Section Code_Substitute_Formula.
Variable L : Language.
Variable codeF : Functions L -> nat.
Variable codeR : Relations L -> nat.
Notation Formula := (Formula L) (only parsing).
Notation Formulas := (Formulas L) (only parsing).
Notation System := (System L) (only parsing).
Notation Term := (Term L) (only parsing).
Notation Terms := (Terms L) (only parsing).
Let var := var L.
Let apply := apply L.
Let codeFormula := codeFormula L codeF codeR.
Let codeTerm := codeTerm L codeF.
Definition cTriple (a b c : nat) : nat := cPair a (cPair b c).
Definition cTriplePi1 (n : nat) : nat := cPairPi1 n.
Definition cTriplePi2 (n : nat) : nat := cPairPi1 (cPairPi2 n).
Definition cTriplePi3 (n : nat) : nat := cPairPi2 (cPairPi2 n).
unfold cTriplePi1, cTriple in |- *.
intros.
apply cPairProjections1.
Qed.
unfold cTriplePi2, cTriple in |- *.
intros.
rewrite cPairProjections2.
apply cPairProjections1.
Qed.
unfold cTriplePi3, cTriple in |- *.
intros.
rewrite cPairProjections2.
apply cPairProjections2.
Qed.
(*Trace has form ((v,s, formula_input), formula_output, [subTrace1], [subTrace2])*)
Definition codeNewVar (l : nat) : nat :=
evalStrongRec 0
(fun n Hrecs : nat =>
switchPR n
(max (S (cPairPi1 (pred n)))
(codeNth (n - S (cPairPi2 (pred n))) Hrecs)) 0) l.
Definition checkSubFormulaTrace : nat -> nat :=
evalStrongRec 0
(fun trace recs : nat =>
let v := cTriplePi1 (cTriplePi1 trace) in
let s := cTriplePi2 (cTriplePi1 trace) in
let input := cTriplePi3 (cTriplePi1 trace) in
let output := cTriplePi2 trace in
let rest := cTriplePi3 trace in
let type := cPairPi1 input in
switchPR type
(switchPR (pred type)
(switchPR (pred (pred type))
(switchPR (pred (pred (pred type)))
(charFunction 2 beq_nat output
(cPair type (codeSubTerms (cPairPi2 input) v s)))
(switchPR
(charFunction 2 beq_nat v (cPairPi1 (cPairPi2 input)))
(charFunction 2 beq_nat input output)
(switchPR
(codeIn (cPairPi1 (cPairPi2 input)) (codeFreeVarTerm s))
(let nv :=
codeNewVar
(S
(cPair v
(codeApp (codeFreeVarTerm s)
(codeFreeVarFormula
(cPairPi2 (cPairPi2 input)))))) in
charFunction 0
(beq_nat output
(cPair 3 (cPair nv (cTriplePi2 (cPairPi2 rest)))) &&
(beq_nat (cTriple v s (cTriplePi2 (cPairPi1 rest)))
(cTriplePi1 (cPairPi2 rest)) &&
beq_nat
(cTriple (cPairPi1 (cPairPi2 input))
(cPair 0 nv) (cPairPi2 (cPairPi2 input)))
(cTriplePi1 (cPairPi1 rest)))) *
(codeNth (trace - S (cPairPi1 rest)) recs *
codeNth (trace - S (cPairPi2 rest)) recs))
(charFunction 0
(beq_nat output
(cPair 3
(cPair (cPairPi1 (cPairPi2 input))
(cTriplePi2 rest))) &&
beq_nat (cTriple v s (cPairPi2 (cPairPi2 input)))
(cTriplePi1 rest)) *
codeNth (trace - S rest) recs))))
(charFunction 0
(beq_nat output (cPair 2 (cTriplePi2 rest)) &&
beq_nat (cTriple v s (cPairPi2 input)) (cTriplePi1 rest)) *
codeNth (trace - S rest) recs))
(charFunction 0
(beq_nat output
(cPair 1
(cPair (cTriplePi2 (cPairPi1 rest))
(cTriplePi2 (cPairPi2 rest)))) &&
(beq_nat (cTriple v s (cPairPi1 (cPairPi2 input)))
(cTriplePi1 (cPairPi1 rest)) &&
beq_nat (cTriple v s (cPairPi2 (cPairPi2 input)))
(cTriplePi1 (cPairPi2 rest)))) *
(codeNth (trace - S (cPairPi1 rest)) recs *
codeNth (trace - S (cPairPi2 rest)) recs)))
(charFunction 2 beq_nat output
(cPair 0
(cPair (codeSubTerm (cPairPi1 (cPairPi2 input)) v s)
(codeSubTerm (cPairPi2 (cPairPi2 input)) v s))))).
Definition makeTraceImp (f1 : fol.Formula L)
(f1rec : nat * fol.Term L -> nat) (f2 : fol.Formula L)
(f2rec : nat * fol.Term L -> nat) (p : nat * fol.Term L) : nat :=
let v := fst p in
let s := snd p in
cTriple (cTriple v (codeTerm s) (codeFormula (impH L f1 f2)))
(codeFormula (substituteFormula L (impH L f1 f2) v s))
(cPair (f1rec p) (f2rec p)).
Definition makeTraceNot (f : fol.Formula L) (frec : nat * fol.Term L -> nat)
(p : nat * fol.Term L) : nat :=
let v := fst p in
let s := snd p in
cTriple (cTriple v (codeTerm s) (codeFormula (notH L f)))
(codeFormula (substituteFormula L (notH L f) v s))
(frec p).
Definition makeTraceForall (n : nat) (f : fol.Formula L)
(rec : forall b : fol.Formula L,
lt_depth L b (forallH L n f) -> nat * fol.Term L -> nat)
(p : nat * fol.Term L) : nat.
intros.
set (v := fst p) in *.
set (s := snd p) in *.
induction (eq_nat_dec n v).
exact
(cTriple (cTriple v (codeTerm s) (codeFormula (forallH L n f)))
(codeFormula (substituteFormula L (forallH L n f) v s)) 0).
assert (lt_depth L f (forallH L v f)).
apply depthForall.
induction (In_dec eq_nat_dec n (freeVarTerm L s)).
set (nv := newVar (v :: freeVarTerm L s ++ freeVarFormula L f)) in *.
assert (lt_depth L (substituteFormula L f n (var nv)) (forallH L v f)).
apply eqDepth with f.
symmetry  in |- *.
apply subFormulaDepth.
apply H.
exact
(cTriple (cTriple v (codeTerm s) (codeFormula (forallH L n f)))
(codeFormula (substituteFormula L (forallH L n f) v s))
(cPair (rec f H (n, var nv))
(rec (substituteFormula L f n (var nv)) H0 p))).
exact
(cTriple (cTriple v (codeTerm s) (codeFormula (forallH L n f)))
(codeFormula (substituteFormula L (forallH L n f) v s))
(rec f H p)).
Defined.
Definition makeTrace : fol.Formula L -> nat * fol.Term L -> nat :=
Formula_depth_rec2 L (fun _ : fol.Formula L => nat * fol.Term L -> nat)
(fun (t t0 : fol.Term L) (p : nat * fol.Term L) =>
let v := fst p in
let s := snd p in
cTriple (cTriple v (codeTerm s) (codeFormula (equal L t t0)))
(codeFormula (substituteFormula L (equal L t t0) v s)) 0)
(fun (r : Relations L) t (p : nat * fol.Term L) =>
let v := fst p in
let s := snd p in
cTriple (cTriple v (codeTerm s) (codeFormula (atomic L r t)))
(codeFormula (substituteFormula L (atomic L r t) v s)) 0) makeTraceImp
makeTraceNot makeTraceForall.
Remark makeTrace1 :
forall (f : fol.Formula L) (v : nat) (s : fol.Term L),
cTriplePi1 (makeTrace f (v, s)) = cTriple v (codeTerm s) (codeFormula f).
Remark makeTrace2 :
forall (f : fol.Formula L) (v : nat) (s : fol.Term L),
cTriplePi2 (makeTrace f (v, s)) = codeFormula (substituteFormula L f v s).

Lemma checkTraceCorrect :
forall (f : fol.Formula L) (v : nat) (s : fol.Term L) (n m : nat),
checkSubFormulaTrace (cTriple (cTriple v (codeTerm s) (codeFormula f)) n m) <>
0 -> codeFormula (substituteFormula L f v s) = n.