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

/**
 * Link to the project's GitHub page:
 * https://github.com/pickhardt/coffeescript-codemirror-mode
 */
;(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('coffeescript', function (conf, parserConf) {
        var ERRORCLASS = 'error'

        function wordRegexp(words) {
            return new RegExp('^((' + words.join(')|(') + '))\\b')
        }

        var operators = /^(?:->|=>|\+[+=]?|-[\-=]?|\*[\*=]?|\/[\/=]?|[=!]=|<[><]?=?|>>?=?|%=?|&=?|\|=?|\^=?|\~|!|\?|(or|and|\|\||&&|\?)=)/
        var delimiters = /^(?:[()\[\]{},:`=;]|\.\.?\.?)/
        var identifiers = /^[_A-Za-z$][_A-Za-z$0-9]*/
        var atProp = /^@[_A-Za-z$][_A-Za-z$0-9]*/

        var wordOperators = wordRegexp(['and', 'or', 'not', 'is', 'isnt', 'in', 'instanceof', 'typeof'])
        var indentKeywords = ['for', 'while', 'loop', 'if', 'unless', 'else', 'switch', 'try', 'catch', 'finally', 'class']
        var commonKeywords = ['break', 'by', 'continue', 'debugger', 'delete', 'do', 'in', 'of', 'new', 'return', 'then', 'this', '@', 'throw', 'when', 'until', 'extends']

        var keywords = wordRegexp(indentKeywords.concat(commonKeywords))

        indentKeywords = wordRegexp(indentKeywords)

        var stringPrefixes = /^('{3}|\"{3}|['\"])/
        var regexPrefixes = /^(\/{3}|\/)/
        var commonConstants = ['Infinity', 'NaN', 'undefined', 'null', 'true', 'false', 'on', 'off', 'yes', 'no']
        var constants = wordRegexp(commonConstants)

        // Tokenizers
        function tokenBase(stream, state) {
            // Handle scope changes
            if (stream.sol()) {
                if (state.scope.align === null) state.scope.align = false
                var scopeOffset = state.scope.offset
                if (stream.eatSpace()) {
                    var lineOffset = stream.indentation()
                    if (lineOffset > scopeOffset && state.scope.type == 'coffee') {
                        return 'indent'
                    } else if (lineOffset < scopeOffset) {
                        return 'dedent'
                    }
                    return null
                } else {
                    if (scopeOffset > 0) {
                        dedent(stream, state)
                    }
                }
            }
            if (stream.eatSpace()) {
                return null
            }

            var ch = stream.peek()

            // Handle docco title comment (single line)
            if (stream.match('####')) {
                stream.skipToEnd()
                return 'comment'
            }

            // Handle multi line comments
            if (stream.match('###')) {
                state.tokenize = longComment
                return state.tokenize(stream, state)
            }

            // Single line comment
            if (ch === '#') {
                stream.skipToEnd()
                return 'comment'
            }

            // Handle number literals
            if (stream.match(/^-?[0-9\.]/, false)) {
                var floatLiteral = false
                // Floats
                if (stream.match(/^-?\d*\.\d+(e[\+\-]?\d+)?/i)) {
                    floatLiteral = true
                }
                if (stream.match(/^-?\d+\.\d*/)) {
                    floatLiteral = true
                }
                if (stream.match(/^-?\.\d+/)) {
                    floatLiteral = true
                }

                if (floatLiteral) {
                    // prevent from getting extra . on 1..
                    if (stream.peek() == '.') {
                        stream.backUp(1)
                    }
                    return 'number'
                }
                // Integers
                var intLiteral = false
                // Hex
                if (stream.match(/^-?0x[0-9a-f]+/i)) {
                    intLiteral = true
                }
                // Decimal
                if (stream.match(/^-?[1-9]\d*(e[\+\-]?\d+)?/)) {
                    intLiteral = true
                }
                // Zero by itself with no other piece of number.
                if (stream.match(/^-?0(?![\dx])/i)) {
                    intLiteral = true
                }
                if (intLiteral) {
                    return 'number'
                }
            }

            // Handle strings
            if (stream.match(stringPrefixes)) {
                state.tokenize = tokenFactory(stream.current(), false, 'string')
                return state.tokenize(stream, state)
            }
            // Handle regex literals
            if (stream.match(regexPrefixes)) {
                if (stream.current() != '/' || stream.match(/^.*\//, false)) {
                    // prevent highlight of division
                    state.tokenize = tokenFactory(stream.current(), true, 'string-2')
                    return state.tokenize(stream, state)
                } else {
                    stream.backUp(1)
                }
            }

            // Handle operators and delimiters
            if (stream.match(operators) || stream.match(wordOperators)) {
                return 'operator'
            }
            if (stream.match(delimiters)) {
                return 'punctuation'
            }

            if (stream.match(constants)) {
                return 'atom'
            }

            if (stream.match(atProp) || (state.prop && stream.match(identifiers))) {
                return 'property'
            }

            if (stream.match(keywords)) {
                return 'keyword'
            }

            if (stream.match(identifiers)) {
                return 'variable'
            }

            // Handle non-detected items
            stream.next()
            return ERRORCLASS
        }

        function tokenFactory(delimiter, singleline, outclass) {
            return function (stream, state) {
                while (!stream.eol()) {
                    stream.eatWhile(/[^'"\/\\]/)
                    if (stream.eat('\\')) {
                        stream.next()
                        if (singleline && stream.eol()) {
                            return outclass
                        }
                    } else if (stream.match(delimiter)) {
                        state.tokenize = tokenBase
                        return outclass
                    } else {
                        stream.eat(/['"\/]/)
                    }
                }
                if (singleline) {
                    if (parserConf.singleLineStringErrors) {
                        outclass = ERRORCLASS
                    } else {
                        state.tokenize = tokenBase
                    }
                }
                return outclass
            }
        }

        function longComment(stream, state) {
            while (!stream.eol()) {
                stream.eatWhile(/[^#]/)
                if (stream.match('###')) {
                    state.tokenize = tokenBase
                    break
                }
                stream.eatWhile('#')
            }
            return 'comment'
        }

        function indent(stream, state, type) {
            type = type || 'coffee'
            var offset = 0,
                align = false,
                alignOffset = null
            for (var scope = state.scope; scope; scope = scope.prev) {
                if (scope.type === 'coffee' || scope.type == '}') {
                    offset = scope.offset + conf.indentUnit
                    break
                }
            }
            if (type !== 'coffee') {
                align = null
                alignOffset = stream.column() + stream.current().length
            } else if (state.scope.align) {
                state.scope.align = false
            }
            state.scope = {
                offset: offset,
                type: type,
                prev: state.scope,
                align: align,
                alignOffset: alignOffset,
            }
        }

        function dedent(stream, state) {
            if (!state.scope.prev) return
            if (state.scope.type === 'coffee') {
                var _indent = stream.indentation()
                var matched = false
                for (var scope = state.scope; scope; scope = scope.prev) {
                    if (_indent === scope.offset) {
                        matched = true
                        break
                    }
                }
                if (!matched) {
                    return true
                }
                while (state.scope.prev && state.scope.offset !== _indent) {
                    state.scope = state.scope.prev
                }
                return false
            } else {
                state.scope = state.scope.prev
                return false
            }
        }

        function tokenLexer(stream, state) {
            var style = state.tokenize(stream, state)
            var current = stream.current()

            // Handle scope changes.
            if (current === 'return') {
                state.dedent = true
            }
            if (((current === '->' || current === '=>') && stream.eol()) || style === 'indent') {
                indent(stream, state)
            }
            var delimiter_index = '[({'.indexOf(current)
            if (delimiter_index !== -1) {
                indent(stream, state, '])}'.slice(delimiter_index, delimiter_index + 1))
            }
            if (indentKeywords.exec(current)) {
                indent(stream, state)
            }
            if (current == 'then') {
                dedent(stream, state)
            }

            if (style === 'dedent') {
                if (dedent(stream, state)) {
                    return ERRORCLASS
                }
            }
            delimiter_index = '])}'.indexOf(current)
            if (delimiter_index !== -1) {
                while (state.scope.type == 'coffee' && state.scope.prev) state.scope = state.scope.prev
                if (state.scope.type == current) state.scope = state.scope.prev
            }
            if (state.dedent && stream.eol()) {
                if (state.scope.type == 'coffee' && state.scope.prev) state.scope = state.scope.prev
                state.dedent = false
            }

            return style
        }

        var external = {
            startState: function (basecolumn) {
                return {
                    tokenize: tokenBase,
                    scope: { offset: basecolumn || 0, type: 'coffee', prev: null, align: false },
                    prop: false,
                    dedent: 0,
                }
            },

            token: function (stream, state) {
                var fillAlign = state.scope.align === null && state.scope
                if (fillAlign && stream.sol()) fillAlign.align = false

                var style = tokenLexer(stream, state)
                if (style && style != 'comment') {
                    if (fillAlign) fillAlign.align = true
                    state.prop = style == 'punctuation' && stream.current() == '.'
                }

                return style
            },

            indent: function (state, text) {
                if (state.tokenize != tokenBase) return 0
                var scope = state.scope
                var closer = text && '])}'.indexOf(text.charAt(0)) > -1
                if (closer) while (scope.type == 'coffee' && scope.prev) scope = scope.prev
                var closes = closer && scope.type === text.charAt(0)
                if (scope.align) return scope.alignOffset - (closes ? 1 : 0)
                else return (closes ? scope.prev : scope).offset
            },

            lineComment: '#',
            fold: 'indent',
        }
        return external
    })

    // IANA registered media type
    // https://www.iana.org/assignments/media-types/
    CodeMirror.defineMIME('application/vnd.coffeescript', 'coffeescript')

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