), ((q1,q2), the (state_separator_from_s_states M q2 q1))})"
          proof 
            fix x assume "x ∈ r_distinguishable_state_pairs_with_separators M"
            then obtain q1 q2 Sep where "x = ((q1,q2),Sep)"
                                    and "q1 ∈ states M"
                                    and "q2 ∈ states M"
                                    and "(q1 < q2 ∧ state_separator_from_s_states M q1 q2 = Some Sep) ∨ (q2 < q1 ∧ state_separator_from_s_states M q2 q1 = Some Sep)"
              unfolding r_distinguishable_state_pairs_with_separators_def by blast
            then consider "state_separator_from_s_states M q1 q2 = Some Sep" | "state_separator_from_s_states M q2 q1 = Some Sep" by blast

            then show "x ∈ (⋃ q1 ∈ states M . ⋃ q2 ∈ states M . {((q1,q2), the (state_separator_from_s_states M q1 q2)), ((q1,q2), the (state_separator_from_s_states M q2 q1))})"
              using ‹q1 ∈ states M› ‹q2 ∈ states M› unfolding ‹x = ((q1,q2),Sep)› by (cases; force)
          qed

          moreover have "finite (⋃ q1 ∈ states M . ⋃ q2 ∈ states M . {((q1,q2), the (state_separator_from_s_states M q1 q2)), ((q1,q2), the (state_separator_from_s_states M q2 q1))})"
            using fsm_states_finite[of M] by force

          ultimately show ?thesis using infinite_super by blast
        qed
        then show ?thesis unfolding * by (simp add: finite_snd_helper)
      qed
    qed


    ultimately show ?thesis 
      unfolding ‹calculate_test_suite_for_repetition_sets M m  RepSets = Test_Suite states_with_preambles tps rd_targets atcs›
                is_finite_test_suite.simps 
      by blast
  qed
qed






subsection ‹Two Complete Example Implementations›

subsubsection ‹Naive Repetition Set Strategy›

definition calculate_test_suite_naive :: "('a::linorder,'b::linorder,'c) fsm ⇒ nat ⇒ ('a,'b,'c, ('a × 'a) + 'a) test_suite" where
  "calculate_test_suite_naive M m = calculate_test_suite_for_repetition_sets M m (maximal_repetition_sets_from_separators_list_naive M)" 

definition calculate_test_suite_naive_as_io_sequences :: "('a::linorder,'b::linorder,'c) fsm ⇒ nat ⇒ ('b × 'c) list set" where
  "calculate_test_suite_naive_as_io_sequences M m = test_suite_to_io_maximal M (calculate_test_suite_naive M m)"


lemma calculate_test_suite_naive_completeness :
  fixes M :: "('a::linorder,'b::linorder,'c) fsm"
  assumes "observable M" 
  and     "observable M'"
  and     "inputs M' = inputs M"
  and     "inputs M ≠ {}"
  and     "completely_specified M"
  and     "completely_specified M'"
  and     "size M' ≤ m"
shows     "(L M' ⊆ L M) ⟷ passes_test_suite M (calculate_test_suite_naive M m) M'"
and       "(L M' ⊆ L M) ⟷ pass_io_set_maximal M' (calculate_test_suite_naive_as_io_sequences M m)"
proof -

  have  "⋀q. q ∈ FSM.states M ⟹ ∃d∈set (maximal_repetition_sets_from_separators_list_naive M). q ∈ fst d"
    unfolding maximal_repetition_sets_from_separators_list_naive_def Let_def
    by (metis (mono_tags, lifting) list.set_map maximal_pairwise_r_distinguishable_state_sets_from_separators_code maximal_repetition_sets_from_separators_code maximal_repetition_sets_from_separators_cover)
  moreover have "⋀d. d ∈ set (maximal_repetition_sets_from_separators_list_naive M) ⟹ fst d ⊆ states M ∧ (snd d = fst d ∩ fst ` d_reachable_states_with_preambles M)" 
            and "⋀ d q1 q2. d ∈ set (maximal_repetition_sets_from_separators_list_naive M) ⟹ q1∈fst d ⟹ q2∈fst d ⟹ q1 ≠ q2 ⟹ (q1, q2) ∈ fst ` r_distinguishable_state_pairs_with_separators M"
  proof 
    fix d assume "d ∈ set (maximal_repetition_sets_from_separators_list_naive M)"
    then have "d ∈ maximal_repetition_sets_from_separators M"
      by (simp add: maximal_repetition_sets_from_separators_code_alt)
      

    then show "fst d ⊆ states M" and "(snd d = fst d ∩ fst ` d_reachable_states_with_preambles M)" 
          and "⋀ q1 q2 . q1∈fst d ⟹ q2∈fst d ⟹ q1 ≠ q2 ⟹ (q1, q2) ∈ fst ` r_distinguishable_state_pairs_with_separators M"
      unfolding maximal_repetition_sets_from_separators_def 
                maximal_pairwise_r_distinguishable_state_sets_from_separators_def
                pairwise_r_distinguishable_state_sets_from_separators_def 
      by force+
  qed
  ultimately have "implies_completeness (calculate_test_suite_naive M m) M m"
             and  "is_finite_test_suite (calculate_test_suite_naive M m)"
    using calculate_test_suite_for_repetition_sets_sufficient_and_finite[OF ‹observable M› ‹completely_specified M› ‹inputs M ≠ {}›]
    unfolding calculate_test_suite_naive_def by force+

  then show "(L M' ⊆ L M) ⟷ passes_test_suite M (calculate_test_suite_naive M m) M'"
       and  "(L M' ⊆ L M) ⟷ pass_io_set_maximal M' (calculate_test_suite_naive_as_io_sequences M m)"
    using passes_test_suite_completeness[OF _ assms] 
          passes_test_suite_as_maximal_sequences_completeness[OF _ _ assms] 
    unfolding calculate_test_suite_naive_as_io_sequences_def
    by blast+
qed


definition calculate_test_suite_naive_as_io_sequences_with_assumption_check :: "('a::linorder,'b::linorder,'c) fsm ⇒ nat ⇒ String.literal + (('b × 'c) list set)" where
  "calculate_test_suite_naive_as_io_sequences_with_assumption_check M m = 
    (if inputs M ≠ {}
      then if observable M 
        then if completely_specified M
          then (Inr (test_suite_to_io_maximal M (calculate_test_suite_naive M m)))
          else (Inl (STR ''specification is not completely specified''))
        else (Inl (STR ''specification is not observable''))
      else (Inl (STR ''specification has no inputs'')))"

lemma calculate_test_suite_naive_as_io_sequences_with_assumption_check_completeness :
  fixes M :: "('a::linorder,'b::linorder,'c) fsm"
  assumes "observable M'"
  and     "inputs M' = inputs M"
  and     "completely_specified M'"
  and     "size M' ≤ m"
  and     "calculate_test_suite_naive_as_io_sequences_with_assumption_check M m = Inr ts"
shows  "(L M' ⊆ L M) ⟷ pass_io_set_maximal M' ts"
proof -

  have "inputs M ≠ {}"
  and  "observable M" 
  and  "completely_specified M"
    using ‹calculate_test_suite_naive_as_io_sequences_with_assumption_check M m = Inr ts›
    unfolding calculate_test_suite_naive_as_io_sequences_with_assumption_check_def 
    by (meson Inl_Inr_False)+ 
  then have "ts = (test_suite_to_io_maximal M (calculate_test_suite_naive M m))"
    using ‹calculate_test_suite_naive_as_io_sequences_with_assumption_check M m = Inr ts›
    unfolding calculate_test_suite_naive_as_io_sequences_with_assumption_check_def
    by (metis sum.inject(2)) 
  then show ?thesis 
    using calculate_test_suite_naive_completeness(2)[OF ‹observable M› assms(1,2) ‹inputs M ≠ {}› 
                                                        ‹completely_specified M› assms(3,4)] 
    unfolding calculate_test_suite_naive_as_io_sequences_def
    by simp
qed



subsubsection ‹Greedy Repetition Set Strategy›

definition calculate_test_suite_greedy :: "('a::linorder,'b::linorder,'c) fsm ⇒ nat ⇒ ('a,'b,'c, ('a × 'a) + 'a) test_suite" where
  "calculate_test_suite_greedy M m = calculate_test_suite_for_repetition_sets M m (maximal_repetition_sets_from_separators_list_greedy M)" 

definition calculate_test_suite_greedy_as_io_sequences :: "('a::linorder,'b::linorder,'c) fsm ⇒ nat ⇒ ('b × 'c) list set" where
  "calculate_test_suite_greedy_as_io_sequences M m = test_suite_to_io_maximal M (calculate_test_suite_greedy M m)"

lemma calculate_test_suite_greedy_completeness :
  fixes M :: "('a::linorder,'b::linorder,'c) fsm"
  assumes "observable M" 
  and     "observable M'"
  and     "inputs M' = inputs M"
  and     "inputs M ≠ {}"
  and     "completely_specified M"
  and     "completely_specified M'"
  and     "size M' ≤ m"
shows     "(L M' ⊆ L M) ⟷ passes_test_suite M (calculate_test_suite_greedy M m) M'"
and       "(L M' ⊆ L M) ⟷ pass_io_set_maximal M' (calculate_test_suite_greedy_as_io_sequences M m)"
proof -

  have  "⋀q. q ∈ FSM.states M ⟹ ∃d∈set (maximal_repetition_sets_from_separators_list_greedy M). q ∈ fst d"
    unfolding maximal_repetition_sets_from_separators_list_greedy_def Let_def
    using greedy_pairwise_r_distinguishable_state_sets_from_separators_cover[of _ M]
    by simp 

  moreover have "⋀d. d ∈ set (maximal_repetition_sets_from_separators_list_greedy M) ⟹ fst d ⊆ states M ∧ (snd d = fst d ∩ fst ` d_reachable_states_with_preambles M)" 
            and "⋀ d q1 q2. d ∈ set (maximal_repetition_sets_from_separators_list_greedy M) ⟹ q1∈fst d ⟹ q2∈fst d ⟹ q1 ≠ q2 ⟹ (q1, q2) ∈ fst ` r_distinguishable_state_pairs_with_separators M"
  proof 
    fix d assume "d ∈ set (maximal_repetition_sets_from_separators_list_greedy M)"
    then have "fst d ∈ set (greedy_pairwise_r_distinguishable_state_sets_from_separators M)"
         and  "(snd d = fst d ∩ fst ` d_reachable_states_with_preambles M)"
      unfolding maximal_repetition_sets_from_separators_list_greedy_def Let_def by force+

    then have "fst d ∈ pairwise_r_distinguishable_state_sets_from_separators M"
      using greedy_pairwise_r_distinguishable_state_sets_from_separators_soundness by blast
    then show "fst d ⊆ states M" and "(snd d = fst d ∩ fst ` d_reachable_states_with_preambles M)" 
          and "⋀ q1 q2 . q1∈fst d ⟹ q2∈fst d ⟹ q1 ≠ q2 ⟹ (q1, q2) ∈ fst ` r_distinguishable_state_pairs_with_separators M"
      using ‹(snd d = fst d ∩ fst ` d_reachable_states_with_preambles M)›
      unfolding pairwise_r_distinguishable_state_sets_from_separators_def
      by force+ 
  qed
  ultimately have "implies_completeness (calculate_test_suite_greedy M m) M m"
             and  "is_finite_test_suite (calculate_test_suite_greedy M m)"
    using calculate_test_suite_for_repetition_sets_sufficient_and_finite[OF ‹observable M› ‹completely_specified M› ‹inputs M ≠ {}›]
    unfolding calculate_test_suite_greedy_def by force+

  then show "(L M' ⊆ L M) ⟷ passes_test_suite M (calculate_test_suite_greedy M m) M'"
       and  "(L M' ⊆ L M) ⟷ pass_io_set_maximal M' (calculate_test_suite_greedy_as_io_sequences M m)"
    using passes_test_suite_completeness[OF _ assms] 
          passes_test_suite_as_maximal_sequences_completeness[OF _ _ assms] 
    unfolding calculate_test_suite_greedy_as_io_sequences_def
    by blast+
qed


definition calculate_test_suite_greedy_as_io_sequences_with_assumption_check :: "('a::linorder,'b::linorder,'c) fsm ⇒ nat ⇒ String.literal + (('b × 'c) list set)" where
  "calculate_test_suite_greedy_as_io_sequences_with_assumption_check M m = 
    (if inputs M ≠ {}
      then if observable M 
        then if completely_specified M
          then (Inr (test_suite_to_io_maximal M (calculate_test_suite_greedy M m)))
          else (Inl (STR ''specification is not completely specified''))
        else (Inl (STR ''specification is not observable''))
      else (Inl (STR ''specification has no inputs'')))"

lemma calculate_test_suite_greedy_as_io_sequences_with_assumption_check_completeness :
  fixes M :: "('a::linorder,'b::linorder,'c) fsm"
  assumes "observable M'"
  and     "inputs M' = inputs M"
  and     "completely_specified M'"
  and     "size M' ≤ m"
  and     "calculate_test_suite_greedy_as_io_sequences_with_assumption_check M m = Inr ts"
shows  "(L M' ⊆ L M) ⟷ pass_io_set_maximal M' ts"
proof -

  have "inputs M ≠ {}"
  and  "observable M" 
  and  "completely_specified M"
    using ‹calculate_test_suite_greedy_as_io_sequences_with_assumption_check M m = Inr ts›
    unfolding calculate_test_suite_greedy_as_io_sequences_with_assumption_check_def 
    by (meson Inl_Inr_False)+ 
  then have "ts = (test_suite_to_io_maximal M (calculate_test_suite_greedy M m))"
    using ‹calculate_test_suite_greedy_as_io_sequences_with_assumption_check M m = Inr ts›
    unfolding calculate_test_suite_greedy_as_io_sequences_with_assumption_check_def
    by (metis sum.inject(2)) 
  then show ?thesis 
    using calculate_test_suite_greedy_completeness(2)[OF ‹observable M› assms(1,2) ‹inputs M ≠ {}› 
                                                        ‹completely_specified M› assms(3,4)] 
    unfolding calculate_test_suite_greedy_as_io_sequences_def
    by simp
qed

end