import vec:*
import vec_literals:*
import map:*
import set:*
import util:*
import str:*
import regex:*

// nonterminals are negative, terminals are positive
obj Grammer<T,K> (Object) {
    var nonterminals: vec<vec<vec<int>>>
    var nonterminal_names: vec<str>
    var nonterminal_funs: vec<vec<pair<K,fun(ref K, ref vec<T>): T>>>
    var terminals: vec<regex>
    var terminal_funs: vec<pair<K,fun(ref K,ref str,int,int): T>>
    var start_symbol: int
    fun construct(): *Grammer {
        nonterminals.construct()
        nonterminal_names.construct()
        nonterminal_funs.construct()
        terminals.construct()
        terminal_funs.construct()
        start_symbol = 0
        return this
    }
    fun copy_construct(old: *Grammer): void {
        nonterminals.copy_construct(&old->nonterminals)
        nonterminal_names.copy_construct(&old->nonterminal_names)
        nonterminal_funs.copy_construct(&old->nonterminal_funs)
        terminals.copy_construct(&old->terminals)
        terminal_funs.copy_construct(&old->terminal_funs)
        start_symbol = old->start_symbol
    }
    fun destruct(): void {
        nonterminals.destruct()
        nonterminal_names.destruct()
        nonterminal_funs.destruct()
        terminals.destruct()
        terminal_funs.destruct()
    }
    fun operator=(other:ref Grammer):void {
        destruct()
        copy_construct(&other)
    }
    fun add_new_nonterminal(name: *char, rule: ref vec<int>, d: K, f: fun(ref K,ref vec<T>): T): int {
        return add_new_nonterminal(str(name), rule, d, f)
    }
    fun add_new_nonterminal(name: ref str, rule: ref vec<int>, d: K, f: fun(ref K,ref vec<T>): T): int {
        nonterminals.add(vec(rule))
        nonterminal_names.add(name)
        nonterminal_funs.add(vec(make_pair(d,f)))
        return -1*nonterminals.size
    }
    fun add_to_or_create_nonterminal(name: ref str, rule: ref vec<int>, d: K, f: fun(ref K,ref vec<T>): T): int {
        var idx = nonterminal_names.find(name)
        if idx >= 0 {
            add_to_nonterminal(-1*(idx+1), rule, d, f)
            return -1*(idx+1)
        } else {
            return add_new_nonterminal(name, rule, d, f)
        }
    }
    fun add_to_nonterminal(nonterminal: int, rule: ref vec<int>, d: K, f: fun(ref K,ref vec<T>): T) {
        nonterminals[(-1*nonterminal)-1].add(rule)
        nonterminal_funs[(-1*nonterminal)-1].add(make_pair(d,f))
    }
    fun add_terminal(c: *char, d: K, f: fun(ref K,ref str,int,int): T): int {
        return add_terminal(str(c), d, f)
    }
    fun add_terminal(c: ref str, d: K, f: fun(ref K,ref str,int,int): T): int {
        terminals.add(regex(c))
        terminal_funs.add(make_pair(d,f))
        return terminals.size
    }
    fun get_nonterminal_rules(nonterminal: int): ref vec<vec<int>> {
        return nonterminals[(-1*nonterminal)-1]
    }
    fun match_terminal(terminal: int, input: ref str, start: int): int {
        return terminals[terminal-1].long_match(input.getBackingMemory(), start, input.length())
    }
    fun is_terminal(x: int): bool {
        return x > 0
    }
    fun set_start_symbol(x: int) {
        start_symbol = x
    }
    fun to_string(it: BS): str {
        var rule_str = str()
        for (var i = 0; i < nonterminals[(-1*it.nonterminal)-1][it.rule_idx].size; i++;) {
            if i == it.idx_into_rule {
                rule_str += "*"
            }
            var erminal = nonterminals[(-1*it.nonterminal)-1][it.rule_idx][i]
            rule_str += to_string(erminal)
            if i < nonterminals[(-1*it.nonterminal)-1][it.rule_idx].size-1 {
                rule_str += " "
            }
        }
        if it.idx_into_rule == nonterminals[(-1*it.nonterminal)-1][it.rule_idx].size {
            rule_str += "*"
        }
        return str("<") + nonterminal_names[(-1*it.nonterminal)-1] + " ::= " + rule_str + ", "  + it.left + ", " + it.pivot + ", " + it.right + ">"
    }
    fun to_string(erminal: int): str {
        if erminal < 0 {
            return nonterminal_names[(-1*erminal)-1]
        } else {
            return terminals[erminal-1].regexString
        }
    }
    fun eval_BSR(input: ref str, BSR: ref set<BS>): T {
        var top = -1
        for (var i = 0; i < BSR.data.size; i++;) {
            if BSR.data[i].nonterminal == start_symbol && BSR.data[i].idx_into_rule == nonterminals[(-1*BSR.data[i].nonterminal)-1][BSR.data[i].rule_idx].size && BSR.data[i].left == 0 && BSR.data[i].right == input.length() {
                top = i
                break
            }
        }
        if top == -1 {
            println("Could not find top for input:")
            println(input)
            println(str("of length ") + input.length())
            for (var i = 0; i < BSR.data.size; i++;) {
                println(str() + i + ": " + to_string(BSR.data[i]))
            }
            error("Could not find top")
        }
        return eval_BSR(input, BSR, top)
    }
    fun eval_BSR(input: ref str, BSR: ref set<BS>, c: int): T {
        var bs = BSR.data[c]
        var nonterminal = (-1*bs.nonterminal)-1
        if bs.idx_into_rule != nonterminals[nonterminal][bs.rule_idx].size {
            error("Evaluating BSR from not the end!")
        }
        var params = vec<T>()
        for (var i = bs.idx_into_rule-1; i >= 0; i--;) {
            var erminal = nonterminals[nonterminal][bs.rule_idx][i]
            if is_terminal(erminal) {
                var right_value = terminal_funs[erminal-1].second(terminal_funs[erminal-1].first, input, bs.pivot, bs.right)
                params.add(right_value)
            } else {
                /*var right = find_comp(erminal, bs.pivot, bs.right)*/
                var right = -1
                var sub_nonterminal_idx = (-1*erminal)-1
                for (var j = 0; j < BSR.data.size; j++;) {
                    if BSR.data[j].nonterminal == erminal && BSR.data[j].idx_into_rule == nonterminals[sub_nonterminal_idx][BSR.data[j].rule_idx].size && BSR.data[j].left == bs.pivot && BSR.data[j].right == bs.right {
                        right = j
                        break
                    }
                }
                var right_value = eval_BSR(input, BSR, right)
                params.add(right_value)
            }
            // get the new left bs
            if i != 0 {
                /*var new_bs_idx = find_mid(bs.nonterminal, bs.rule_idx, i, bs.left, bs.pivot)*/
                var new_bs_idx = -1
                for (var j = 0; j < BSR.data.size; j++;) {
                    if BSR.data[j].nonterminal == bs.nonterminal && BSR.data[j].rule_idx == bs.rule_idx && BSR.data[j].idx_into_rule == i && BSR.data[j].left == bs.left && BSR.data[j].right == bs.pivot {
                        new_bs_idx = j
                        break
                    }
                }
                bs = BSR.data[new_bs_idx]
            }
        }
        var to_ret = nonterminal_funs[nonterminal][bs.rule_idx].second(nonterminal_funs[nonterminal][bs.rule_idx].first, params.reverse())
        return to_ret
    }
}
obj Pending (Object) {
    var nonterminal: int
    var rule_idx: int
    var idx_into_rule: int
    var left: int
    fun construct(): *Pending {
        return this->construct(0,0,0,0)
    }
    fun construct(nonterminal: int, rule_idx: int, idx_into_rule: int, left: int): *Pending {
        this->nonterminal = nonterminal;
        this->rule_idx = rule_idx;
        this->idx_into_rule = idx_into_rule;
        this->left = left;
        return this
    }
    fun copy_construct(old: *Pending): void {
        this->nonterminal = old->nonterminal;
        this->rule_idx = old->rule_idx;
        this->idx_into_rule = old->idx_into_rule;
        this->left = old->left;
    }
    fun destruct(): void { }
    fun operator=(other:ref Pending):void {
        destruct()
        copy_construct(&other)
    }
    fun operator==(rhs: ref Pending): bool {
        return nonterminal == rhs.nonterminal && rule_idx == rhs.rule_idx && idx_into_rule == rhs.idx_into_rule && left == rhs.left
    }
}
fun pending(nonterminal: int, rule_idx: int, idx_into_rule: int, left: int): Pending {
    var to_ret.construct(nonterminal, rule_idx, idx_into_rule, left): Pending
    return to_ret
}
obj Descriptor (Object) {
    var nonterminal: int
    var rule_idx: int
    var idx_into_rule: int
    var left: int
    var pivot: int
    fun construct(): *Descriptor {
        return this->construct(0,0,0,0,0)
    }
    fun construct(nonterminal: int, rule_idx: int, idx_into_rule: int, left: int, pivot: int): *Descriptor {
        this->nonterminal = nonterminal;
        this->rule_idx = rule_idx;
        this->idx_into_rule = idx_into_rule;
        this->left = left;
        this->pivot = pivot;
        return this
    }
    fun copy_construct(old: *Descriptor): void {
        this->nonterminal = old->nonterminal;
        this->rule_idx = old->rule_idx;
        this->idx_into_rule = old->idx_into_rule;
        this->left = old->left;
        this->pivot = old->pivot;
    }
    fun destruct(): void { }
    fun operator=(other:ref Descriptor):void {
        destruct()
        copy_construct(&other)
    }
    fun operator==(rhs: ref Descriptor): bool {
        return nonterminal == rhs.nonterminal && rule_idx == rhs.rule_idx && idx_into_rule == rhs.idx_into_rule && left == rhs.left && pivot == rhs.pivot
    }
}
fun descriptor(nonterminal: int, rule_idx: int, idx_into_rule: int, left: int, pivot: int): Descriptor {
    var to_ret.construct(nonterminal, rule_idx, idx_into_rule, left, pivot): Descriptor
    return to_ret
}
obj BS (Object) {
    var nonterminal: int
    var rule_idx: int
    var idx_into_rule: int
    var left: int
    var pivot: int
    var right: int
    fun construct(): *BS {
        return this->construct(0,0,0,0,0,0)
    }
    fun construct(nonterminal: int, rule_idx: int, idx_into_rule: int, left: int, pivot: int, right: int): *BS {
        this->nonterminal = nonterminal;
        this->rule_idx = rule_idx;
        this->idx_into_rule = idx_into_rule;
        this->left = left;
        this->pivot = pivot;
        this->right = right;
        return this
    }
    fun copy_construct(old: *BS): void {
        this->nonterminal = old->nonterminal;
        this->rule_idx = old->rule_idx;
        this->idx_into_rule = old->idx_into_rule;
        this->left = old->left;
        this->pivot = old->pivot;
        this->right = old->right;
    }
    fun destruct(): void { }
    fun operator=(other:ref BS):void {
        destruct()
        copy_construct(&other)
    }
    fun to_string(): str {
        return str("nonterminal:") + nonterminal + " rule_idx:" + rule_idx + " idx_into_rule:" + idx_into_rule + " l:" + left + " p:" + pivot + " r:" + right
    }
    fun operator==(rhs: ref BS): bool {
        return nonterminal == rhs.nonterminal && rule_idx == rhs.rule_idx && idx_into_rule == rhs.idx_into_rule && left == rhs.left && pivot == rhs.pivot && right == rhs.right
    }
}
fun bs(nonterminal: int, rule_idx: int, idx_into_rule: int, left: int, pivot: int, right: int): BS {
    var to_ret.construct(nonterminal, rule_idx, idx_into_rule, left, pivot, right): BS
    return to_ret
}
/*fun fungll<T,K>(grammar: ref Grammer<T,K>, start_symbol: *char, input: ref str): set<BS> {*/
    /*return fungll(grammar, str(start_symbol), input)*/
/*}*/
/*fun fungll<T,K>(grammar: ref Grammer<T,K>, start_symbol: str, input: ref str): set<BS> {*/
    /*return fungll(grammar, -1*(grammar.nonterminal_funs.find(start_symbol)+1), input)*/
/*}*/
fun fungll<T,K>(grammar: ref Grammer<T,K>, start_symbol: int, input: ref str): set<BS> {
    var R = descend(grammar, start_symbol, 0)
    var U = set<Descriptor>()
    var G = map<pair<int, int>, set<Pending>>()
    var P = map<pair<int,int>, set<int>>()
    var Y = set<BS>()
    while R.size() != 0 {
        var d = R.pop()
        var it = process(grammar, input, d, G, P)
        var Rp = it.first.first
        var Yp = it.first.second
        var Gp = it.second
        var Pp = it.third

        U.add(d)
        var nextR = R.union(Rp) - U
        R = nextR

        for (var i = 0; i < Gp.keys.size; i++;) {
            if G.contains_key(Gp.keys[i]) {
                G[Gp.keys[i]].add(Gp.values[i])
            } else {
                G[Gp.keys[i]] = Gp.values[i]
            }
        }
        for (var i = 0; i < Pp.keys.size; i++;) {
            if P.contains_key(Pp.keys[i]) {
                P[Pp.keys[i]].add(Pp.values[i])
            } else {
                P[Pp.keys[i]] = Pp.values[i]
            }
        }
        Y += Yp
    }
    return Y
}
fun descend<T,K>(grammar: ref Grammer<T,K>, symbol: int, l: int): set<Descriptor> {
    var to_ret = set<Descriptor>()
    for (var rhs = 0; rhs < grammar.get_nonterminal_rules(symbol).size; rhs++;)
        to_ret.add(descriptor(symbol, rhs, 0, l, l))
    return to_ret
}
fun process<T,K>(grammar: ref Grammer<T,K>, input: ref str, descript: Descriptor, G: ref map<pair<int, int>, set<Pending>>, P: ref map<pair<int,int>, set<int>>): triple<pair<set<Descriptor>, set<BS>>, map<pair<int, int>, set<Pending>>, map<pair<int,int>, set<int>>> {
    // if at end / end is emptystr
    if descript.idx_into_rule == grammar.get_nonterminal_rules(descript.nonterminal)[descript.rule_idx].size {
        return process_e(grammar, descript, G, P)
    } else {
        return process_symbol(grammar, input, descript, G, P)
    }
}
fun process_e<T,K>(grammar: ref Grammer<T,K>, descript: Descriptor, G: ref map<pair<int, int>, set<Pending>>, P: ref map<pair<int,int>, set<int>>): triple<pair<set<Descriptor>, set<BS>>, map<pair<int, int>, set<Pending>>, map<pair<int,int>, set<int>>> {
    var nonterminal: int
    var rule_idx: int
    var left: int
    var pivot: int
    var X = descript.nonterminal
    var l = descript.left;
    var k = descript.pivot;
    var K = G.get_with_default(make_pair(X,l), set<Pending>())
    var it = ascend(l,K,k)
    var R = it.first
    var Y = it.second
    if grammar.get_nonterminal_rules(X)[descript.rule_idx].size == 0 {
        Y.add(bs(X,descript.rule_idx, 0, l, l, l))
    }
    return make_triple(make_pair(R,Y), map<pair<int, int>, set<Pending>>(), map(make_pair(X,l), set(k)))
}
fun process_symbol<T,K>(grammar: ref Grammer<T,K>, input: ref str, descript: Descriptor, G: ref map<pair<int, int>, set<Pending>>, P: ref map<pair<int,int>, set<int>>): triple<pair<set<Descriptor>, set<BS>>, map<pair<int, int>, set<Pending>>, map<pair<int,int>, set<int>>> {
    var s = grammar.get_nonterminal_rules(descript.nonterminal)[descript.rule_idx][descript.idx_into_rule]
    var k = descript.pivot
    var R = P.get_with_default(make_pair(s,k), set<int>())
    var Gp = map(make_pair(s,k), set(pending(descript.nonterminal, descript.rule_idx, descript.idx_into_rule+1, descript.left)))
    if grammar.is_terminal(s) {
        return make_triple(matc(grammar,input,descript), map<pair<int,int>, set<Pending>>(), map<pair<int,int>, set<int>>())
    } else if R.size() == 0 { // s in N
        return make_triple(make_pair(descend(grammar,s,k), set<BS>()), Gp, map<pair<int,int>, set<int>>())
    } else { // s in N and R != set()
        return make_triple(skip(k,pending(descript.nonterminal, descript.rule_idx, descript.idx_into_rule+1, descript.left), R), Gp, map<pair<int,int>, set<int>>())
    }
}
fun matc<T,K>(grammar: ref Grammer<T,K>, input: ref str, descript: Descriptor): pair<set<Descriptor>, set<BS>> {
    /*println("trying to match " + grammar.to_string(grammar.get_nonterminal_rules(descript.nonterminal)[descript.rule_idx][descript.idx_into_rule]))*/
    var match_length = grammar.match_terminal(grammar.get_nonterminal_rules(descript.nonterminal)[descript.rule_idx][descript.idx_into_rule], input, descript.pivot)
    if match_length > 0 {
        /*println("matched " + grammar.to_string(grammar.get_nonterminal_rules(descript.nonterminal)[descript.rule_idx][descript.idx_into_rule]))*/
        return make_pair(set(descriptor(descript.nonterminal, descript.rule_idx, descript.idx_into_rule+1, descript.left, descript.pivot+match_length)), set(bs(descript.nonterminal, descript.rule_idx, descript.idx_into_rule+1, descript.left, descript.pivot, descript.pivot+match_length)))
    } else {
        return make_pair(set<Descriptor>(), set<BS>())
    }
}
fun skip(k: int, c: Pending, R: ref set<int>): pair<set<Descriptor>, set<BS>> { return nmatch(k, set(c), R); }
fun ascend(k:int, K: ref set<Pending>, r: int): pair<set<Descriptor>, set<BS>> { return nmatch(k, K, set(r)); }
fun nmatch(k:int, K: ref set<Pending>, R: ref set<int>): pair<set<Descriptor>, set<BS>> {
    var Rp = set<Descriptor>()
    var Y = set<BS>()
    for (var i = 0; i < K.data.size; i++;) {
        var pending = K.data[i]
        for (var j = 0; j < R.data.size; j++;) {
            var r = R.data[j]
            Rp.add(descriptor(pending.nonterminal, pending.rule_idx, pending.idx_into_rule, pending.left, r))
            Y.add(bs(pending.nonterminal, pending.rule_idx, pending.idx_into_rule, pending.left, k, r))
        }
    }
    return make_pair(Rp,Y)
}
/*fun main(argc: int, argv: **char): int {*/
    /*var grammar.construct(): Grammer<int>*/
    /*var Number = grammar.add_new_nonterminal("Number", vec(grammar.add_terminal("[0-9]+", fun(input: ref str, l: int, r: int): int { return string_to_num<int>(input.slice(l,r)); })), fun(i: ref vec<int>): int { return i[0]; })*/

    /*var mult = grammar.add_terminal("\\*", fun(input: ref str, l: int, r: int): int { return 1; })*/
    /*var Factor = grammar.add_new_nonterminal("Factor", vec(Number), fun(i: ref vec<int>): int { return i[0]; })*/
    /*grammar.add_to_nonterminal(Factor, vec(Factor, mult, Number), fun(i: ref vec<int>): int { return i[0]*i[2]; })*/

    /*var add = grammar.add_terminal("\\+", fun(input: ref str, l: int, r: int): int { return 1; })*/
    /*var Term = grammar.add_new_nonterminal("Term", vec(Factor), fun(i: ref vec<int>): int { return i[0]; })*/
    /*grammar.add_to_nonterminal(Term, vec(Term, add, Factor), fun(i: ref vec<int>): int { return i[0]+i[2]; })*/

    /*grammar.set_start_symbol(Term)*/

    /*var input = str("1+23*44")*/
    /*var BSR = fungll(grammar, input)*/


    /*println(str("length of BSR is: ") + BSR.size())*/
    /*for (var i = 0; i < BSR.data.size; i++;) {*/
        /*var BS = BSR.data[i]*/
        /*println(str() + i + ": " + grammar.to_string(BSR.data[i]))*/
    /*}*/

    /*var res = grammar.eval_BSR(input, BSR)*/
    /*println(str("result of grammar.eval_BSR(fungll(grammar, ") + input + ")) = " + res)*/

    /*return 0*/
/*}*/