thys3/ClosedFormsBounds.thy
author Christian Urban <christian.urban@kcl.ac.uk>
Thu, 28 Apr 2022 15:56:22 +0100
changeset 495 f9cdc295ccf7
child 558 671a83abccf3
permissions -rw-r--r--
a fresh directory with cleaned up code


theory ClosedFormsBounds
  imports "GeneralRegexBound" "ClosedForms"
begin
lemma alts_ders_lambda_shape_ders:
  shows "\<forall>r \<in> set (map (\<lambda>r. rders_simp r ( s)) rs ). \<exists>r1 \<in> set rs. r = rders_simp r1 s"
  by (simp add: image_iff)

lemma rlist_bound:
  assumes "\<forall>r \<in> set rs. rsize r \<le> N"
  shows "rsizes rs \<le> N * (length rs)"
  using assms
  apply(induct rs)
  apply simp
  by simp

lemma alts_closed_form_bounded: 
  assumes "\<forall>r \<in> set rs. \<forall>s. rsize (rders_simp r s) \<le> N"
  shows "rsize (rders_simp (RALTS rs) s) \<le> max (Suc (N * (length rs))) (rsize (RALTS rs))"
proof (cases s)
  case Nil
  then show "rsize (rders_simp (RALTS rs) s) \<le> max (Suc (N * length rs)) (rsize (RALTS rs))"
    by simp
next
  case (Cons a s)
  
  from assms have "\<forall>r \<in> set (map (\<lambda>r. rders_simp r (a # s)) rs ). rsize r \<le> N"
    by (metis alts_ders_lambda_shape_ders)
  then have a: "rsizes (map (\<lambda>r. rders_simp r (a # s)) rs ) \<le> N *  (length rs)"
    by (metis length_map rlist_bound) 
     
  have "rsize (rders_simp (RALTS rs) (a # s)) 
          = rsize (rsimp (RALTS (map (\<lambda>r. rders_simp r (a # s)) rs)))"
    by (metis alts_closed_form_variant list.distinct(1)) 
  also have "... \<le> rsize (RALTS (map (\<lambda>r. rders_simp r (a # s)) rs))"
    using rsimp_mono by blast
  also have "... = Suc (rsizes (map (\<lambda>r. rders_simp r (a # s)) rs))"
    by simp
  also have "... \<le> Suc (N * (length rs))"
    using a by blast
  finally have "rsize (rders_simp (RALTS rs) (a # s)) \<le> max (Suc (N * length rs)) (rsize (RALTS rs))" 
    by auto
  then show ?thesis using local.Cons by simp 
qed

lemma alts_simp_ineq_unfold:
  shows "rsize (rsimp (RALTS rs)) \<le> Suc (rsizes (rdistinct (rflts (map rsimp rs)) {}))"
  using rsimp_aalts_smaller by auto


lemma rdistinct_mono_list:
  shows "rsizes (rdistinct (x5 @ rs) rset) \<le> rsizes x5 + rsizes (rdistinct  rs ((set x5 ) \<union> rset))"
  apply(induct x5 arbitrary: rs rset)
   apply simp
  apply(case_tac "a \<in> rset")
   apply simp
   apply (simp add: add.assoc insert_absorb trans_le_add2)
  apply simp
  by (metis Un_insert_right)


lemma flts_size_reduction_alts:
  assumes a: "\<And>noalts_set alts_set corr_set.
           (\<forall>r\<in>noalts_set. \<forall>xs. r \<noteq> RALTS xs) \<and>
           (\<forall>a\<in>alts_set. \<exists>xs. a = RALTS xs \<and> set xs \<subseteq> corr_set) \<Longrightarrow>
           Suc (rsizes (rdistinct (rflts rs) (noalts_set \<union> corr_set)))
           \<le> Suc (rsizes (rdistinct rs (insert RZERO (noalts_set \<union> alts_set))))"
 and b: "\<forall>r\<in>noalts_set. \<forall>xs. r \<noteq> RALTS xs"
 and c: "\<forall>a\<in>alts_set. \<exists>xs. a = RALTS xs \<and> set xs \<subseteq> corr_set"
 and d: "a = RALTS x5"
 shows "rsizes (rdistinct (rflts (a # rs)) (noalts_set \<union> corr_set))
           \<le> rsizes (rdistinct (a # rs) (insert RZERO (noalts_set \<union> alts_set)))"
  
  apply(case_tac "a \<in> alts_set")
  using a b c d
   apply simp
   apply(subgoal_tac "set x5 \<subseteq> corr_set")
  apply(subst rdistinct_concat)
  apply auto[1]
    apply presburger
   apply fastforce
  using a b c d
  apply (subgoal_tac "a \<notin> noalts_set")
  prefer 2
  apply blast
  apply simp
  apply(subgoal_tac "rsizes (rdistinct (x5 @ rflts rs) (noalts_set \<union> corr_set)) 
                   \<le> rsizes x5 + rsizes (rdistinct (rflts rs) ((set x5) \<union> (noalts_set \<union> corr_set)))")
  prefer 2
  using rdistinct_mono_list apply presburger
  apply(subgoal_tac "insert (RALTS x5) (noalts_set \<union> alts_set) = noalts_set \<union> (insert (RALTS x5) alts_set)")
   apply(simp only:)
  apply(subgoal_tac "rsizes x5 + rsizes (rdistinct (rflts rs) (noalts_set \<union> (corr_set \<union> (set x5)))) \<le>
           rsizes x5 + rsizes (rdistinct rs (insert RZERO (noalts_set \<union> insert (RALTS x5) alts_set)))")
  
  apply (simp add: Un_left_commute inf_sup_aci(5))
   apply(subgoal_tac "rsizes (rdistinct (rflts rs) (noalts_set \<union> (corr_set \<union> set x5))) \<le> 
                    rsizes (rdistinct rs (insert RZERO (noalts_set \<union> insert (RALTS x5) alts_set)))")
    apply linarith
   apply(subgoal_tac "\<forall>r \<in> insert (RALTS x5) alts_set. \<exists>xs1.( r = RALTS xs1 \<and> set xs1 \<subseteq> corr_set \<union> set x5)")
    apply presburger
   apply (meson insert_iff sup.cobounded2 sup.coboundedI1)
  by blast


lemma flts_vs_nflts1:
  assumes "\<forall>r \<in> noalts_set. \<forall>xs. r \<noteq> RALTS xs"
  and "\<forall>a \<in> alts_set. (\<exists>xs. a = RALTS xs \<and> set xs \<subseteq> corr_set)" 
  shows "rsizes (rdistinct (rflts rs) (noalts_set \<union> corr_set))
         \<le> rsizes (rdistinct rs (insert RZERO (noalts_set \<union> alts_set)))"
  using assms
    apply(induct rs arbitrary: noalts_set alts_set corr_set)
   apply simp
  apply(case_tac a)
       apply(case_tac "RZERO \<in> noalts_set")
        apply simp
       apply(subgoal_tac "RZERO \<notin> alts_set")
        apply simp
       apply fastforce
      apply(case_tac "RONE \<in> noalts_set")
       apply simp
      apply(subgoal_tac "RONE \<notin> alts_set")
  prefer 2
  apply fastforce
      apply(case_tac "RONE \<in> corr_set")
       apply(subgoal_tac "rflts (a # rs) = RONE # rflts rs")
        apply(simp only:)
        apply(subgoal_tac "rdistinct (RONE # rflts rs) (noalts_set \<union> corr_set) = 
                           rdistinct (rflts rs) (noalts_set \<union> corr_set)")
         apply(simp only:)
  apply(subgoal_tac "rdistinct (RONE # rs) (insert RZERO (noalts_set \<union> alts_set)) =
                     RONE # (rdistinct rs (insert RONE (insert RZERO (noalts_set \<union> alts_set)))) ")
          apply(simp only:)
  apply(subgoal_tac "rdistinct (rflts rs) (noalts_set \<union> corr_set) = 
                     rdistinct (rflts rs) (insert RONE (noalts_set \<union> corr_set))")
  apply (simp only:)
  apply(subgoal_tac "insert RONE (noalts_set \<union> corr_set) = (insert RONE noalts_set) \<union> corr_set")
            apply(simp only:)
  apply(subgoal_tac "insert RONE (insert RZERO (noalts_set \<union> alts_set)) = 
                     insert RZERO ((insert RONE noalts_set) \<union> alts_set)")
             apply(simp only:)
  apply(subgoal_tac "rsizes (rdistinct rs (insert RZERO (insert RONE noalts_set \<union> alts_set)))
                   \<le>  rsizes (RONE # rdistinct rs (insert RZERO (insert RONE noalts_set \<union> alts_set)))")
  apply (smt (verit, best) dual_order.trans insert_iff rrexp.distinct(15))
  apply (metis (no_types, opaque_lifting)  le_add_same_cancel2 list.simps(9) sum_list.Cons zero_le)
            apply fastforce
           apply fastforce
  apply (metis Un_iff insert_absorb)
         apply (metis UnE insertE insert_is_Un rdistinct.simps(2) rrexp.distinct(1))
        apply (meson UnCI rdistinct.simps(2))
  using rflts.simps(4) apply presburger
      apply simp
      apply(subgoal_tac "insert RONE (noalts_set \<union> corr_set) = (insert RONE noalts_set) \<union> corr_set")
  apply(simp only:)
  apply (metis Un_insert_left insertE rrexp.distinct(15))
      apply fastforce
     apply(case_tac "a \<in> noalts_set")
      apply simp
  apply(subgoal_tac "a \<notin> alts_set")
      prefer 2
      apply blast
  apply(case_tac "a \<in> corr_set")
      apply(subgoal_tac "noalts_set \<union> corr_set = insert a ( noalts_set  \<union> corr_set)")
  prefer 2
  apply fastforce
      apply(simp only:)
      apply(subgoal_tac "rsizes (rdistinct (a # rs) (insert RZERO ((insert a noalts_set) \<union> alts_set))) \<le>
              rsizes (rdistinct (a # rs) (insert RZERO (noalts_set \<union> alts_set)))")

       apply(subgoal_tac  "rsizes (rdistinct (rflts (a # rs)) ((insert a noalts_set) \<union> corr_set)) \<le>
              rsizes (rdistinct (a # rs) (insert RZERO ((insert a noalts_set) \<union> alts_set)))")
  apply fastforce
       apply simp
  apply(subgoal_tac "(insert a (noalts_set \<union> alts_set)) = (insert a noalts_set) \<union> alts_set")
        apply(simp only:)
        apply(subgoal_tac "noalts_set \<union> corr_set = (insert a noalts_set) \<union> corr_set")
  apply(simp only:)
  apply (metis insertE rrexp.distinct(21))
        apply blast
  
  apply fastforce
  apply force
     apply simp
     apply (metis Un_insert_left insert_iff rrexp.distinct(21))
    apply(case_tac "a \<in> noalts_set")
     apply simp
  apply(subgoal_tac "a \<notin> alts_set")
      prefer 2
      apply blast
  apply(case_tac "a \<in> corr_set")
      apply(subgoal_tac "noalts_set \<union> corr_set = insert a ( noalts_set  \<union> corr_set)")
  prefer 2
  apply fastforce
      apply(simp only:)
      apply(subgoal_tac "rsizes (rdistinct (a # rs) (insert RZERO ((insert a noalts_set) \<union> alts_set))) \<le>
             rsizes (rdistinct (a # rs) (insert RZERO (noalts_set \<union> alts_set)))")

       apply(subgoal_tac "rsizes (rdistinct (rflts (a # rs)) ((insert a noalts_set) \<union> corr_set)) \<le>
          rsizes (rdistinct (a # rs) (insert RZERO ((insert a noalts_set) \<union> alts_set)))")
  apply fastforce
       apply simp
  apply(subgoal_tac "(insert a (noalts_set \<union> alts_set)) = (insert a noalts_set) \<union> alts_set")
        apply(simp only:)
        apply(subgoal_tac "noalts_set \<union> corr_set = (insert a noalts_set) \<union> corr_set")
  apply(simp only:)


  apply (metis insertE rrexp.distinct(25))
  apply blast
  apply fastforce
  apply force
     apply simp
  
    apply (metis Un_insert_left insertE rrexp.distinct(25))

  using Suc_le_mono flts_size_reduction_alts apply presburger
     apply(case_tac "a \<in> noalts_set")
      apply simp
  apply(subgoal_tac "a \<notin> alts_set")
      prefer 2
      apply blast
  apply(case_tac "a \<in> corr_set")
      apply(subgoal_tac "noalts_set \<union> corr_set = insert a ( noalts_set  \<union> corr_set)")
  prefer 2
  apply fastforce
      apply(simp only:)
      apply(subgoal_tac "rsizes (rdistinct (a # rs) (insert RZERO ((insert a noalts_set) \<union> alts_set))) \<le>
               rsizes (rdistinct (a # rs) (insert RZERO (noalts_set \<union> alts_set)))")

       apply(subgoal_tac "rsizes (rdistinct (rflts (a # rs)) ((insert a noalts_set) \<union> corr_set)) \<le>
          rsizes (rdistinct (a # rs) (insert RZERO ((insert a noalts_set) \<union> alts_set)))")
  apply fastforce
       apply simp
  apply(subgoal_tac "(insert a (noalts_set \<union> alts_set)) = (insert a noalts_set) \<union> alts_set")
        apply(simp only:)
        apply(subgoal_tac "noalts_set \<union> corr_set = (insert a noalts_set) \<union> corr_set")
  apply(simp only:)
  apply (metis insertE rrexp.distinct(29))

        apply blast
  
  apply fastforce
  apply force
     apply simp
  apply (metis Un_insert_left insert_iff rrexp.distinct(29))
  done


lemma flts_vs_nflts:
  assumes "\<forall>r \<in> noalts_set. \<forall>xs. r \<noteq> RALTS xs"
  and "\<forall>a \<in> alts_set. (\<exists>xs. a = RALTS xs \<and> set xs \<subseteq> corr_set)"
  shows "rsizes (rdistinct (rflts rs) (noalts_set \<union> corr_set))
         \<le> rsizes (rdistinct rs (insert RZERO (noalts_set \<union> alts_set)))"
  by (simp add: assms flts_vs_nflts1)

lemma distinct_simp_ineq_general:
  assumes "rsimp ` no_simp = has_simp" "finite no_simp"
  shows "rsizes (rdistinct (map rsimp rs) has_simp) \<le> rsizes (rdistinct rs no_simp)"
  using assms
  apply(induct rs no_simp arbitrary: has_simp rule: rdistinct.induct)
  apply simp
  apply(auto)
  using add_le_mono rsimp_mono by presburger

lemma larger_acc_smaller_distinct_res0:
  assumes "ss \<subseteq> SS"
  shows "rsizes (rdistinct rs SS) \<le> rsizes (rdistinct rs ss)"
  using assms
  apply(induct rs arbitrary: ss SS)
   apply simp
  by (metis distinct_early_app1 rdistinct_smaller)

lemma without_flts_ineq:
  shows "rsizes (rdistinct (rflts rs) {}) \<le> rsizes (rdistinct rs {})"
proof -
  have "rsizes (rdistinct (rflts rs) {}) \<le>  rsizes (rdistinct rs (insert RZERO {}))"
    by (metis empty_iff flts_vs_nflts sup_bot_left)
  also have "... \<le>  rsizes (rdistinct rs {})" 
    by (simp add: larger_acc_smaller_distinct_res0)
  finally show ?thesis
    by blast
qed


lemma distinct_simp_ineq:
  shows "rsizes (rdistinct (map rsimp rs) {}) \<le> rsizes (rdistinct rs {})"
  using distinct_simp_ineq_general by blast


lemma alts_simp_control:
  shows "rsize (rsimp (RALTS rs)) \<le> Suc (rsizes (rdistinct rs {}))"
proof -
  have "rsize (rsimp (RALTS rs)) \<le> Suc (rsizes (rdistinct (rflts (map rsimp rs)) {}))"
     using alts_simp_ineq_unfold by auto
   moreover have "\<dots> \<le> Suc (rsizes (rdistinct (map rsimp rs) {}))"
    using without_flts_ineq by blast
  ultimately show "rsize (rsimp (RALTS rs)) \<le> Suc (rsizes (rdistinct rs {}))"
    by (meson Suc_le_mono distinct_simp_ineq le_trans)
qed


lemma larger_acc_smaller_distinct_res:
  shows "rsizes (rdistinct rs (insert a ss)) \<le> rsizes (rdistinct rs ss)"
  by (simp add: larger_acc_smaller_distinct_res0 subset_insertI)

lemma triangle_inequality_distinct:
  shows "rsizes (rdistinct (a # rs) ss) \<le> rsize a + rsizes (rdistinct rs ss)"
  apply(case_tac "a \<in> ss")
   apply simp
  by (simp add: larger_acc_smaller_distinct_res)


lemma distinct_list_size_len_bounded:
  assumes "\<forall>r \<in> set rs. rsize r \<le> N" "length rs \<le> lrs"
  shows "rsizes rs \<le> lrs * N "
  using assms
  by (metis rlist_bound dual_order.trans mult.commute mult_le_mono1)



lemma rdistinct_same_set:
  shows "r \<in> set rs \<longleftrightarrow> r \<in> set (rdistinct rs {})"
  apply(induct rs)
   apply simp
  by (metis rdistinct_set_equality)

(* distinct_list_rexp_up_to_certain_size_bouded_by_set_enumerating_up_to_that_size *)
lemma distinct_list_rexp_upto:
  assumes "\<forall>r\<in> set rs. (rsize r) \<le> N"
  shows "rsizes (rdistinct rs {}) \<le> (card (sizeNregex N)) * N"
  
  apply(subgoal_tac "distinct (rdistinct rs {})")
  prefer 2
  using rdistinct_does_the_job apply blast
  apply(subgoal_tac "length (rdistinct rs {}) \<le> card (sizeNregex N)")
  apply(rule distinct_list_size_len_bounded)
  using assms
  apply (meson rdistinct_same_set)
   apply blast
  apply(subgoal_tac "\<forall>r \<in> set (rdistinct rs {}). rsize r \<le> N")
   prefer 2
  using assms
   apply (meson rdistinct_same_set)
  apply(subgoal_tac "length (rdistinct rs {}) = card (set (rdistinct rs {}))")
   prefer 2
  apply (simp add: distinct_card)
  apply(simp)
  by (metis card_mono finite_size_n mem_Collect_eq sizeNregex_def subsetI)


lemma star_control_bounded:
  assumes "\<forall>s. rsize (rders_simp r s) \<le> N"
  shows "rsizes (rdistinct (map (\<lambda>s1. RSEQ (rders_simp r s1) (RSTAR r)) (star_updates s r [[c]])) {}) 
     \<le> (card (sizeNregex (Suc (N + rsize (RSTAR r))))) * (Suc (N + rsize (RSTAR r)))"
  by (smt (verit) add_Suc_shift add_mono_thms_linordered_semiring(3) assms distinct_list_rexp_upto image_iff list.set_map plus_nat.simps(2) rsize.simps(5))


lemma star_closed_form_bounded:
  assumes "\<forall>s. rsize (rders_simp r s) \<le> N"
  shows "rsize (rders_simp (RSTAR r) s) \<le> 
           max ((Suc (card (sizeNregex (Suc (N + rsize (RSTAR r))))) * (Suc (N + rsize (RSTAR r))))) (rsize (RSTAR r))"
proof(cases s)
  case Nil
  then show "rsize (rders_simp (RSTAR r) s)
    \<le> max (Suc (card (sizeNregex (Suc (N + rsize (RSTAR r))))) * Suc (N + rsize (RSTAR r))) (rsize (RSTAR r))" 
    by simp
next
  case (Cons a list)
  then have "rsize (rders_simp (RSTAR r) s) = 
    rsize (rsimp (RALTS ((map (\<lambda>s1. RSEQ (rders_simp r s1) (RSTAR r)) (star_updates list r [[a]])))))"
    using star_closed_form by fastforce
  also have "... \<le> Suc (rsizes (rdistinct (map (\<lambda>s1. RSEQ (rders_simp r s1) (RSTAR r)) (star_updates list r [[a]])) {}))"
    using alts_simp_control by blast 
  also have "... \<le> Suc (card (sizeNregex (Suc (N + rsize (RSTAR r))))) * (Suc (N + rsize (RSTAR r)))" 
    using star_control_bounded[OF assms] by (metis add_mono le_add1 mult_Suc plus_1_eq_Suc)
  also have "... \<le> max (Suc (card (sizeNregex (Suc (N + rsize (RSTAR r))))) * Suc (N + rsize (RSTAR r))) (rsize (RSTAR r))"
    by simp    
  finally show ?thesis by simp  
qed


lemma seq_estimate_bounded: 
  assumes "\<forall>s. rsize (rders_simp r1 s) \<le> N1" 
      and "\<forall>s. rsize (rders_simp r2 s) \<le> N2"
  shows
    "rsizes (rdistinct (RSEQ (rders_simp r1 s) r2 # map (rders_simp r2) (vsuf s r1)) {}) 
       \<le> (Suc (N1 + (rsize r2)) + (N2 * card (sizeNregex N2)))"
proof -
  have a: "rsizes (rdistinct (map (rders_simp r2) (vsuf s r1)) {}) \<le> N2 * card (sizeNregex N2)"
    by (metis assms(2) distinct_list_rexp_upto ex_map_conv mult.commute)

  have "rsizes (rdistinct (RSEQ (rders_simp r1 s) r2 # map (rders_simp r2) (vsuf s r1)) {}) \<le>
          rsize (RSEQ (rders_simp r1 s) r2) + rsizes (rdistinct (map (rders_simp r2) (vsuf s r1)) {})"
    using triangle_inequality_distinct by blast    
  also have "... \<le> rsize (RSEQ (rders_simp r1 s) r2) + N2 * card (sizeNregex N2)"
    by (simp add: a)
  also have "... \<le> Suc (N1 + (rsize r2) + N2 * card (sizeNregex N2))"
    by (simp add: assms(1))
  finally show ?thesis
    by force
qed    


lemma seq_closed_form_bounded2: 
  assumes "\<forall>s. rsize (rders_simp r1 s) \<le> N1"
  and     "\<forall>s. rsize (rders_simp r2 s) \<le> N2"
shows "rsize (rders_simp (RSEQ r1 r2) s) 
          \<le> max (2 + N1 + (rsize r2) + (N2 * card (sizeNregex N2))) (rsize (RSEQ r1 r2))"
proof(cases s)
  case Nil
  then show "rsize (rders_simp (RSEQ r1 r2) s)
     \<le> max (2 + N1 + (rsize r2) + (N2 * card (sizeNregex N2))) (rsize (RSEQ r1 r2))" 
    by simp
next
  case (Cons a list)
  then have "rsize (rders_simp (RSEQ r1 r2) s) = 
    rsize (rsimp (RALTS ((RSEQ (rders_simp r1 s) r2) # (map (rders_simp r2) (vsuf s r1)))))" 
    using seq_closed_form_variant by (metis list.distinct(1)) 
  also have "... \<le> Suc (rsizes (rdistinct (RSEQ (rders_simp r1 s) r2 # map (rders_simp r2) (vsuf s r1)) {}))"
    using alts_simp_control by blast
  also have "... \<le> 2 + N1 + (rsize r2) + (N2 * card (sizeNregex N2))"
  using seq_estimate_bounded[OF assms] by auto
  ultimately show "rsize (rders_simp (RSEQ r1 r2) s)
       \<le> max (2 + N1 + (rsize r2) + N2 * card (sizeNregex N2)) (rsize (RSEQ r1 r2))"
    by auto 
qed


lemma rders_simp_bounded: 
  shows "\<exists>N. \<forall>s. rsize (rders_simp r s) \<le> N"
  apply(induct r)
  apply(rule_tac x = "Suc 0 " in exI)
  using three_easy_cases0 apply force
  using three_easy_cases1 apply blast
  using three_easy_casesC apply blast
  apply(erule exE)+
  apply(rule exI)
  apply(rule allI)
  apply(rule seq_closed_form_bounded2)
  apply(assumption)
  apply(assumption)
  apply (metis alts_closed_form_bounded size_list_estimation')
  using star_closed_form_bounded by blast


unused_thms

end