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

    CodeMirror.defineMode('spreadsheet', function () {
        return {
            startState: function () {
                return {
                    stringType: null,
                    stack: [],
                }
            },
            token: function (stream, state) {
                if (!stream) return

                //check for state changes
                if (state.stack.length === 0) {
                    //strings
                    if (stream.peek() == '"' || stream.peek() == "'") {
                        state.stringType = stream.peek()
                        stream.next() // Skip quote
                        state.stack.unshift('string')
                    }
                }

                //return state
                //stack has
                switch (state.stack[0]) {
                    case 'string':
                        while (state.stack[0] === 'string' && !stream.eol()) {
                            if (stream.peek() === state.stringType) {
                                stream.next() // Skip quote
                                state.stack.shift() // Clear flag
                            } else if (stream.peek() === '\\') {
                                stream.next()
                                stream.next()
                            } else {
                                stream.match(/^.[^\\\"\']*/)
                            }
                        }
                        return 'string'

                    case 'characterClass':
                        while (state.stack[0] === 'characterClass' && !stream.eol()) {
                            if (!(stream.match(/^[^\]\\]+/) || stream.match(/^\\./))) state.stack.shift()
                        }
                        return 'operator'
                }

                var peek = stream.peek()

                //no stack
                switch (peek) {
                    case '[':
                        stream.next()
                        state.stack.unshift('characterClass')
                        return 'bracket'
                    case ':':
                        stream.next()
                        return 'operator'
                    case '\\':
                        if (stream.match(/\\[a-z]+/)) return 'string-2'
                        else {
                            stream.next()
                            return 'atom'
                        }
                    case '.':
                    case ',':
                    case ';':
                    case '*':
                    case '-':
                    case '+':
                    case '^':
                    case '<':
                    case '/':
                    case '=':
                        stream.next()
                        return 'atom'
                    case '$':
                        stream.next()
                        return 'builtin'
                }

                if (stream.match(/\d+/)) {
                    if (stream.match(/^\w+/)) return 'error'
                    return 'number'
                } else if (stream.match(/^[a-zA-Z_]\w*/)) {
                    if (stream.match(/(?=[\(.])/, false)) return 'keyword'
                    return 'variable-2'
                } else if (['[', ']', '(', ')', '{', '}'].indexOf(peek) != -1) {
                    stream.next()
                    return 'bracket'
                } else if (!stream.eatSpace()) {
                    stream.next()
                }
                return null
            },
        }
    })

    CodeMirror.defineMIME('text/x-spreadsheet', 'spreadsheet')
})