/**
 * Copyright (C) 2018 Glayzzle (BSD3 License)
 * @authors https://github.com/glayzzle/php-parser/graphs/contributors
 * @url http://glayzzle.com
 */
"use strict";

module.exports = {
  T_STRING: function () {
    const token = this.yytext.toLowerCase();
    let id = this.keywords[token];
    if (typeof id !== "number") {
      if (token === "yield") {
        if (this.version >= 700 && this.tryMatch(" from")) {
          this.consume(5);
          id = this.tok.T_YIELD_FROM;
        } else {
          id = this.tok.T_YIELD;
        }
      } else {
        id = this.tok.T_STRING;
        if (token === "b" || token === "B") {
          const ch = this.input();
          if (ch === '"') {
            return this.ST_DOUBLE_QUOTES();
          } else if (ch === "'") {
            return this.T_CONSTANT_ENCAPSED_STRING();
          } else if (ch) {
            this.unput(1);
          }
        }
      }
    }

    // https://github.com/php/php-src/blob/master/Zend/zend_language_scanner.l#L1546
    if (id === this.tok.T_ENUM) {
      if (this.version < 801) {
        return this.tok.T_STRING;
      }
      const initial = this.offset;
      let ch = this.input();
      while (ch == " ") {
        ch = this.input();
      }
      let isEnum = false;
      if (this.is_LABEL_START()) {
        while (this.is_LABEL()) {
          ch += this.input();
        }
        const label = ch.slice(0, -1).toLowerCase();
        isEnum = label !== "extends" && label !== "implements";
      }

      this.unput(this.offset - initial);
      return isEnum ? this.tok.T_ENUM : this.tok.T_STRING;
    }

    if (this.offset < this.size && id !== this.tok.T_YIELD_FROM) {
      // If immediately followed by a backslash, this is a T_NAME_RELATIVE or T_NAME_QUALIFIED.
      let ch = this.input();
      if (ch === "\\") {
        id =
          token === "namespace"
            ? this.tok.T_NAME_RELATIVE
            : this.tok.T_NAME_QUALIFIED;
        do {
          if (this._input[this.offset] === "{") {
            // e.g. when using group use statements, the last '\\' is followed by a '{'
            this.input();
            break;
          }

          this.consume_LABEL();
          ch = this.input();
        } while (ch === "\\");
      }

      if (ch) {
        this.unput(1);
      }
    }

    return id;
  },
  // reads a custom token
  consume_TOKEN: function () {
    const ch = this._input[this.offset - 1];
    const fn = this.tokenTerminals[ch];
    if (fn) {
      return fn.apply(this, []);
    } else {
      return this.yytext;
    }
  },
  // list of special char tokens
  tokenTerminals: {
    $: function () {
      this.offset++;
      if (this.is_LABEL_START()) {
        this.offset--;
        this.consume_LABEL();
        return this.tok.T_VARIABLE;
      } else {
        this.offset--;
        return "$";
      }
    },
    "-": function () {
      const nchar = this._input[this.offset];
      if (nchar === ">") {
        this.begin("ST_LOOKING_FOR_PROPERTY").input();
        return this.tok.T_OBJECT_OPERATOR;
      } else if (nchar === "-") {
        this.input();
        return this.tok.T_DEC;
      } else if (nchar === "=") {
        this.input();
        return this.tok.T_MINUS_EQUAL;
      }
      return "-";
    },
    "\\": function () {
      if (this.offset < this.size) {
        this.input();
        if (this.is_LABEL_START()) {
          let ch;
          do {
            if (this._input[this.offset] === "{") {
              // e.g. when using group use statements, the last '\\' is followed by a '{'
              this.input();
              break;
            }

            this.consume_LABEL();
            ch = this.input();
          } while (ch === "\\");

          this.unput(1);

          return this.tok.T_NAME_FULLY_QUALIFIED;
        } else {
          this.unput(1);
        }
      }
      return this.tok.T_NS_SEPARATOR;
    },
    "/": function () {
      if (this._input[this.offset] === "=") {
        this.input();
        return this.tok.T_DIV_EQUAL;
      }
      return "/";
    },
    ":": function () {
      if (this._input[this.offset] === ":") {
        this.input();
        return this.tok.T_DOUBLE_COLON;
      } else {
        return ":";
      }
    },
    "(": function () {
      const initial = this.offset;
      this.input();
      if (this.is_TABSPACE()) {
        this.consume_TABSPACE().input();
      }
      if (this.is_LABEL_START()) {
        const yylen = this.yytext.length;
        this.consume_LABEL();
        const castToken = this.yytext.substring(yylen - 1).toLowerCase();
        const castId = this.castKeywords[castToken];
        if (typeof castId === "number") {
          this.input();
          if (this.is_TABSPACE()) {
            this.consume_TABSPACE().input();
          }
          if (this._input[this.offset - 1] === ")") {
            return castId;
          }
        }
      }
      // revert the check
      this.unput(this.offset - initial);
      return "(";
    },
    "=": function () {
      const nchar = this._input[this.offset];
      if (nchar === ">") {
        this.input();
        return this.tok.T_DOUBLE_ARROW;
      } else if (nchar === "=") {
        if (this._input[this.offset + 1] === "=") {
          this.consume(2);
          return this.tok.T_IS_IDENTICAL;
        } else {
          this.input();
          return this.tok.T_IS_EQUAL;
        }
      }
      return "=";
    },
    "+": function () {
      const nchar = this._input[this.offset];
      if (nchar === "+") {
        this.input();
        return this.tok.T_INC;
      } else if (nchar === "=") {
        this.input();
        return this.tok.T_PLUS_EQUAL;
      }
      return "+";
    },
    "!": function () {
      if (this._input[this.offset] === "=") {
        if (this._input[this.offset + 1] === "=") {
          this.consume(2);
          return this.tok.T_IS_NOT_IDENTICAL;
        } else {
          this.input();
          return this.tok.T_IS_NOT_EQUAL;
        }
      }
      return "!";
    },
    "?": function () {
      if (this.version >= 700 && this._input[this.offset] === "?") {
        if (this.version >= 704 && this._input[this.offset + 1] === "=") {
          this.consume(2);
          return this.tok.T_COALESCE_EQUAL;
        } else {
          this.input();
          return this.tok.T_COALESCE;
        }
      }
      if (
        this.version >= 800 &&
        this._input[this.offset] === "-" &&
        this._input[this.offset + 1] === ">"
      ) {
        this.consume(2);
        return this.tok.T_NULLSAFE_OBJECT_OPERATOR;
      }
      return "?";
    },
    "<": function () {
      let nchar = this._input[this.offset];
      if (nchar === "<") {
        nchar = this._input[this.offset + 1];
        if (nchar === "=") {
          this.consume(2);
          return this.tok.T_SL_EQUAL;
        } else if (nchar === "<") {
          if (this.is_HEREDOC()) {
            return this.tok.T_START_HEREDOC;
          }
        }
        this.input();
        return this.tok.T_SL;
      } else if (nchar === "=") {
        this.input();
        if (this.version >= 700 && this._input[this.offset] === ">") {
          this.input();
          return this.tok.T_SPACESHIP;
        } else {
          return this.tok.T_IS_SMALLER_OR_EQUAL;
        }
      } else if (nchar === ">") {
        this.input();
        return this.tok.T_IS_NOT_EQUAL;
      }
      return "<";
    },
    ">": function () {
      let nchar = this._input[this.offset];
      if (nchar === "=") {
        this.input();
        return this.tok.T_IS_GREATER_OR_EQUAL;
      } else if (nchar === ">") {
        nchar = this._input[this.offset + 1];
        if (nchar === "=") {
          this.consume(2);
          return this.tok.T_SR_EQUAL;
        } else {
          this.input();
          return this.tok.T_SR;
        }
      }
      return ">";
    },
    "*": function () {
      const nchar = this._input[this.offset];
      if (nchar === "=") {
        this.input();
        return this.tok.T_MUL_EQUAL;
      } else if (nchar === "*") {
        this.input();
        if (this._input[this.offset] === "=") {
          this.input();
          return this.tok.T_POW_EQUAL;
        } else {
          return this.tok.T_POW;
        }
      }
      return "*";
    },
    ".": function () {
      const nchar = this._input[this.offset];
      if (nchar === "=") {
        this.input();
        return this.tok.T_CONCAT_EQUAL;
      } else if (nchar === "." && this._input[this.offset + 1] === ".") {
        this.consume(2);
        return this.tok.T_ELLIPSIS;
      }
      return ".";
    },
    "%": function () {
      if (this._input[this.offset] === "=") {
        this.input();
        return this.tok.T_MOD_EQUAL;
      }
      return "%";
    },
    "&": function () {
      const nchar = this._input[this.offset];
      if (nchar === "=") {
        this.input();
        return this.tok.T_AND_EQUAL;
      } else if (nchar === "&") {
        this.input();
        return this.tok.T_BOOLEAN_AND;
      }
      return "&";
    },
    "|": function () {
      const nchar = this._input[this.offset];
      if (nchar === "=") {
        this.input();
        return this.tok.T_OR_EQUAL;
      } else if (nchar === "|") {
        this.input();
        return this.tok.T_BOOLEAN_OR;
      }
      return "|";
    },
    "^": function () {
      if (this._input[this.offset] === "=") {
        this.input();
        return this.tok.T_XOR_EQUAL;
      }
      return "^";
    },
  },
};