#ifndef COMPILER_PARSE_TABLE_H_
#define COMPILER_PARSE_TABLE_H_

#include <map>
#include <set>
#include <utility>
#include <vector>
#include "compiler/lex_table.h"
#include "compiler/rules/symbol.h"

namespace tree_sitter {
    typedef enum {
        ParseActionTypeError,
        ParseActionTypeAccept,
        ParseActionTypeShift,
        ParseActionTypeReduce,
    } ParseActionType;

    class ParseAction {
        ParseAction(ParseActionType type,
                    size_t state_index,
                    rules::Symbol symbol,
                    size_t consumed_symbol_count);
    public:
        static ParseAction Accept();
        static ParseAction Error();
        static ParseAction Shift(size_t state_index);
        static ParseAction Reduce(rules::Symbol symbol, size_t consumed_symbol_count);
        bool operator==(const ParseAction &action) const;

        ParseActionType type;
        rules::Symbol symbol;
        size_t state_index;
        size_t consumed_symbol_count;
    };

    std::ostream& operator<<(std::ostream &stream, const ParseAction &item);
}

namespace std {
    template<>
    struct hash<tree_sitter::ParseAction> {
        size_t operator()(const tree_sitter::ParseAction &action) const {
            return (
                    hash<int>()(action.type) ^
                    hash<tree_sitter::rules::Symbol>()(action.symbol) ^
                    hash<size_t>()(action.state_index) ^
                    hash<size_t>()(action.consumed_symbol_count));
        }
    };
}

namespace tree_sitter {
    class ParseState {
    public:
        ParseState();
        std::map<rules::Symbol, ParseAction> actions;
        std::set<rules::Symbol> expected_inputs() const;
        LexStateId lex_state_id;
    };

    typedef uint64_t ParseStateId;

    std::ostream& operator<<(std::ostream &stream, const ParseState &state);

    class ParseTable {
    public:
        uint64_t add_state();
        void add_action(ParseStateId state_id, rules::Symbol symbol, ParseAction action);

        std::vector<ParseState> states;
        std::set<rules::Symbol> symbols;
    };
}

#endif  // COMPILER_PARSE_TABLE_H_