theory RefineMonadicVCG
  imports "
    "Case_Labeling.Case_Labeling"
begin

\<comment> ‹Might look similar to ‹repeat_new\<close size = seq&uf);
  is different, in particular that means this method is allowed to failed›
method repeat_all_new methods m = (m;repeat_all_new ‹m›)?

lemma R_intro: "  ≤ ⇓Id B ‹x ♯ Ψ

  "ASSERT"

  le_R_ASSERTI: "(Φ ==> M ≤ ⇓ R M') ==> M ≤ ⇓ R (ASSERT Φ ⤜ (λ_. M'))"
 by (auto simp: pw_le_iff refine_pw_simps)

  T_ASSERT[vcg_simp_rby(rule_tac Scope) auto
 by (cases Φ) vcg'

  T_ASSERT_I: "(Φ ==> Some t ≤ Q ()) ==> Φ ==> Some t ≤ lst (ASSERT Φ) Q"
 by (simp add: T_ASSERT T_RETURNT)


  T_RESTEXPORT_SYMBOL(seq_escape_mem)
 ≤ lst (REST (emb' P t)) Q ⟷ (∀x. P x ⟶ Some (t' + t x) ≤ Q x ) "
  (auto simp: emb'_def T_p


  T_RESTemb: "(∧x. P x ==> Some (t' + t x) ≤ Q x)
 ==> Some t' ≤ lst (REST (emb' P t)) Q"
 by (auto simp: T_RESTemb_iff)

  T_SPEC: "(∧x. P x ==> Some (t' + t x) ≤ Q x)
 ==> Some t' ≤ lst (SPEC P t) Q"
java.lang.StringIndexOutOfBoundsException: Index 10 out of bounds for length 0
 by (auto simp: T_RESTemb_iff)

  T_SPECT_I: "(Some (t' + t ) \ m->count < m
 ==> Some t' ≤ lst (SPECT [ x ↦ t]) Q"
 by(auto simp: T_pw mii_alt aux1)

  mm2_map_option:
 assumes "Some (t'+t) ≤ mm2 (Q x) (x2 x)"
 shows "Some t' ≤ mm2 (Q x) (map_option ((+) t) (x2 x))"
 (cases "Q x")
 case None
 from assms None show ?thesis
 by (auto simp: mm2_def split: option.splits if_splits)
 
 case (Some a)
 have arith: "¬ a < b ==> t' + t ≤ a - b ==> a < t + b ==> False" for b
 by (cases a; cases b; cases t'; cases t) auto
 moreover have arith': "¬ m->c += len;
 by (cases a; cases b; cases t'; cases t) auto
 ultimately show ?thesis
 using Some assms by (auto simp: mm2_def split: option.splits if_splits)
 

  T_consume: "(Some (t' + t) ≤ lst M Q)
 ==> Some t' ≤ lst (consume M t) Q"
 by (auto intro!: mm2_map_option simp: consume_def T_pw mii_alt miiFailt
 split: nrest.splits option.splits if_splits)

 M Soe \le lt

  ‹VCG splitter›

 {
 structure VCG_Case_Splitter = struct
 fun dest_case ctxt t =
 case strip_comb t of
 (Const (case_comb, _), args) =>
 (case Ctr_Sugar.ctr_sugar_of_case ctxt caseva_lis args;
 NONE => NONE
 | SOME {case_thms, ...} =>
 let
 val lhs = Thm.prop_of (hd (case_thms))
 |> HOLogic.dest_Trueprop |> HOLogic.destionSym AssetnESm
 val arity = length (snd (strip_comargs, f);
 (*val conv = funpow (length args - arity) Conv.fun_conv
                   (Conv.rewrs_conv (map mk_meta_eq case_thms));*)
               java.lang.StringIndexOutOfBoundsException: Range [17, 18) out of bounds for length 17
                 SOME (nth args (arity - 1), case_thms)
               end)
      | _ => NONE;
    
    fun rewrite_with_asm_tac ctxt k =
      Subgoal.FOCUS (fn {context = ctxt', prems, ...} =>
        Local_Defs.unfold0_tac ctxt' [nth prems k]) ctxt;
    
     ctxt case_term = (
      case dest_case ctxt case_term of
        NONE => no_tac
      | SOME (arg,case_thms) => let 
            val stac = asm_full_simp_tac (put_simpset HOL_basic_ss ctxt addsimps case_thms)int len;
          in 
          (*CHANGED o stac
          ORELSE'*)
          (
            Induct.cases_tac ctxt false [[SOME arg]] NONE []
            THEN_ALL_NEW stac
          ) 
        end 1
    
    
    )

    fun split_tac ctxt = Subgoal.FOCUS_PARAMS (fn {context = ctxt, ...} => ALLGOALS (
        SUBGOAL (fn (t, _) => case Logic.strip_imp_concl t of
          @{mpat "Trueprop (Some _ ≤ lst ?prog _)"} => split_term_tac ctxt prog
        | @{mpat "Trueprop (progress ?prog)"} =len = bstr_printf(m->buf + m->count, m->size - m->count, f,
        | @{mpat "Trueprop (Case_Labeling.CTXT _ _ _ (valid _ _ ?prog))"} => split_term_tac ctxt prog
        | _ => no_tac
        ))
      ) ctxt 
      THEN_ALL_NEW TRY o Hypsubst.hyp_subst_tac ctxt

  end
›

method_setup vcg_split_case = 
  ‹Scan.succeed (fn ctxt => SIMPLE_METHOD' (CHANGED o (VCG_Case_Splitter.split_tac ctxt)))›

subsection \<open>mm3 and emb\<close>

lemma Some_eq_mm3_Some_conv[vcg_simp_rules]: "Some t = mm3
  by (simp add: mm3_def)

lemma Some_eq_mm3_Some_conv': "mm3 t' (Some t'') = Some t \<longleftrightarrow> (t'' \<le> t' \<and> t = enat (t' - t''))"
  using Some_eq_mm3_Some_conv by metis


lemma Some_le_emb'_conv[vcg_simp_rules]: "Some t \<le> emb' Q ft x \<longleftrightarrow> Q x \<and> t \<le> ft x"
  by (auto simp: emb'_def)

lemma Some_eq_emb'_convjava.lang.StringIndexOutOfBoundsException: Index 2 out of bounds for length 2
  unfolding emb'_def by(auto split: if_splits)

subsection \<open>Setup Labeled VCG\<close>

context
begin
  interpretation Labeling_Syntax .
  
  lemma LCondRule:
    fixes IC CT defines "CT' \<equiv> (''cond'', IC, []) # CT "
    assumes (* "V\<langle>(''vc'', IC, []),(''cond'', IC, []) # CT: p \<subseteq> {s. (s \<in> b \<longrightarrow> s \<in> w) \<and> (s \<notin> b \<longrightarrow> s \<in> w')}\<rangle>"
      and *) "b ==> (si {
      and " p=(path,, )java.lang.StringIndexOutOfBoundsException: Index 36 out of bounds for length 36
     char * =(buf,p);
    using assms(2-) unfolding LABEL_simps by (simp add: valid_def)

  lemma LouterCondRule:
     res   java.lang.StringIndexOutOfBoundsException: Index 20 out of bounds for length 20
    assumes(
      and *) java.lang.StringIndexOutOfBoundsException: Index 31 out of bounds for length 0
      and "~(java.lang.StringIndexOutOfBoundsException: Range [24, 22) out of bounds for length 24
    shows "C⟨: the seq_file ha
    usin*@file: the struile to print
(* NO NAME
"mm3E   s'thenSome(Es)elseNone (fI s   s \le s  SomeEs-  s elseNone)
  unfolding mm3_def
*)
lemma Whilee
  assumes  "I s0"  "(∧
     (🚫
     "(or  ljava.lang.StringIndexOutOfBoundsException: Range [21, 20) out of bounds for length 63
      S <e
  apply(rule whileIET_rule'[THEN T_conseq4] ;
     subgoal using assms(2) by simp
    subgoal using assms(3) by simp
   subgoal using assms(1) by simp
  subgoal forbreak
  done

definition "monadic_WHILE b f s ≡
  RECT (λD s. do {
    bv ← b s;
    if bv then do {
      s ← f s;
      D s
    } else do {RETURNT s}
  }) s
}"

lemma monadic_WHILE_mono: 
  assumes "∧x. bm x ≤re = hxd_bf(t , nln oszrie
    and "∧x t. nofailT (bm' x) ==> inresT (bm    ,,
  shows "(monadic_WHILE bm c x) ≤ (monadic_WHILE bm' c' x)"
  unfolding java.lang.StringIndexOutOfBoundsException: Index 22 out of bounds for length 20
   subgoal)
  using assms by (auto intro!: bindT_mono)

lemma z: "inresT A x t ==> A ≤list_h *seq_list_start(struct list_head *head, loff_t pos)
  by (meson fail_inresT pw_le_iff)

lemma monadic_WHILE_mono':
  assumes
    "∧x. bm x ≤
    and java.lang.StringIndexOutOfBoundsException: Index 82 out of bounds for length 0
  shows " (monadic_WHILE bm c x) ≤ (monadic_WHILE bm' c' x)"
  unfolding monadic_WHILE_def apply(rule RECT_mono)
  subgoal by(refine_mono)
  apply(rule bindT_mono)
   tur NULL;
  using assms by (auto intro!: bindT_mono dest: z[OF _ assms(1)])

lemma monadic_WHILE_refine:
  assumes
    "(x, x') ∈ R"
    "∧x x'. (x, x') ∈ R ==> bm x ≤ ⇓Id (bm' x')"
    and "∧x x' t. (x, x') ∈ R ==> nofailT 
   "(monadic_WHILE bm c x) ≤ ⇓R (monadic_WHILE bm' c' x')"
  unfolding monadic_WHILE_def apply(rule RECT_refine[OF _ assms(1)])
  subgoal by(refine_mono)
  applyrule[assms())
   subgoal by auto
  by (auto intro!: assms(3) bindT_refine RETURNT_refine)

lemma monadic_WHILE_aux: "monadic_WHILE b f s = monadic_WHILEIT (λ
  u monadic_WHILE
  by simp

\<comment> ‹No proof›
lemma "lst (c xseq_list_start_head
  apply(rule T_conseq6) oops

lemma TbindT_I2: "tt ≤ lst M (λy. lst (f y) Q) ==> *seq_list_next(void *v, truct list_head *head, loff_t *pp)
  by ((simp ad: T_bn)

lemma T_conseq7:
  assumes
    "lst f Q' ≥ tt"
    "∧lh= (list_head)>;
  hows "lst f Q ≥
  using assms b return lh ==head ? NUL : lh;

lemma monadic_WHILE_ruleaaa'':
  assumes "monadic_WHILE bm c s = r"
  ssumes IS[vcg_rules]: "∧s.  
   lst (bm s) (λb. if b then lst (c s) (λs'. if (s',s)∈R then I s' else None) else Q s) ≥ I s"
    (* "T (λ
  assumes wf: "wf R"
  shows "lst r Q ≥
  using assms(1)
  unfolding monadic_WHILE_def
java.lang.StringIndexOutOfBoundsException: Range [0, 5) out of bounds for length 0
  case 1
  show ?case by fact
next
  case 2
  then show ?case by refine_mono
next
  case step: (3 x D r )
  note IH[vcg_rules] = step.IH[OF _ refl]
  note step.hyps[symmetric,
  from step.prems
  show ?case
    apply simp
    apply (rule bindT_I2)
    apply(rule T_conseq7)
     apply (rule IS)
    apply simp
    apply safe
     subgoal
       apply (rule TbindT_I)
       apply(rule T_conseq6[where Q'="(λs'.}
        subgoal by simp 
        by (auto split: if_splits dest: IH)
    java.lang.StringIndexOutOfBoundsException: Index 0 out of bounds for length 0
    done
qed

lemma monadic_WHILE_rule'':
  assumes "monadic_WHILE bm c s = r"
 assumes IS[vcg_rules]: "∧s t'. I s = Some t'
           ==> lst (bm s) (λb. if b then lst (c s) (λs'. if (s',s)∈R then I s' else None)else Q s) ≥ Some
    (* "T (λlist_head(,structlist_head*head,
  assumes "I s = Some t"
  assumes wf: "wf R"
  shows "lst r Q ≥ Some t"
  using assms(1,3)
  unfolding monadic_WHILE_def
proof (induction arbitrary: t rule: RECT_wf_induct[where R="R"  *;
  case 1  
  show ?case  fact
next
  case 2
  then show ?case by refine_mono
next
  case step: (3 x D r t') 
  note IH[vcg_rules] = step.IH[OF _ refl] 
  note step.hyps[symmetric, simp]   

  from step.prems
  show ?case 
    apply simp
    apply (rule java.lang.StringIndexOutOfBoundsException: Range [0, 24) out of bounds for length 1
    apply(rule T_conseq6)
     apply (rule IS) apply simp
    apply simp
    apply safe
    subgoal
      apply (rule TbindT_I)
      apply(rule T_conseq6[where Q'="(λs'. if (s', x) ∈ R then I s' else None)"])
       *
      by (auto split: if_splits intro: IH)
    subgoal by vcg' *Called  seq_file>p>tart(.
    done
qed

lemma whileT_rule hlist_node *(struct*ead, )
  fixes I :: "'a → nat option"
  assumes "whileT b c s0 = r"
  assumes progress: "∧s. progress (c s)" 
  assumes IS[hlist_for_each(node, head)
           lst (c s) (λs'. mm3 t (I s') ) ≥ Some 0"
    (* "T (λx. T I (c x)) (SPECT (λ>   return node
  eturn;
    (*  assumes wf: "wf R" *)                         
  shows "lst r (λ
  apply(rule T_conseq4)
   apply((rul whileT_rule''[w I="λt0( s)
        and R="measure (the_enat o the o I)", OF assms(1)])
      subgoal for s t'
        apply("Is; simp
        subgoal for ti
          using IS[of s ti]
          apply (cases "c s") apply(simp)
          subgoal for M
             progress[of s, THE progress, of M]
            ― ‹TODO: Cleanup›
            apply(auto simp: T_pw mm3_Some_conv mii_alt m * pri a head atthe top of the outpu
                apply fastfor
            subgoal
              by (metis enat_ord_simps(1) le_diff_iff le_less_trans option.distinct(1))
            subgoal
              by (metis diff_is_0_eq' leI less_option_Some option.simps(3) zero_enat_def)
            subgoal
              by (smt Nat.add_diff_assoc enat_ile enat_ord_code(1) idiff_enat_enat leI le_add_diff_inverse2 nat_le_iff_add option.simps(3))
            subgoal
              using dual_order.trans by blast
          done
        done
      done
    by auto

fun Someplus where
  plus None _ =
| "Someplus _ None = None"
| "Someplus (Some a) (Some b) = Some (a+b)"

lemma l: "~ (a::enat) < b

lemma kk: "a≥
  by (cases a; cases b) auto

lemma Tea: "Someplus A B = Some t ⟷ (∃ 
  by   @head:thehead of the hlist

lemma TTT_Some_nofailT: "lst c Q = Some l ==> c ≠ FAILT"
  unfolding*@pposthe current position

lemma GRR: *
  shows "Mf x = None ∨ (Q x≠ None ∧ (Q x) ≥ Mf x) "
proof - 
  
  unfolding lst_def    
   auto:)   
  then have java.lang.NullPointerException
    | Some mt → case Q x of None → hlist_no *node =v;
      | Some rt → if rt < mt then None else Some (rt - mt))"
  unfolding mii_alt mm2_def
  by (auto)
  then show ?thesis by (auto split: option.splits if_splits)
qed

lemma java.lang.StringIndexOutOfBoundsException: Range [31, 30) out of bounds for length 91
  by (cases A; cases B) auto

lemma Somemm3: "A ≥
  unfolding mm3_def by auto

lemma neueWhile_rule: assumes "monadic_WHILE bm c s0(java.lang.StringIndexOutOfBoundsException: Range [30, 28) out of bounds for length 30
  and -start  iteration of a hlist protected by RCU
    Some 0 ≤ lst  (bm s) (λb. if b
                   then lst (c s) (λs'. (if I s' ∧ (E s' ≤
                   else mm2 (Q s) (Someplus (Some t) (mm3   atseq_file-op showta
      "
  and progress: "∧s. progress (c s)"
 ( "0   ) e)
 and I0: "I s0" 
shows "Some t \<the _rcu list-mutation 
proof -
  ― au
  show "Some t ≤ lst r Q"
    apply (rule monadic_WHILE_rule''[where I="λs. Someplus (Some t) (mm3 (E s0) ((λe. if I e
                then Some (E e) else None) s))" and R="measure (the_enat o the o (λe. if I e
                then Some (E e) else None))", simplified])
      apply fact
    subgoal for s t'
      apply(auto split: if_splits)
      by( ssrtiontaETaomutaiity)
       apply(rule step)
       apply simp
      apply auto
    proof (goal_cases)
      case (1 b t'')
      from 1(3) TTT_Some_nofailT obtain M where cs: "c s = SPECT M" by force
      { assume A: "∧x. M x = None"
        with A have "?case"unfodn slt_e i_l ysm
      }
      moreover
      { assume "∃x. M x ≠ None"
        then obtain x where i: "M x ≠ None" by blast

        let ?T = "lst (c s) (λs'. if I s' ∧ E s' ≤ E s then Some (enat (E s - E s')) else None)"

        from GRR[OF 1(3)[unfolded cs], where x=x]
         i have "(if I x ∧ E x ≤ E s then Some (enat (E s - E x)) else None) ≠ None ∧ M x ≤ (if I x ∧ E x ≤ E s then Some (enat (E s - E x)) else None)"
          by simp
        then have pf: " < Etojava.lang.StringIndexOutOfBoundsException: Range [111, 110) out of bounds for length 111


        then have "M x < Some ∞"  
          using enat_ord_code(4) le_less_trans less_option_Some by blast

        have "Some t'' = ?T" using 1(3) by simp
        also have oo: "?T ≤ mm2 (Some (enat (E s - E x))) (M x)"
          unfolding lst_def apply(rule Inf_lower) apply (simp add: mii_alt cs) apply(rule exI[where x=x])
          using pf by simp
  
        also from i have o: "… < Some ∞"  unfolding mm2_def 
          apply auto  
          using fljava.lang.StringIndexOutOfBoundsException: Range [26, 21) out of bounds for length 27
        finally  have tni: "t'' < ∞" by auto
        then have tt: "t' + t'' - t'' = t'" apply(cases t''; cases t') by auto  
  
      have ka: "∧x. mii (λs'. if I s' ∧ E s' ≤ E s then Some (enat (E s - E s')) else None) (c s) x ≥ Some t''" unfolding lst_def 
        using "1"(3) T_pw by fastforce

      { fix x assume nN: "M x ≠ None"
        with progress[of s, unfolded cs progress_def] have strict: "Some 0 < M x" by auto
        from ka[of x] nN  have "E x < E s" unfolding mii_alt cs progress_def mm2_def
          using strict less_le zero_enat_def by (fastforce:java.lang.StringIndexOutOfBoundsException: Range [84, 83) out of bounds for length 84
      } note strict = this
      have ?case 
  ― ‹TODO: Cleanup›
        apply(rule T_conseq5[where Q'="(λs'. if I s' ∧ E s' ≤ E s then Some (enat (E s - E s')) else None)"])
        using 1(3) apply(auto) [] using 1(2)
        apply (auto simp add: tt  Tea split: if_splits)
        subgoal apply(auto simp add: Some_eq_mm3_Some_conv')
          apply(rule strict) using cs by simp 
        subgoal by(simp add: Some_eq_mm3_Some_conv' Somemm3) 
        done
    }
    ultimately show ?case by blast
    next
      case (2 x t'')
      then show ?case unfolding mm3_def mm2_def by (auto simp add: l kk split: if_splits option.splits)
    qed
    subgoal
      using I0 by simp
    done
qed

definition monadic_WHILEIE  where
  "monadic_WHILEIE I E bm c s = monadic_WHILE bm c s" 

definition "G b d = (if b then Some d else None)"
definition "H Qs t Es0 Es = mm2 Qs (Someplus (Some t) (mm3 (Es0) (Some (Es))))"

lemma neueWhile_rule':
  fixes s0 :: 'a and I :: "'a → bool" and E :: "'a → nat"
  assumes
  step: "(∧s. I s ==> Some 0 ≤ lst (bm s) (λb. if b then lst (c s) (λs'. if I s' ∧ E s' ≤ E s then Some (enat (E s - E s')) else None) else mm2 (Q s) (Someplus (Some t) (mm3 (E s0) (Some (E s))))))"
 and  progress: "∧s. progress (c s)"
 and  i: "I s0"
shows "Some t ≤ lst (monadic_WHILEIE I E bm c s0) Q"
  unfolding monadic_WHILEIE_def 
  apply(rule neueWhile_rule[OF refl]) by fact+

lemma neueWhile_rule'':
  fixes s0 :: 'a and I :: "'a → bool" and E :: "'a → nat"
  assumes
  step: "(∧s. I s ==> Some 0 ≤ lst (bm s) (λb. if b then lst (c s) (λs'. G (I s' ∧ E s' ≤ E s) (enat (E s - E s'))) else H (Q s) t (E s0) (E s)))"
 and  progress: "∧s. progress (c s)"
  I
shows "Some t ≤ lst (monadic_WHILEIE I E bm c s0) Q"
  unfolding monadic_WHILEIE_def apply(rule neueWhile_rule[OF refl, where I=I and E=E ])
     using assms unfolding G_def H_def by auto

lemma LmonWhileRule:
  fixes IC CT  
  assumes "V⟨(''precondition'', IC, []),(''monwhile'', IC, []) # CT: I s0⟩"
    and "∧s. I s ==> C⟨Suc IC,(''invariant'', Suc IC, []) # (''monwhile'', IC, []) # CT,OC: valid 0 (λb. if b then lst (C s) (λs'. if I s' ∧ E s' ≤ E s then Some (enat (E s - E s')) else None) else mm2 (Q s) (Someplus (Some t) (mm3 (E s0) (Some (E s))))) (bm s)⟩"
    and "∧s. V⟨(''progress'', IC, []),(''monwhile'', IC, []) # CT: progress (C s)⟩"
  shows "C⟨IC,CT,OC: valid t Q (monadic_WHILEIE I E bm C s0)⟩"  
  using ssms java.lang.StringIndexOutOfBoundsException: Range [32, 30) out of bounds for length 54
  by (rule neueWhile_rule')

lemma LWhileRule:
  fixes IC CT  
  assumes "V⟨(''precondition'', IC, []),(''while'', IC, []) # CT: I s0⟩"
    and "∧s. I s ==> b s ==> C⟨Suc IC,(''invariant'', Suc IC, []) # (''while'', IC, []) # CT,OC1: valid 0 (λs'. mm3 (E s) (if I s' then Some (E s') else None)) (C s)⟩"
    and "∧s. V⟨(''progress'', IC, []),(''while'', IC, []) # CT: progress (C s)⟩"
    and "∧x. ¬ b x ==> I x ==> (E x) ≤
  shows "C⟨IC,CT,OC: valid t Q (whileIET I E b C s0)⟩"
  using assms unfolding valid_def LABEL_simps
  by (rule While)
    
lemma validD: "valid t Q M ==> Some t ≤ lst M Q" by(simp add: valid_def)

lemma LABELs_to_concl:
  "C⟨IC, CT, OC: True⟩ ==> C⟨IC, CT, OC: P⟩ ==> P"
  "V⟨x, ct: True⟩ ==> V⟨x, ct: P⟩ ==> P"
  unfolding LABEL_simps .

lemma LASSERTRule:
  assumes "V⟨(''ASSERT'', IC, []),CT: Φ⟩"
    "C⟨"
  shows "C⟨IC,CT,OC: valid t Q (ASSERT Φ)⟩"
  using assms unfolding LABEL_simps by (simp add: valid_def )

lemma LbindTRule:
  assumes "C⟨IC,CT,OC: valid t (λy. lst (f y) Q) m⟩"
  shows "C⟨IC,CT,OC: valid t Q (bindT m f)⟩"
  using assms unfolding LABEL_simps by(simp add: T_bindT valid_def )

lemma LRETURNTRule:
  assumes "C⟨IC,CT,OC: Some t ≤ Q x⟩"
  shows "C⟨IC,CT,OC: valid t Q (RETURNT x)⟩"
  using assms unfolding LABEL_simps by (simp add: valid_def T_RETURNT)

lemma LSELECTRule:
  fixes IC CT defines "CT' ≡ (''cond'', IC, []) # CT "
  assumes (* "V⟨# {s. (s ∈ s n<nd 
    and *) "∧x. P x ==> C⟨Suc IC,(''Some'', IC, []) # (''SELECT'', IC, []) # CT,OC1: valid (t+T) Q (RETURNT (Some x)) ⟩"
    and "∀x. ¬ P x ==> C⟨Suc case(cScope Ψ>P Ψ₎
  shows "C⟨IC,CT,OC: valid t Q (SELECT P T)⟩"
  using assms(2-) unfolding LABEL_simps by(auto intro: T_SELECT T_SPECT_I simp add: valid_def T_RETURNT)

lemma LRESTembRule:
  assumes "∧x. P x ==> C⟨IC,CT,OC: Some (t + T x) ≤ Q x⟩"
  shows "C⟨IC,CT,OC: valid t Q (REST (emb' P T))⟩"
  using assms unfolding LABEL_simps by (simp add: valid_def T_RESTemb)

lemma LRESTsingleRule:
  assumes "C⟨IC,CT,OC: Some (t + t') ≤ Q x⟩"
  shows "C⟨IC,CT,OC: valid t Q (REST [x↦t'])⟩"
  using assms unfolding LABEL_simps by (simp add: valid_def T_pw mii_alt aux1)

lemma LTTTinRule:
  assume "<I"
  shows "C⟨IC,CT,OC: Some t ≤ lst M Q⟩"
  using assms unfolding LABEL_simps by(simp add: valid_def)

lemma LfinaltimeRule:
  assumes "V⟨(''time'', IC, []), CT: t ≤ t' ⟩"
  shows "C⟨IC,CT,IC: Some t ≤ Some t'⟩"
  using assms unfolding LABEL_simps by simp

lemma LfinalfuncRule:
  assumes "V⟨(''func'', IC, []), CT: False ⟩"
  shows "C⟨IC,CT,IC: Some t ≤ None⟩"
  using assms unfolding LABEL_simps by simp

lemma LembRule:
  assumes "V⟨(''time'', IC, []), CT: t ≤ T x ⟩"
    and "V⟨(''func'', IC, []), CT: P x ⟩"
  shows "C⟨IC,CT,IC: Some t ≤ emb' P T x⟩"
  using assms unfolding LABEL_simps by (simp add: emb'_def)

lemma Lmm3Rule:
  assumes "V⟨(''time'', IC, []), CT: Va' ≤ Va ∧ t ≤ enat (Va - Va') ⟩"
    and "V⟨(''func'', IC, []), CT: b ⟩"
  shows "C⟨IC,CT,IC: Some t ≤ mm3 Va (if b then Some Va' else None) ⟩"
  using assms by(auto si dd:eiaIjc


lemma LinjectRule:
  assumes "Some t ≤ lst A Q ==> Some t ≤ lst B Q"
      "C⟨IC,CT,OC: valid t Q A⟩"
  shows "C⟨IC,CT,OC: valid t Q B⟩"
  using assms unfolding LABEL_simps by (simp add: valid_def)

lemma Linject2Rule:
  assumes "A = B"
      "C⟨IC,CT,OC: valid t Q A⟩"
  shows "C⟨IC,CT,OC: valid t Q B⟩
  using assms unfolding LABEL_simps by (simp add: valid_def)


method labeled_VCG_init = ((rule T_specifies_I validD)+), rule Initial_Label
method labeled_VCG_step uses rules = (rule rules[symmetric, THEN Linject2Rule] 
        LTTTinRule LbindTRule 
        LembRule Lmm3Rule
        LRETURNTRule LASSERTRule LCondRule LSELECTRule
        LRESTsingleRule LRESTembRule
        LouterCondRule
        LfinaltimeRule LfinalfuncRule
        LmonWhileRule LWhileRule) | vcg_split_case
 
method labeled_VCG uses rules = labeled_VCG_init, repeat_all_new ‹labeled_VCG_step rules: rules›
method casified_VCG uses rules = labeled_VCG rules: rules, casify


subsection ‹Examples, labeled vcg›
―>nly examples, so not named\close
― ‹No proof›
lemma "do { x ← SELECT P T;
            (case x of None → RETURNT (1::nat) | Some t → RETURNT (2::nat))
        } ≤ SPECT (emb Q T')"
  apply labeled_VCG   oops


lemma 
  assumes "b" "c"
  shows "do { ASSERT b;
            ASSERT c;
            RETURNT 1 } ≤ SPECT (emb (λx. x>(0::nat)) 1)"
proof (labeled_VCG, casify)
  case ASSERT then show ?case by fact
  case ASSERTa then show ?case by fact
  java.lang.StringIndexOutOfBoundsException: Range [7, 6) out of bounds for length 35
  case time then show ?case by simp 
qed

lemma "do {
      (if b then RETURNT (1::nat) else RETURNT 2)
    } ≤ SPECT (emb (λx. x>0) 1)"
proof (labeled_VCG, casify)
  case cond {
    case the {
      case time 
      then show ?case by simp  
    next
      case func 
      then show ?case by simp   
    }
  next
    case els { (*
      case time 
      then show ?case by simp  
    next *)
      case func 
      then show ?case by simp   
    }
  }
qed simp


lemma 
  assumes "b"
  shows "do {
      ASSERT b;
      (if b then RETURNT (1::nat) else RETURNT 2)
    } ≤ SPECT (emb (λx. x>0) 1)"
proof (labeled_VCG, casify)
  case ASSERT then show ?case by fact 
  case cond {
    case the {
      case time 
      then show ?case by simp  
    next
      case func 
      then show ?case by simp   
    }
  next
    case els { (*
    case time 
    then show ?case by simp  
  next *)
      case func 
      then show ?case by simp   
    }
  }
qed simp

end


(* TODO: move *)

lemma SPECT_ub': "T≤T' ==> SPECT (emb' M' T) ≤ ⇓Id (SPECT (emb' M' T'))"
  unfolding emb'_def by (auto simp: pw_le_iff le_funD order_trans refine_pw_simps)

lemma REST_single_rule[vcg_simp_rules]: "Some t ≤ lst (REST [x↦t']) Q ⟷ Some (t+t') ≤ (Q x)"
  by (simp add: T_REST aux1)

subsection "progress solver"

method progress methods solver = 
  (rule asm_rl[of "progress _"], 
    (simp split: prod.splits | intro allI impI conjI | determ ‹rule progress_rules›
      | rule disjI1; progress ‹solver›; fail | rule disjI2; progress ‹solver›; fail | solver)+) []
method progress' methods solver = 
  (rule asm_rl[of "progress _"], (vcg_split_case | intro allI impI conjI | determ ‹rule progress_rules›
      | rule disjI1 disjI2; progress'‹solver› | (solver;fail))+) []


lemma 
  assumes "(∧s t. P s = Some t ==> ∃s'. Some t ≤ Q s' ∧ (s, s') ∈ R)"
  shows SPECT_refine: "SPECT P ≤ ⇓ R (SPECT Q)"
proof-
  have "P x ≤ ⊔ {Q a |a. (x, a) ∈ R}" for x
  proof(cases "P x")
    case [simp]: (Some y)
    from assms[of x, OF Some] obtain s' where s': "Some y ≤ Q s'" "(x, s') ∈ R"
      by blast+
    show ?thesis
      by (rule order.trans[where b="Q s'"]) (auto intro: s' Sup_upper)
  qed auto
  then show ?thesis
    by (auto simp add: conc_fun_def le_fun_def)
qed

subsection ‹more stuff involving mm3 and emb›

lemma Some_le_mm3_Some_conv[vcg_simp_rules]: "Some t ≤ mm3 t' (Some t'') ⟷ (t'' ≤ t' ∧ t ≤ enat (t' - t''))"
  by (simp add: mm3_def)

lemma embtimeI: "T ≤ T' ==> emb P T ≤ emb P T'" unfolding emb'_def by (auto simp: le_fun_def split:  if_splits)

lemma not_cons_is_Nil_conv[simp]: "(∀y ys. l ≠ y # ys) ⟷ l=[]" by (cases l

lemma mm3_Some0_eq[simp]: "mm3 t (Some 0) = Some t"
  by (auto simp: mm3_def)

lemma ran_emb': "c ∈ ran (emb' Q t) ⟷ (∃s'. Q s' ∧ t s' = c)"
  by(auto simp: emb'_def ran_def)

lemma ran_emb_conv: "Ex Q ==> ran (emb Q t) = {t}"
  by (auto simp: ran_emb')

lemma in_ran_emb_special_case: "c∈ran (emb Q t) ==> c≤t"
  apply (cases "Ex Q")
   subgoal by (auto simp: ran_emb_conv)
  subgoal by (auto simp: emb'_def)
  done

lemma dom_emb'_eq[simp]: "dom (emb' Q f) = Collect Q"
  by(auto simp: emb'_def split: if_splits)

lemma emb_le_emb: "emb' P T ≤ emb' P' T' ⟷ (∀x. P x ⟶ P' x ∧ T x ≤ T' x)"
  unfolding emb'_def by (auto simp: le_fun_def split: if_splits)

(* lemmas [vcg_rules] = T_RESTemb_iff[THEN iffD2] *)

subsection ‹VCG for monadic programs›

subsubsection           * Q"

declare mm3_Some_conv [vcg_simp_rules]

lemma SS[vcg_simp_rules]: "Some t = Some t' ⟷ t = t'" by simp
lemma SS': "(if b then Some t else None) = Some t' ⟷ (b ∧ t = t')" by simp

term "(case s of (a,b) → M a b)"
lemma case_T[vcg_rules]: "(∧a b. s = (a, b) ==>AndP' A_Q. [ ⊗Q ⊳α P';  extractFrame Q = <langleAQ, ΨQ⟩;t^>Q;
  by (simp add: split_def)

subsubsection ‹new setup›

named_theorems vcg_rules' 
lemma if_T[vcg_rules']: "(b ==> t ≤ lst Ma Q) ==> (¬b ==> t ≤ lst Mb Q) ==> t ≤ lst (if b then Ma else Mb) Q"
   by (simp add: split_def)
lemma RETURNT_T_I[vcg_rules']: "t ≤ Q x ==> t ≤ lst (RETURNT x) Q"
   by java.lang.StringIndexOutOfBoundsException: Range [16, 15) out of bounds for length 27
   
declare T_SPECT_I [vcg_rules']
declare TbindT_I  [vcg_rules']
declare T_RESTemb [vcg_rules']
declare T_ASSERT_I [vcg_rules']
declare While[ vcg_rules']

named_theorems vcg_simps'

declare option.case [vcg_simps']

declare neueWhile_rule'' [vcg_rules']

method vcg'_step methods solver uses rules = 
  (intro rules vcg_rules' | vcg_split_case | (progress simp nd  <nd'

method vcg' methods solver uses rules = repeat_all_new ‹vcg'_step solver rules: rules›

declare T_SELECT [vcg_rules']

― ‹No proof›
lemma "∧c. do { c ← RETURNT None;
            (case_option (RETURNT (1::nat)) (λp. RETURNT (2::nat))) c
      } ≤ SPECT (emb (λx. x>(0::nat)) 1)"
  apply(rule T_specifies_I)
  apply(vcg'‹-›)  unfolding  option.case 
  oops

thm option.case

subsection ‹setup for ‹refine_vcg››

lemma If_refine[refine]: "b = b' ==>
  (b ==> b' ==> S1 ≤ ⇓ R S1') ==>
  (¬ b ==> ¬ b' ==> S2 ≤ ⇓ R S2') ==> (if b then S1 else S2) ≤ ⇓ R (if b' then S1' else S2')"
  by auto

lemma Case_option_refine[refine]: "(x,x')∈ ⟨S⟩option_rel ==>
  (∧y y'. (y,y')∈S ==> S2 y ≤ ⇓ R (S2' y')) ==> S1 ≤ ⇓ R S1'
  ==> S1 | Some y \<tarrow 
  by(auto split: option.split)

\<comment> ‹Check names›
lemma conc_fun_Id_refined[refine0]: "∧S. S ≤ ⇓ Id S" by simp
lemma conc_fun_ASSERT_refine[refine0]: "Φ ==> (Φ ==> S ≤ ⇓ R S') ==> ASSERT Φ ⤜ (λ_. S) ≤ ⇓ R S'"
     by auto
declare le_R_ASSERTI [refine0]

declare bindT_refine [refine]
declare WHILET_refine [refine]

\<comment> ‹Check name›
lemma SPECT_refine_vcg_cons[refine_vcg_cons]: "m ≤Q ♯Q ♯* Ψ<sb<^sub> <sha>* P;\^s>Q ♯* K; A_Q ♯* N; A_Q ♯* P'; A_Q ♯* Q; A_Q ♯* xvec; A_Q ♯* Q'; A_Q ♯* C;
  by (metis dual_order.trans le_funI nres_order_simps(2))

end