'use strict';

const constants = require('./constants');
const utils = require('./utils');

/**
 * Constants
 */

const {
  MAX_LENGTH,
  POSIX_REGEX_SOURCE,
  REGEX_NON_SPECIAL_CHARS,
  REGEX_SPECIAL_CHARS_BACKREF,
  REPLACEMENTS
} = constants;

/**
 * Helpers
 */

const expandRange = (args, options) => {
  if (typeof options.expandRange === 'function') {
    return options.expandRange(...args, options);
  }

  args.sort();
  const value = `[${args.join('-')}]`;

  try {
    /* eslint-disable-next-line no-new */
    new RegExp(value);
  } catch (ex) {
    return args.map(v => utils.escapeRegex(v)).join('..');
  }

  return value;
};

/**
 * Create the message for a syntax error
 */

const syntaxError = (type, char) => {
  return `Missing ${type}: "${char}" - use "\\\\${char}" to match literal characters`;
};

/**
 * Parse the given input string.
 * @param {String} input
 * @param {Object} options
 * @return {Object}
 */

const parse = (input, options) => {
  if (typeof input !== 'string') {
    throw new TypeError('Expected a string');
  }

  input = REPLACEMENTS[input] || input;

  const opts = { ...options };
  const max = typeof opts.maxLength === 'number' ? Math.min(MAX_LENGTH, opts.maxLength) : MAX_LENGTH;

  let len = input.length;
  if (len > max) {
    throw new SyntaxError(`Input length: ${len}, exceeds maximum allowed length: ${max}`);
  }

  const bos = { type: 'bos', value: '', output: opts.prepend || '' };
  const tokens = [bos];

  const capture = opts.capture ? '' : '?:';
  const win32 = utils.isWindows(options);

  // create constants based on platform, for windows or posix
  const PLATFORM_CHARS = constants.globChars(win32);
  const EXTGLOB_CHARS = constants.extglobChars(PLATFORM_CHARS);

  const {
    DOT_LITERAL,
    PLUS_LITERAL,
    SLASH_LITERAL,
    ONE_CHAR,
    DOTS_SLASH,
    NO_DOT,
    NO_DOT_SLASH,
    NO_DOTS_SLASH,
    QMARK,
    QMARK_NO_DOT,
    STAR,
    START_ANCHOR
  } = PLATFORM_CHARS;

  const globstar = opts => {
    return `(${capture}(?:(?!${START_ANCHOR}${opts.dot ? DOTS_SLASH : DOT_LITERAL}).)*?)`;
  };

  const nodot = opts.dot ? '' : NO_DOT;
  const qmarkNoDot = opts.dot ? QMARK : QMARK_NO_DOT;
  let star = opts.bash === true ? globstar(opts) : STAR;

  if (opts.capture) {
    star = `(${star})`;
  }

  // minimatch options support
  if (typeof opts.noext === 'boolean') {
    opts.noextglob = opts.noext;
  }

  const state = {
    input,
    index: -1,
    start: 0,
    dot: opts.dot === true,
    consumed: '',
    output: '',
    prefix: '',
    backtrack: false,
    negated: false,
    brackets: 0,
    braces: 0,
    parens: 0,
    quotes: 0,
    globstar: false,
    tokens
  };

  input = utils.removePrefix(input, state);
  len = input.length;

  const extglobs = [];
  const braces = [];
  const stack = [];
  let prev = bos;
  let value;

  /**
   * Tokenizing helpers
   */

  const eos = () => state.index === len - 1;
  const peek = state.peek = (n = 1) => input[state.index + n];
  const advance = state.advance = () => input[++state.index] || '';
  const remaining = () => input.slice(state.index + 1);
  const consume = (value = '', num = 0) => {
    state.consumed += value;
    state.index += num;
  };

  const append = token => {
    state.output += token.output != null ? token.output : token.value;
    consume(token.value);
  };

  const negate = () => {
    let count = 1;

    while (peek() === '!' && (peek(2) !== '(' || peek(3) === '?')) {
      advance();
      state.start++;
      count++;
    }

    if (count % 2 === 0) {
      return false;
    }

    state.negated = true;
    state.start++;
    return true;
  };

  const increment = type => {
    state[type]++;
    stack.push(type);
  };

  const decrement = type => {
    state[type]--;
    stack.pop();
  };

  /**
   * Push tokens onto the tokens array. This helper speeds up
   * tokenizing by 1) helping us avoid backtracking as much as possible,
   * and 2) helping us avoid creating extra tokens when consecutive
   * characters are plain text. This improves performance and simplifies
   * lookbehinds.
   */

  const push = tok => {
    if (prev.type === 'globstar') {
      const isBrace = state.braces > 0 && (tok.type === 'comma' || tok.type === 'brace');
      const isExtglob = tok.extglob === true || (extglobs.length && (tok.type === 'pipe' || tok.type === 'paren'));

      if (tok.type !== 'slash' && tok.type !== 'paren' && !isBrace && !isExtglob) {
        state.output = state.output.slice(0, -prev.output.length);
        prev.type = 'star';
        prev.value = '*';
        prev.output = star;
        state.output += prev.output;
      }
    }

    if (extglobs.length && tok.type !== 'paren') {
      extglobs[extglobs.length - 1].inner += tok.value;
    }

    if (tok.value || tok.output) append(tok);
    if (prev && prev.type === 'text' && tok.type === 'text') {
      prev.value += tok.value;
      prev.output = (prev.output || '') + tok.value;
      return;
    }

    tok.prev = prev;
    tokens.push(tok);
    prev = tok;
  };

  const extglobOpen = (type, value) => {
    const token = { ...EXTGLOB_CHARS[value], conditions: 1, inner: '' };

    token.prev = prev;
    token.parens = state.parens;
    token.output = state.output;
    const output = (opts.capture ? '(' : '') + token.open;

    increment('parens');
    push({ type, value, output: state.output ? '' : ONE_CHAR });
    push({ type: 'paren', extglob: true, value: advance(), output });
    extglobs.push(token);
  };

  const extglobClose = token => {
    let output = token.close + (opts.capture ? ')' : '');
    let rest;

    if (token.type === 'negate') {
      let extglobStar = star;

      if (token.inner && token.inner.length > 1 && token.inner.includes('/')) {
        extglobStar = globstar(opts);
      }

      if (extglobStar !== star || eos() || /^\)+$/.test(remaining())) {
        output = token.close = `)$))${extglobStar}`;
      }

      if (token.inner.includes('*') && (rest = remaining()) && /^\.[^\\/.]+$/.test(rest)) {
        // Any non-magical string (`.ts`) or even nested expression (`.{ts,tsx}`) can follow after the closing parenthesis.
        // In this case, we need to parse the string and use it in the output of the original pattern.
        // Suitable patterns: `/!(*.d).ts`, `/!(*.d).{ts,tsx}`, `**/!(*-dbg).@(js)`.
        //
        // Disabling the `fastpaths` option due to a problem with parsing strings as `.ts` in the pattern like `**/!(*.d).ts`.
        const expression = parse(rest, { ...options, fastpaths: false }).output;

        output = token.close = `)${expression})${extglobStar})`;
      }

      if (token.prev.type === 'bos') {
        state.negatedExtglob = true;
      }
    }

    push({ type: 'paren', extglob: true, value, output });
    decrement('parens');
  };

  /**
   * Fast paths
   */

  if (opts.fastpaths !== false && !/(^[*!]|[/()[\]{}"])/.test(input)) {
    let backslashes = false;

    let output = input.replace(REGEX_SPECIAL_CHARS_BACKREF, (m, esc, chars, first, rest, index) => {
      if (first === '\\') {
        backslashes = true;
        return m;
      }

      if (first === '?') {
        if (esc) {
          return esc + first + (rest ? QMARK.repeat(rest.length) : '');
        }
        if (index === 0) {
          return qmarkNoDot + (rest ? QMARK.repeat(rest.length) : '');
        }
        return QMARK.repeat(chars.length);
      }

      if (first === '.') {
        return DOT_LITERAL.repeat(chars.length);
      }

      if (first === '*') {
        if (esc) {
          return esc + first + (rest ? star : '');
        }
        return star;
      }
      return esc ? m : `\\${m}`;
    });

    if