/*
 * Copyright 1999-2017 Alibaba Group Holding Ltd.
 *
 * 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.
 */
package com.alibaba.druid.sql.ast.expr;

/**
 * 二元操作符
 *
 * @author wenshao 2011-5-20 下午12:32:02
 */
public enum SQLBinaryOperator {
    Union("UNION", 0),
    COLLATE("COLLATE", 20),
    BitwiseXor("^", 50),
    BitwiseXorEQ("^=", 110),

    Multiply("*", 60),
    Divide("/", 60),
    DIV("DIV", 60), // mysql integer division
    Modulus("%", 60),
    Mod("MOD", 60),

    Add("+", 70),
    Subtract("-", 70),

    SubGt("->", 20),
    SubGtGt("->>", 20),
    PoundGt("#>", 20),
    PoundGtGt("#>>", 20),
    QuesQues("??", 20),
    QuesBar("?|", 20),
    QuesQuesBar("??|", 20),
    QuesAmp("?&", 20),

    LeftShift("<<", 80),
    LeftShiftUnsigned("<<<", 80),
    RightShift(">>", 80),
    RightShiftUnsigned(">>>", 80),

    BitwiseAnd("&", 90),
    BitwiseOr("|", 100),

    GreaterThan(">", 110),
    GreaterThanOrEqual(">=", 110),
    Is("IS", 110),
    LessThan("<", 110),
    LessThanOrEqual("<=", 110),
    LessThanOrEqualOrGreaterThan("<=>", 110),
    LessThanOrGreater("<>", 110),

    IsDistinctFrom("IS DISTINCT FROM", 110),
    IsNotDistinctFrom("IS NOT DISTINCT FROM", 110),

    Like("LIKE", 110),
    SoudsLike("SOUNDS LIKE", 110),
    NotLike("NOT LIKE", 110),

    ILike("ILIKE", 110),
    NotILike("NOT ILIKE", 110),
    AT_AT("@@", 110), // postgresql textsearch
    SIMILAR_TO("SIMILAR TO", 110),
    POSIX_Regular_Match("~", 110),
    POSIX_Regular_Match_Insensitive("~*", 110),
    POSIX_Regular_Not_Match("!~", 110),
    POSIX_Regular_Not_Match_POSIX_Regular_Match_Insensitive("!~*", 110),
    Array_Contains("@>", 110),
    Array_ContainedBy("<@", 110),
    SAME_AS("~=", 110),
    JSONContains("?", 110),

    RLike("RLIKE", 110),
    NotRLike("NOT RLIKE", 110),

    NotEqual("!=", 110),
    NotLessThan("!<", 110),
    NotGreaterThan("!>", 110),
    IsNot("IS NOT", 110),
    Escape("ESCAPE", 110),
    RegExp("REGEXP", 110),
    NotRegExp("NOT REGEXP", 110),
    Equality("=", 110),

    BitwiseNot("!", 130),
    Concat("||", 140),

    BooleanAnd("AND", 140),
    BooleanXor("XOR", 150),
    BooleanOr("OR", 160),
    Assignment(":=", 169),

    PG_And("&&", 140),
    PG_ST_DISTANCE("<->", 20);

    public static int getPriority(SQLBinaryOperator operator) {
        return 0;
    }

    public final String name;
    public final String nameLCase;
    public final int priority;

    SQLBinaryOperator(String name, int priority) {
        this.name = name;
        this.nameLCase = name.toLowerCase();
        this.priority = priority;
    }

    public String getName() {
        return this.name;
    }

    public int getPriority() {
        return this.priority;
    }

    public boolean isRelational() {
        switch (this) {
            case Equality:
            case Like:
            case SoudsLike:
            case NotEqual:
            case GreaterThan:
            case GreaterThanOrEqual:
            case LessThan:
            case LessThanOrEqual:
            case LessThanOrGreater:
            case NotLike:
            case NotLessThan:
            case NotGreaterThan:
            case RLike:
            case NotRLike:
            case RegExp:
            case NotRegExp:
            case Is:
            case IsNot:
                return true;
            default:
                return false;
        }
    }

    public boolean isLogical() {
        return this == BooleanAnd || this == BooleanOr || this == BooleanXor;
    }

    public boolean isArithmetic() {
        switch (this) {
            case Add:
            case Subtract:
            case Multiply:
            case Divide:
            case DIV:
            case Modulus:
            case Mod:
                return true;
            default:
                return false;
        }
    }

    public static SQLBinaryOperator from(String str) {
        if (str == null) {
            return null;
        }

        for (SQLBinaryOperator value : values()) {
            if (value.name.equals(str)) {
                return value;
            }
        }

        return valueOf(str);
    }
}
