#include "libsyntax.h"
#include "ast_basic.h"

using namespace lib_syntax;
using namespace std;
using namespace lib_token;
using namespace ast_basic;

TokenMatch::TokenMatch(shared_ptr<const TokenDefine> define) : define_peer(define) {}

QList<std::shared_ptr<const BaseRule>> TokenMatch::children() const { return QList<std::shared_ptr<const BaseRule>>(); }

std::tuple<BaseRule::MatchResult, uint, std::shared_ptr<const Token>> TokenMatch::match(std::shared_ptr<const Token> remains_head) const {
	QString token_seqs = this->token_present();
	if (remains_head && remains_head->define()->name() == define_peer->name())
		return std::make_tuple(MatchResult::Success, 1, remains_head->nextToken());

	return std::make_tuple(MatchResult::Fail, 0, nullptr);
	//    auto mis_match = define_peer->name();
	//    auto real_match = stream.first()->define()->name();
}
// std::tuple<std::shared_ptr<const ast_basic::Expression>, std::shared_ptr<const lib_token::Token>>
std::tuple<std::shared_ptr<const Expression>, std::shared_ptr<const Token>> TokenMatch::parse(std::shared_ptr<ParseContext> rt_inst, std::shared_ptr<const Token> head) const {
	if (!head)
		throw std::make_shared<InputTerminal>();

	if (head->define()->name() == define_peer->name()) {
		rt_inst->currentInst()->addToken(head);
		return std::make_tuple(nullptr, head->nextToken());
	}

	throw std::make_shared<MismatchException>(head);
}

QString TokenMatch::token_present() const {
	return QString(u8"<%1>").arg(this->define_peer->name());
}

Rept::Rept(std::shared_ptr<const BaseRule> rule, int min, int max) : rule_peer(rule), min_match(min), max_match(max) {}

QList<std::shared_ptr<const BaseRule>> Rept::children() const { return QList<std::shared_ptr<const BaseRule>>() << rule_peer; }

std::tuple<BaseRule::MatchResult, uint, std::shared_ptr<const Token>> Rept::match(std::shared_ptr<const Token> list_head) const {
	auto token_offset = 0;
	QString token_seqs = this->token_present();
	auto temp_head = list_head;

	// min-match
	for (auto idx = 0; idx < min_match; ++idx) {
		auto result = rule_peer->match(temp_head);
		token_offset += std::get<1>(result);
		temp_head = std::get<2>(result);

		if (std::get<0>(result) != MatchResult::Success) {
			return std::make_tuple(token_offset ? MatchResult::Part : MatchResult::Fail, token_offset, temp_head);
		}
	}

	// max-match
	for (auto idx = min_match; idx < max_match; ++idx) {
		auto result = rule_peer->match(temp_head);

		switch (std::get<0>(result)) {
		case MatchResult::Fail:
		case MatchResult::Part:
			return std::make_tuple(MatchResult::Success, token_offset, temp_head);
		default:
			temp_head = std::get<2>(result);
			token_offset += std::get<1>(result);
			break;
		}
	}

	return std::make_tuple(MatchResult::Success, token_offset, temp_head);
}

std::tuple<std::shared_ptr<const Expression>, std::shared_ptr<const Token>> Rept::parse(std::shared_ptr<ParseContext> rt_inst, std::shared_ptr<const Token> head) const {
	auto temp_head = head;

	// min-match
	for (auto idx = 0; idx < min_match; ++idx) {
		auto result_gen = rule_peer->parse(rt_inst, temp_head);
		if (std::get<0>(result_gen))
			rt_inst->currentInst()->addChild(std::get<0>(result_gen));

		temp_head = std::get<1>(result_gen);
	}

	// max-match
	for (auto idx = min_match; idx < max_match; ++idx) {
		try {
			auto result_gen = rule_peer->parse(rt_inst, temp_head);
			if (std::get<0>(result_gen))
				rt_inst->currentInst()->addChild(std::get<0>(result_gen));

			temp_head = std::get<1>(result_gen);
		}
		catch (std::shared_ptr<MismatchException> ex) {
			return std::make_tuple(nullptr, temp_head);
		}
		catch (std::shared_ptr<InputTerminal> ex) {
			return std::make_tuple(nullptr, temp_head);
		}
	}

	return std::make_tuple(nullptr, temp_head);
}

QString Rept::token_present() const
{
	return u8"(" + this->rule_peer->token_present() + QString(u8"{%1, %2}").arg(min_match).arg(max_match) + u8")";
}

Seqs::Seqs(const QList<std::shared_ptr<const BaseRule>> mbrs) : mbrs_store(mbrs) {}

QList<std::shared_ptr<const BaseRule>> Seqs::children() const { return mbrs_store; }

std::tuple<BaseRule::MatchResult, uint, std::shared_ptr<const Token>> Seqs::match(std::shared_ptr<const Token> list_head) const {
	auto token_offset = 0;
	QString token_seqs = this->token_present();
	auto temp_head = list_head;

	for (auto& r : mbrs_store) {
		auto v_token_seqs = r->token_present();
		auto result = r->match(list_head);
		token_offset += std::get<1>(result);
		temp_head = std::get<2>(result);

		switch (std::get<0>(result)) {
		case MatchResult::Fail:
		case MatchResult::Part:
			return std::make_tuple(token_offset ? MatchResult::Part : MatchResult::Fail, token_offset, temp_head);
		default:
			break;
		}
	}

	return std::make_tuple(MatchResult::Success, token_offset, temp_head);
}

std::tuple<std::shared_ptr<const Expression>, std::shared_ptr<const Token>> Seqs::parse(std::shared_ptr<ParseContext> rt_inst, std::shared_ptr<const Token> head) const {
	auto temp_head = head;

	for (auto& r : mbrs_store) {
		auto rst_gene = r->parse(rt_inst, temp_head);
		temp_head = std::get<1>(rst_gene);

		if (std::get<0>(rst_gene))
			rt_inst->currentInst()->addChild(std::get<0>(rst_gene));
	}

	return std::make_tuple(nullptr, temp_head);
}

QString Seqs::token_present() const
{
	QString content;
	for (auto& it : children())
		content += it->token_present();
	return QString(u8"(%1)").arg(content);
}

std::tuple<BaseRule::MatchResult, uint, std::shared_ptr<const BaseRule>, std::shared_ptr<const Token>>
Any::rule_select(std::shared_ptr<const Token> head) const {
	QString token_seqs = this->token_present();
	std::tuple<MatchResult, uint, std::shared_ptr<const BaseRule>, std::shared_ptr<const Token>> temp = std::make_tuple(MatchResult::Fail, 0, nullptr, nullptr);

	for (auto& r : mbrs_store) {
		auto mbr_seqs = r->token_present();
		auto result = r->match(head);
		if (std::get<0>(result) == MatchResult::Success)
			return std::make_tuple(std::get<0>(result), std::get<1>(result), r, std::get<2>(result));

		else if (std::get<0>(result) == MatchResult::Part) {
			if (std::get<0>(temp) == MatchResult::Fail || std::get<1>(result) > std::get<1>(temp))
				temp = std::make_tuple(MatchResult::Part, std::get<1>(result), r, std::get<2>(result));
			else
				temp = std::make_tuple(MatchResult::Part, std::get<1>(temp), std::get<2>(temp), std::get<3>(temp));
		}

		else if (std::get<0>(temp) == MatchResult::Fail) {
			if (!std::get<2>(temp) || std::get<1>(result) > std::get<1>(temp))
				temp = std::make_tuple(MatchResult::Fail, std::get<1>(result), r, std::get<2>(result));
			else
				temp = std::make_tuple(MatchResult::Fail, std::get<1>(temp), std::get<2>(temp), std::get<3>(temp));
		}
	}

	return temp;
}

Any::Any(const QList<std::shared_ptr<const BaseRule>> mbrs) : mbrs_store(mbrs) {}

QList<std::shared_ptr<const BaseRule>> Any::children() const { return mbrs_store; }

std::tuple<BaseRule::MatchResult, uint, std::shared_ptr<const Token>> Any::match(std::shared_ptr<const Token> list_head) const {
	auto item = rule_select(list_head);
	return std::make_tuple(std::get<0>(item), std::get<1>(item), std::get<3>(item));
}

std::tuple<std::shared_ptr<const Expression>, std::shared_ptr<const Token>> Any::parse(std::shared_ptr<ParseContext> rt_inst, std::shared_ptr<const Token> head) const {
	std::function<int(std::shared_ptr<const Token>, std::shared_ptr<const Token>)> measure_span =
		[&](std::shared_ptr<const Token> anchor, std::shared_ptr<const Token> head)->int {
		if (anchor == head)
			return 1;
		return measure_span(anchor, head->nextToken()) + 1;
	};

	std::tuple<std::shared_ptr<const BaseRule>, int> temp_result = std::make_tuple(mbrs_store.first(), 0);
	for (auto& fork : mbrs_store) {
		try {
			auto gen = fork->parse(rt_inst, head);

			// 遇到成功的直接返回解析结果
			if (std::get<0>(gen))
				rt_inst->currentInst()->addChild(std::get<0>(gen));
			return std::make_tuple(nullptr, std::get<1>(gen));
		}
		// 语法错误的会进行比较
		catch (std::shared_ptr<MismatchException> ex) {
			auto current_span = measure_span(ex->targetToken(), head);

			if (current_span > std::get<1>(temp_result))
				temp_result = std::make_tuple(fork, current_span);
		}
	}

	// 分析最匹配的分支
	return std::get<0>(temp_result)->parse(rt_inst, head);
}

QString Any::token_present() const
{
	QString members_content;
	for (auto& it : children()) {
		members_content += it->token_present() + u8"|";
	}
	return u8"(" + members_content.mid(0, members_content.size() - 1) + u8")";
}


SyntaxException::SyntaxException(const QString& message) { this->msg_store = message; }

QString SyntaxException::message() const { return msg_store; }

ExpressionRule::ExpressionRule(const QString& rule_name, int expr_mark) : name_store(rule_name) {
	this->filter_proc = [](const TokenSeqs& seqs) { return seqs; };
	this->mark_store = expr_mark;
}

std::shared_ptr<const ExpressionRule> ExpressionRule::reloadRule(std::function<TokenSeqs(const TokenSeqs&)> filter, std::shared_ptr<const BaseRule> rule) {
	auto ninst = makeCopy();
	ninst->child_store = rule;
	ninst->filter_proc = filter;
	return ninst;
}

QString ExpressionRule::name() const { return name_store; }

int ExpressionRule::typeMark() const { return this->mark_store; }

QList<std::shared_ptr<const BaseRule>> ExpressionRule::children() const {
	return QList<std::shared_ptr<const BaseRule>>() << this->child_store;
}

std::tuple<BaseRule::MatchResult, uint, std::shared_ptr<const Token>> ExpressionRule::match(std::shared_ptr<const Token> list_head) const {
	return child_store->match(list_head);
}

std::tuple<std::shared_ptr<const Expression>, std::shared_ptr<const Token>> ExpressionRule::parse(std::shared_ptr<ParseContext> rt_inst, std::shared_ptr<const Token> head) const {
	std::shared_ptr<Expression> elm_ast = this->newEmptyInstance();

	rt_inst->pushExpressionRule(this->shared_from_this());
	rt_inst->pushInst(elm_ast);

	try {
		auto rstg = child_store->parse(rt_inst, head);

		auto tokens_decl = this->filter_proc(elm_ast->tokens());
		elm_ast->tokensReset(tokens_decl);

		rt_inst->popInst();
		rt_inst->popExpressionRule();
		return std::make_tuple(elm_ast, std::get<1>(rstg));
	}
	catch (...) {
		rt_inst->popInst();
		rt_inst->popExpressionRule();
		throw;
	}
}

QString ExpressionRule::token_present() const {
	return QString(u8"(%1)").arg(child_store->token_present());
}

MismatchException::MismatchException(std::shared_ptr<const lib_token::Token> inst) :SyntaxException(
	QString(u8"Syntax[0x00001]语法匹配错误，不能识别token：%1<%2,%3>").arg(inst->content()).arg(inst->row()).arg(inst->column())), target(inst) {}

std::shared_ptr<const Token>MismatchException::targetToken() const {
	return this->target;
}

InputTerminal::InputTerminal() :SyntaxException(u8"Syntax[0x0000]token流提前终止") {}