#pragma once

#include "libsyntax_global.h"
#include "libtokens.h"
#include "tokens_impl.h"
#include <memory>
#include <QtCore/QList>
#include <QtCore/QDebug>
#include <tuple>
#include <functional>
#include "ast_basic.h"

namespace lib_syntax {
	/**
	 * @brief 语法异常
	 */
	class  LIBSYNTAX_EXPORT SyntaxException {
	private:
		QString msg_store;

	public:
		SyntaxException(const QString& message);
		virtual ~SyntaxException() = default;

		virtual QString message() const;
	};





	// 基础语法解析接口 ====================================================================================
	/**
	 * @brief 解析上下文接口
	 */
	class LIBSYNTAX_EXPORT MatchCursor {
	public:
		class ErrsPack {
		public:
			ErrsPack();
			ErrsPack(const ErrsPack& other);

			void addError(const QString& msg);
			QList<QString> errors() const;
			uint64_t errorCount() const;

		private:
			QList<QString> _error_collection;
		};

		MatchCursor(const QString& path);
		MatchCursor(std::shared_ptr<const MatchCursor> other_ptr);
		virtual ~MatchCursor() = default;

		virtual std::shared_ptr<const MatchCursor> previous() const;
		virtual QString filePath() const;
		virtual QString parseSyntax() const;

		virtual void enterExprs();
		virtual void logExprsError(const QString& msg);
		virtual void quitExprs();
		virtual int exprsErrorCount() const;
		virtual int totalErrorCount() const;
		virtual QList<QString> totalErrors() const;

		virtual bool parseFailure() const;
		virtual void setFailure(bool mark = true);
		virtual bool parseComplete() const;
		virtual void setComplete(bool mark = true);

		virtual void setCurrent(std::shared_ptr<const lib_token::IActionToken> t, std::shared_ptr<const lib_words::IPrimitiveWord> remains);
		virtual std::shared_ptr<const lib_token::IActionToken> token() const;
		virtual std::shared_ptr<const lib_words::IPrimitiveWord> words() const;

	private:
		QString _file_path;
		std::shared_ptr<const MatchCursor> _prev_cursor = nullptr;
		bool _parse_stop_with_errors = false, _parse_complete = false;

		QList<QString> _total_errors; // 所有解析错误
		QList<std::shared_ptr<ErrsPack>> _exprs_errors; // 当前表达式解析错误
		std::shared_ptr<const lib_token::IActionToken> _current_token = nullptr;		// 当前Token
		std::shared_ptr<const lib_words::IPrimitiveWord> _remains_word = nullptr;		// 剩余词语
	};

	/**
	 * @brief 基础语法匹配规则接口
	 */
	class IBasicRule {
	public:
		/**
		 * @brief 子规则
		 * @return
		 */
		virtual QList<std::shared_ptr<const IBasicRule>> children() const = 0;

		/**
		 * 返回匹配语法规则的词法序列表达
		 *
		 * \return 词法表达序列
		 */
		virtual QString present() const = 0;

		/**
		 * @brief 解析
		 * @param cursor 解析游标
		 * @param out 解析结束的分支存储集合
		 * @return 返回结果<匹配分支>
		 */
		virtual QList<std::shared_ptr<const MatchCursor>> parse(std::shared_ptr<const MatchCursor> cursor) const = 0;
	};

	// 组合语法实体解析 =====================================================================================
	/**
	 * @brief 语法规则或匹配
	 */
	class LIBSYNTAX_EXPORT __anyone_impl : public IBasicRule, public std::enable_shared_from_this<__anyone_impl> {
	private:
		QList<std::shared_ptr<const IBasicRule>> mbrs_store;

	public:
		__anyone_impl(const QList<std::shared_ptr<const IBasicRule>> mbrs);

		// IBasicRule interface
	public:
		virtual QList<std::shared_ptr<const IBasicRule>> children() const override;
		virtual QList<std::shared_ptr<const MatchCursor>> parse(std::shared_ptr<const MatchCursor> cursor) const override;
		virtual QString present() const override;
	};

	/**
	 * @brief 语法规则序列匹配
	 */
	class LIBSYNTAX_EXPORT __sequence_impl : public IBasicRule, public std::enable_shared_from_this<__sequence_impl> {
	private:
		QList<std::shared_ptr<const IBasicRule>> mbrs_store;

	public:
		__sequence_impl(const QList<std::shared_ptr<const IBasicRule>> mbrs);

		// IBasicRule interface
	public:
		virtual QList<std::shared_ptr<const IBasicRule>> children() const override;
		virtual QList<std::shared_ptr<const MatchCursor>> parse(std::shared_ptr<const MatchCursor> cursor) const override;
		virtual QString present() const override;
	};

	/**
	 * @brief 语法规则重复匹配
	 */
	class LIBSYNTAX_EXPORT __repeat_impl : public IBasicRule, public std::enable_shared_from_this<__repeat_impl> {
	private:
		std::shared_ptr<const IBasicRule> rule_peer;
		int min_match, max_match;

	public:
		__repeat_impl(std::shared_ptr<const IBasicRule> rule, int min, int max);

		// IBasicRule interface
	public:
		virtual QList<std::shared_ptr<const IBasicRule>> children() const override;
		virtual QList<std::shared_ptr<const MatchCursor>> parse(std::shared_ptr<const MatchCursor> cursor) const override;
		virtual QString present() const override;
	};

	/**
	 * @brief 对应语法表达式解析规则
	 */
	class LIBSYNTAX_EXPORT ExprRule : public IBasicRule, public std::enable_shared_from_this<ExprRule> {
	public:
		ExprRule(const QString& rule_name, int expr_mark);

		virtual QString name() const;
		virtual int typeMark() const;

	protected:
		virtual QList<std::shared_ptr<const MatchCursor>> expr_rule_parse(std::shared_ptr<const MatchCursor> cursor) const = 0;

	private:
		QString name_store;
		int mark_store;
	};



	/**
	 * @brief token匹配
	 */
	template<typename ELEM, lib_token::TokenProc<ELEM> XProc = nullptr>
		requires std::derived_from<ELEM, ast_basic::IExprInstance>
	class __token_match_impl : public IBasicRule, public std::enable_shared_from_this<__token_match_impl<ELEM, XProc>> {
	private:
		std::shared_ptr<const lib_token::ITokenProcess> _define_peers;

	public:
		__token_match_impl(std::shared_ptr<const lib_token::ITokenProcess> define) : _define_peers(define) { }

		// IBasicRule interface
	public:
		virtual QString present() const override {
			return QString("%1").arg(this->_define_peers->reviseWords());
		}
		virtual QList<std::shared_ptr<const MatchCursor>> parse(std::shared_ptr<const MatchCursor> current) const override {
			// 如果提前结束，记录错误并返回
			if (!current->words()) {
				// 只有在表达式的起始点遇到nullptr，才是正常结束。
				if (current->token()->tokenType() != lib_token::IActionToken::Type::ElementBegin) {
					auto ncurs = std::make_shared<MatchCursor>(current);
					ncurs->logExprsError(QString("SyntaxError[0x00001]输入错误，程序提前结束：%1。").arg(current->filePath()));
					ncurs->setFailure();
					return QList<std::shared_ptr<const MatchCursor>>() << ncurs;
				}

				while (current->token()->tokenType() == lib_token::IActionToken::Type::ElementBegin)
					current = current->previous();

				auto ncurs = std::make_shared<MatchCursor>(current);
				ncurs->setComplete();
				return QList<std::shared_ptr<const MatchCursor>>() << ncurs;
			}

			auto w_this = current->words();
			auto t_this = current->token();
			auto match_result = _define_peers->analysis(w_this);
			// 解析成功
			if (std::get<0>(match_result)) {
				auto chain = std::make_shared<lib_token::ActionToken<ELEM, XProc>>(std::get<0>(match_result), t_this);
				auto remains = w_this->nextWord();
				if (std::get<1>(match_result)) {
					remains = std::make_shared<lib_words::WordImpl>(std::get<1>(match_result), remains);
				}

				auto clone_ins = std::make_shared<MatchCursor>(current);
				clone_ins->setCurrent(chain, remains);
				return QList<std::shared_ptr<const MatchCursor>>() << clone_ins;
			}
			else {
				QList<std::shared_ptr<const MatchCursor>> retvals;
				// 少一个
				auto short_one = std::make_shared<MatchCursor>(current);
				short_one->logExprsError(QString("SyntaxError[0x00002]语法匹配错误，缺失\"%1\"<row:%2,col:%3,file<%4>>")
					.arg(this->_define_peers->reviseWords())
					.arg(w_this->row()).arg(w_this->column()).arg(w_this->file()));
				retvals << short_one;

				// 错一个
				auto error_one = std::make_shared<MatchCursor>(current);
				error_one->logExprsError(QString("SyntaxError[0x00003]语法匹配错误，请修正\"%1\"<row:%2,col:%3,file<%4>>")
					.arg(w_this->content()).arg(w_this->row()).arg(w_this->column()).arg(w_this->file()));
				auto tkins = std::make_shared<lib_token::TokenContent>(
					w_this->row(), w_this->column(), w_this->position(),
					QString("%2_%1").arg((uint64_t) error_one.get()).arg(this->_define_peers->reviseWords()),
					w_this->file(), this->_define_peers);
				auto tkchain = std::make_shared<lib_token::ActionToken<ELEM, XProc>>(tkins, t_this);
				error_one->setCurrent(tkchain, w_this->nextWord());
				retvals << error_one;

				// 多一个
				auto nx_word = w_this->nextWord();
				if (nx_word) {
					auto nx_result = this->_define_peers->analysis(nx_word);
					if (std::get<0>(nx_result)) {
						auto chain = std::make_shared<lib_token::ActionToken<ELEM, XProc>>(std::get<0>(nx_result), t_this);
						auto remains = nx_word->nextWord();
						if (std::get<1>(nx_result)) {
							remains = std::make_shared<lib_words::WordImpl>(std::get<1>(nx_result), remains);
						}

						auto clone_ins = std::make_shared<MatchCursor>(current);
						clone_ins->logExprsError(QString("SyntaxError[0x00004]语法匹配错误，请删除\"%1\"<row:%2,col:%3,file<%4>>")
							.arg(w_this->content()).arg(w_this->row()).arg(w_this->column()).arg(w_this->file()));
						clone_ins->setCurrent(chain, remains);
						retvals << clone_ins;
					}
				}

				return retvals;
			}
		}
		virtual QList<std::shared_ptr<const IBasicRule>> children() const override {
			return QList<std::shared_ptr<const IBasicRule>>();
		}
	};

	/**
	 * @brief 基础模板化语法元素解析规则.
	 */
	template<class ExprType, int mark, typename R>
		requires std::derived_from<ExprType, ast_basic::IExprInstance>&& std::derived_from<R, lib_syntax::IBasicRule>
	class ElementRule : public ExprRule {
	public:
		ElementRule(const QString& rule_name)
			:ExprRule(rule_name, mark), _children_store(std::make_shared<R>()) { }

		virtual QList<std::shared_ptr<const IBasicRule>> children() const {
			return QList<std::shared_ptr<const IBasicRule>>() << this->_children_store;
		}

		virtual QString present() const {
			return this->_children_store->present();
		}

		virtual QList<std::shared_ptr<const MatchCursor>> parse(std::shared_ptr<const MatchCursor> cursor) const override {
			// 提前结束，直接返回
			if (cursor->parseFailure() && cursor->parseComplete())
				return QList<std::shared_ptr<const MatchCursor>>() << cursor;

			auto syntax = present();

			auto t_this = cursor->token();
			auto w_this = cursor->words();
			// 起始Token打点
			auto split_begin = std::make_shared<lib_token::ExprBeginToken<ExprType>>(shared_from_this(), t_this);

			auto ncursor = std::make_shared<MatchCursor>(cursor);
			ncursor->setCurrent(split_begin, w_this);
			ncursor->enterExprs();

			// 表达式语法解析
			auto nbranch = this->expr_rule_parse(ncursor);

			// 语法完全匹配的分支
			decltype(nbranch) branch_procs;
			std::copy_if(nbranch.begin(), nbranch.end(),
				std::back_inserter(branch_procs),
				[&](std::shared_ptr<const MatchCursor> ins) {
					return ins->totalErrorCount() == cursor->totalErrorCount() || ins->parseComplete();
				});

			// 语法修正后能匹配的分支
			if (!branch_procs.size()) {
				std::copy_if(nbranch.begin(), nbranch.end(),
					std::back_inserter(branch_procs),
					[](std::shared_ptr<const MatchCursor> ins) { return !ins->parseFailure(); });
			}

			if (!branch_procs.size())
				branch_procs = nbranch;


			decltype(nbranch) results_fnl;
			for (auto curs : branch_procs) {
				if (curs->parseFailure())
					results_fnl.append(curs);
				else {
					auto t_end = curs->token();
					auto w_end = curs->words();

					auto ecursor = std::make_shared<MatchCursor>(curs);
					ecursor->quitExprs();

					auto split_end = std::make_shared<lib_token::ExprEndToken<ExprType>>(split_begin, t_end);
					ecursor->setCurrent(split_end, w_end);
					results_fnl.append(ecursor);
				}
			}

			return results_fnl;
		}

	protected:
		std::shared_ptr<const IBasicRule> _children_store;
	};
} // namespace lib_syntax