/*
 * Copyright 2015 WebAssembly Community Group participants
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#include "parser.h"

namespace cashew {

// common strings

IString TOPLEVEL("toplevel"),
        DEFUN("defun"),
        BLOCK("block"),
        STAT("stat"),
        ASSIGN("assign"),
        NAME("name"),
        VAR("var"),
        CONST("const"),
        CONDITIONAL("conditional"),
        BINARY("binary"),
        RETURN("return"),
        IF("if"),
        ELSE("else"),
        WHILE("while"),
        DO("do"),
        FOR("for"),
        SEQ("seq"),
        SUB("sub"),
        CALL("call"),
        NUM("num"),
        LABEL("label"),
        BREAK("break"),
        CONTINUE("continue"),
        SWITCH("switch"),
        STRING("string"),
        INF("inf"),
        NaN("nan"),
        TEMP_RET0("tempRet0"),
        GET_TEMP_RET0("getTempRet0"),
        LLVM_CTTZ_I32("_llvm_cttz_i32"),
        UDIVMODDI4("___udivmoddi4"),
        UNARY_PREFIX("unary-prefix"),
        UNARY_POSTFIX("unary-postfix"),
        MATH_FROUND("Math_fround"),
        INT64("i64"),
        INT64_CONST("i64_const"),
        SIMD_FLOAT32X4("SIMD_Float32x4"),
        SIMD_FLOAT64X2("SIMD_Float64x2"),
        SIMD_INT8X16("SIMD_Int8x16"),
        SIMD_INT16X8("SIMD_Int16x8"),
        SIMD_INT32X4("SIMD_Int32x4"),
        PLUS("+"),
        MINUS("-"),
        OR("|"),
        AND("&"),
        XOR("^"),
        L_NOT("!"),
        B_NOT("~"),
        LT("<"),
        GE(">="),
        LE("<="),
        GT(">"),
        EQ("=="),
        NE("!="),
        DIV("/"),
        MOD("%"),
        MUL("*"),
        RSHIFT(">>"),
        LSHIFT("<<"),
        TRSHIFT(">>>"),
        TEMP_DOUBLE_PTR("tempDoublePtr"),
        HEAP8("HEAP8"),
        HEAP16("HEAP16"),
        HEAP32("HEAP32"),
        HEAPF32("HEAPF32"),
        HEAPU8("HEAPU8"),
        HEAPU16("HEAPU16"),
        HEAPU32("HEAPU32"),
        HEAPF64("HEAPF64"),
        F0("f0"),
        EMPTY(""),
        FUNCTION("function"),
        OPEN_PAREN("("),
        OPEN_BRACE("["),
        OPEN_CURLY("{"),
        CLOSE_CURLY("}"),
        COMMA(","),
        QUESTION("?"),
        COLON(":"),
        CASE("case"),
        DEFAULT("default"),
        DOT("dot"),
        PERIOD("."),
        NEW("new"),
        ARRAY("array"),
        OBJECT("object"),
        THROW("throw"),
        SET("=");

IStringSet keywords("var const function if else do while for break continue return switch case default throw try catch finally true false null new");

const char *OPERATOR_INITS = "+-*/%<>&^|~=!,?:.",
           *SEPARATORS = "([;{}";

int MAX_OPERATOR_SIZE = 3;

std::vector<OperatorClass> operatorClasses;

static std::vector<std::unordered_map<IString, int>> precedences; // op, type => prec

struct Init {
  Init() {
    // operators, rtl, type
    operatorClasses.emplace_back(".",         false, OperatorClass::Binary);
    operatorClasses.emplace_back("! ~ + -",   true,  OperatorClass::Prefix);
    operatorClasses.emplace_back("* / %",     false, OperatorClass::Binary);
    operatorClasses.emplace_back("+ -",       false, OperatorClass::Binary);
    operatorClasses.emplace_back("<< >> >>>", false, OperatorClass::Binary);
    operatorClasses.emplace_back("< <= > >=", false, OperatorClass::Binary);
    operatorClasses.emplace_back("== !=",     false, OperatorClass::Binary);
    operatorClasses.emplace_back("&",         false, OperatorClass::Binary);
    operatorClasses.emplace_back("^",         false, OperatorClass::Binary);
    operatorClasses.emplace_back("|",         false, OperatorClass::Binary);
    operatorClasses.emplace_back("? :",       true,  OperatorClass::Tertiary);
    operatorClasses.emplace_back("=",         true,  OperatorClass::Binary);
    operatorClasses.emplace_back(",",         true,  OperatorClass::Binary);

    precedences.resize(OperatorClass::Tertiary + 1);

    for (size_t prec = 0; prec < operatorClasses.size(); prec++) {
      for (auto curr : operatorClasses[prec].ops) {
        precedences[operatorClasses[prec].type][curr] = prec;
      }
    }
  }
};

Init init;

int OperatorClass::getPrecedence(Type type, IString op) {
  return precedences[type][op];
}

bool OperatorClass::getRtl(int prec) {
  return operatorClasses[prec].rtl;
}

bool isIdentInit(char x) { return (x >= 'a' && x <= 'z') || (x >= 'A' && x <= 'Z') || x == '_' || x == '$'; }
bool isIdentPart(char x) { return isIdentInit(x) || (x >= '0' && x <= '9'); }

} // namespace cashew