// CodeMirror, copyright (c) by Marijn Haverbeke and others
// Distributed under an MIT license: https://codemirror.net/LICENSE

;(function (mod) {
    if (typeof exports == 'object' && typeof module == 'object')
        // CommonJS
        mod(require('../../lib/codemirror'), require('../javascript/javascript'))
    else if (typeof define == 'function' && define.amd)
        // AMD
        define(['../../lib/codemirror', '../javascript/javascript'], mod)
    // Plain browser env
    else mod(CodeMirror)
})(function (CodeMirror) {
    'use strict'

    CodeMirror.defineMode(
        'pegjs',
        function (config) {
            var jsMode = CodeMirror.getMode(config, 'javascript')

            function identifier(stream) {
                return stream.match(/^[a-zA-Z_][a-zA-Z0-9_]*/)
            }

            return {
                startState: function () {
                    return {
                        inString: false,
                        stringType: null,
                        inComment: false,
                        inCharacterClass: false,
                        braced: 0,
                        lhs: true,
                        localState: null,
                    }
                },
                token: function (stream, state) {
                    if (stream)
                        if (!state.inString && !state.inComment && (stream.peek() == '"' || stream.peek() == "'")) {
                            //check for state changes
                            state.stringType = stream.peek()
                            stream.next() // Skip quote
                            state.inString = true // Update state
                        }
                    if (!state.inString && !state.inComment && stream.match('/*')) {
                        state.inComment = true
                    }

                    //return state
                    if (state.inString) {
                        while (state.inString && !stream.eol()) {
                            if (stream.peek() === state.stringType) {
                                stream.next() // Skip quote
                                state.inString = false // Clear flag
                            } else if (stream.peek() === '\\') {
                                stream.next()
                                stream.next()
                            } else {
                                stream.match(/^.[^\\\"\']*/)
                            }
                        }
                        return state.lhs ? 'property string' : 'string' // Token style
                    } else if (state.inComment) {
                        while (state.inComment && !stream.eol()) {
                            if (stream.match('*/')) {
                                state.inComment = false // Clear flag
                            } else {
                                stream.match(/^.[^\*]*/)
                            }
                        }
                        return 'comment'
                    } else if (state.inCharacterClass) {
                        while (state.inCharacterClass && !stream.eol()) {
                            if (!(stream.match(/^[^\]\\]+/) || stream.match(/^\\./))) {
                                state.inCharacterClass = false
                            }
                        }
                    } else if (stream.peek() === '[') {
                        stream.next()
                        state.inCharacterClass = true
                        return 'bracket'
                    } else if (stream.match('//')) {
                        stream.skipToEnd()
                        return 'comment'
                    } else if (state.braced || stream.peek() === '{') {
                        if (state.localState === null) {
                            state.localState = CodeMirror.startState(jsMode)
                        }
                        var token = jsMode.token(stream, state.localState)
                        var text = stream.current()
                        if (!token) {
                            for (var i = 0; i < text.length; i++) {
                                if (text[i] === '{') {
                                    state.braced++
                                } else if (text[i] === '}') {
                                    state.braced--
                                }
                            }
                        }
                        return token
                    } else if (identifier(stream)) {
                        if (stream.peek() === ':') {
                            return 'variable'
                        }
                        return 'variable-2'
                    } else if (['[', ']', '(', ')'].indexOf(stream.peek()) != -1) {
                        stream.next()
                        return 'bracket'
                    } else if (!stream.eatSpace()) {
                        stream.next()
                    }
                    return null
                },
            }
        },
        'javascript'
    )
})