// 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('crystal', function (config) {
        function wordRegExp(words, end) {
            return new RegExp((end ? '' : '^') + '(?:' + words.join('|') + ')' + (end ? '$' : '\\b'))
        }

        function chain(tokenize, stream, state) {
            state.tokenize.push(tokenize)
            return tokenize(stream, state)
        }

        var operators = /^(?:[-+/%|&^]|\*\*?|[<>]{2})/
        var conditionalOperators = /^(?:[=!]~|===|<=>|[<>=!]=?|[|&]{2}|~)/
        var indexingOperators = /^(?:\[\][?=]?)/
        var anotherOperators = /^(?:\.(?:\.{2})?|->|[?:])/
        var idents = /^[a-z_\u009F-\uFFFF][a-zA-Z0-9_\u009F-\uFFFF]*/
        var types = /^[A-Z_\u009F-\uFFFF][a-zA-Z0-9_\u009F-\uFFFF]*/
        var keywords = wordRegExp([
            'abstract',
            'alias',
            'as',
            'asm',
            'begin',
            'break',
            'case',
            'class',
            'def',
            'do',
            'else',
            'elsif',
            'end',
            'ensure',
            'enum',
            'extend',
            'for',
            'fun',
            'if',
            'include',
            'instance_sizeof',
            'lib',
            'macro',
            'module',
            'next',
            'of',
            'out',
            'pointerof',
            'private',
            'protected',
            'rescue',
            'return',
            'require',
            'select',
            'sizeof',
            'struct',
            'super',
            'then',
            'type',
            'typeof',
            'uninitialized',
            'union',
            'unless',
            'until',
            'when',
            'while',
            'with',
            'yield',
            '__DIR__',
            '__END_LINE__',
            '__FILE__',
            '__LINE__',
        ])
        var atomWords = wordRegExp(['true', 'false', 'nil', 'self'])
        var indentKeywordsArray = ['def', 'fun', 'macro', 'class', 'module', 'struct', 'lib', 'enum', 'union', 'do', 'for']
        var indentKeywords = wordRegExp(indentKeywordsArray)
        var indentExpressionKeywordsArray = ['if', 'unless', 'case', 'while', 'until', 'begin', 'then']
        var indentExpressionKeywords = wordRegExp(indentExpressionKeywordsArray)
        var dedentKeywordsArray = ['end', 'else', 'elsif', 'rescue', 'ensure']
        var dedentKeywords = wordRegExp(dedentKeywordsArray)
        var dedentPunctualsArray = ['\\)', '\\}', '\\]']
        var dedentPunctuals = new RegExp('^(?:' + dedentPunctualsArray.join('|') + ')$')
        var nextTokenizer = {
            def: tokenFollowIdent,
            fun: tokenFollowIdent,
            macro: tokenMacroDef,
            class: tokenFollowType,
            module: tokenFollowType,
            struct: tokenFollowType,
            lib: tokenFollowType,
            enum: tokenFollowType,
            union: tokenFollowType,
        }
        var matching = { '[': ']', '{': '}', '(': ')', '<': '>' }

        function tokenBase(stream, state) {
            if (stream.eatSpace()) {
                return null
            }

            // Macros
            if (state.lastToken != '\\' && stream.match('{%', false)) {
                return chain(tokenMacro('%', '%'), stream, state)
            }

            if (state.lastToken != '\\' && stream.match('{{', false)) {
                return chain(tokenMacro('{', '}'), stream, state)
            }

            // Comments
            if (stream.peek() == '#') {
                stream.skipToEnd()
                return 'comment'
            }

            // Variables and keywords
            var matched
            if (stream.match(idents)) {
                stream.eat(/[?!]/)

                matched = stream.current()
                if (stream.eat(':')) {
                    return 'atom'
                } else if (state.lastToken == '.') {
                    return 'property'
                } else if (keywords.test(matched)) {
                    if (indentKeywords.test(matched)) {
                        if (!(matched == 'fun' && state.blocks.indexOf('lib') >= 0) && !(matched == 'def' && state.lastToken == 'abstract')) {
                            state.blocks.push(matched)
                            state.currentIndent += 1
                        }
                    } else if ((state.lastStyle == 'operator' || !state.lastStyle) && indentExpressionKeywords.test(matched)) {
                        state.blocks.push(matched)
                        state.currentIndent += 1
                    } else if (matched == 'end') {
                        state.blocks.pop()
                        state.currentIndent -= 1
                    }

                    if (nextTokenizer.hasOwnProperty(matched)) {
                        state.tokenize.push(nextTokenizer[matched])
                    }

                    return 'keyword'
                } else if (atomWords.test(matched)) {
                    return 'atom'
                }

                return 'variable'
            }

            // Class variables and instance variables
            // or attributes
            if (stream.eat('@')) {
                if (stream.peek() == '[') {
                    return chain(tokenNest('[', ']', 'meta'), stream, state)
                }

                stream.eat('@')
                stream.match(idents) || stream.match(types)
                return 'variable-2'
            }

            // Constants and types
            if (stream.match(types)) {
                return 'tag'
            }

            // Symbols or ':' operator
            if (stream.eat(':')) {
                if (stream.eat('"')) {
                    return chain(tokenQuote('"', 'atom', false), stream, state)
                } else if (stream.match(idents) || stream.match(types) || stream.match(operators) || stream.match(conditionalOperators) || stream.match(indexingOperators)) {
                    return 'atom'
                }
                stream.eat(':')
                return 'operator'
            }

            // Strings
            if (stream.eat('"')) {
                return chain(tokenQuote('"', 'string', true), stream, state)
            }

            // Strings or regexps or macro variables or '%' operator
            if (stream.peek() == '%') {
                var style = 'string'
                var embed = true
                var delim

                if (stream.match('%r')) {
                    // Regexps
                    style = 'string-2'
                    delim = stream.next()
                } else if (stream.match('%w')) {
                    embed = false
                    delim = stream.next()
                } else if (stream.match('%q')) {
                    embed = false
                    delim = stream.next()
                } else {
                    if ((delim = stream.match(/^%([^\w\s=])/))) {
                        delim = delim[1]
                    } else if (stream.match(/^%[a-zA-Z_\u009F-\uFFFF][\w\u009F-\uFFFF]*/)) {
                        // Macro variables
                        return 'meta'
                    } else if (stream.eat('%')) {
                        // '%' operator
                        return 'operator'
                    }
                }

                if (matching.hasOwnProperty(delim)) {
                    delim = matching[delim]
                }
                return chain(tokenQuote(delim, style, embed), stream, state)
            }

            // Here Docs
            if ((matched = stream.match(/^<<-('?)([A-Z]\w*)\1/))) {
                return chain(tokenHereDoc(matched[2], !matched[1]), stream, state)
            }

            // Characters
            if (stream.eat("'")) {
                stream.match(/^(?:[^']|\\(?:[befnrtv0'"]|[0-7]{3}|u(?:[0-9a-fA-F]{4}|\{[0-9a-fA-F]{1,6}\})))/)
                stream.eat("'")
                return 'atom'
            }

            // Numbers
            if (stream.eat('0')) {
                if (stream.eat('x')) {
                    stream.match(/^[0-9a-fA-F_]+/)
                } else if (stream.eat('o')) {
                    stream.match(/^[0-7_]+/)
                } else if (stream.eat('b')) {
                    stream.match(/^[01_]+/)
                }
                return 'number'
            }

            if (stream.eat(/^\d/)) {
                stream.match(/^[\d_]*(?:\.[\d_]+)?(?:[eE][+-]?\d+)?/)
                return 'number'
            }

            // Operators
            if (stream.match(operators)) {
                stream.eat('=') // Operators can follow assign symbol.
                return 'operator'
            }

            if (stream.match(conditionalOperators) || stream.match(anotherOperators)) {
                return 'operator'
            }

            // Parens and braces
            if ((matched = stream.match(/[({[]/, false))) {
                matched = matched[0]
                return chain(tokenNest(matched, matching[matched], null), stream, state)
            }

            // Escapes
            if (stream.eat('\\')) {
                stream.next()
                return 'meta'
            }

            stream.next()
            return null
        }

        function tokenNest(begin, end, style, started) {
            return function (stream, state) {
                if (!started && stream.match(begin)) {
                    state.tokenize[state.tokenize.length - 1] = tokenNest(begin, end, style, true)
                    state.currentIndent += 1
                    return style
                }

                var nextStyle = tokenBase(stream, state)
                if (stream.current() === end) {
                    state.tokenize.pop()
                    state.currentIndent -= 1
                    nextStyle = style
                }

                return nextStyle
            }
        }

        function tokenMacro(begin, end, started) {
            return function (stream, state) {
                if (!started && stream.match('{' + begin)) {
                    state.currentIndent += 1
                    state.tokenize[state.tokenize.length - 1] = tokenMacro(begin, end, true)
                    return 'meta'
                }

                if (stream.match(end + '}')) {
                    state.currentIndent -= 1
                    state.tokenize.pop()
                    return 'meta'
                }

                return tokenBase(stream, state)
            }
        }

        function tokenMacroDef(stream, state) {
            if (stream.eatSpace()) {
                return null
            }

            var matched
            if ((matched = stream.match(idents))) {
                if (matched == 'def') {
                    return 'keyword'
                }
                stream.eat(/[?!]/)
            }

            state.tokenize.pop()
            return 'def'
        }

        function tokenFollowIdent(stream, state) {
            if (stream.eatSpace()) {
                return null
            }

            if (stream.match(idents)) {
                stream.eat(/[!?]/)
            } else {
                stream.match(operators) || stream.match(conditionalOperators) || stream.match(indexingOperators)
            }
            state.tokenize.pop()
            return 'def'
        }

        function tokenFollowType(stream, state) {
            if (stream.eatSpace()) {
                return null
            }

            stream.match(types)
            state.tokenize.pop()
            return 'def'
        }

        function tokenQuote(end, style, embed) {
            return function (stream, state) {
                var escaped = false

                while (stream.peek()) {
                    if (!escaped) {
                        if (stream.match('{%', false)) {
                            state.tokenize.push(tokenMacro('%', '%'))
                            return style
                        }

                        if (stream.match('{{', false)) {
                            state.tokenize.push(tokenMacro('{', '}'))
                            return style
                        }

                        if (embed && stream.match('#{', false)) {
                            state.tokenize.push(tokenNest('#{', '}', 'meta'))
                            return style
                        }

                        var ch = stream.next()

                        if (ch == end) {
                            state.tokenize.pop()
                            return style
                        }

                        escaped = embed && ch == '\\'
                    } else {
                        stream.next()
                        escaped = false
                    }
                }

                return style
            }
        }

        function tokenHereDoc(phrase, embed) {
            return function (stream, state) {
                if (stream.sol()) {
                    stream.eatSpace()
                    if (stream.match(phrase)) {
                        state.tokenize.pop()
                        return 'string'
                    }
                }

                var escaped = false
                while (stream.peek()) {
                    if (!escaped) {
                        if (stream.match('{%', false)) {
                            state.tokenize.push(tokenMacro('%', '%'))
                            return 'string'
                        }

                        if (stream.match('{{', false)) {
                            state.tokenize.push(tokenMacro('{', '}'))
                            return 'string'
                        }

                        if (embed && stream.match('#{', false)) {
                            state.tokenize.push(tokenNest('#{', '}', 'meta'))
                            return 'string'
                        }

                        escaped = embed && stream.next() == '\\'
                    } else {
                        stream.next()
                        escaped = false
                    }
                }

                return 'string'
            }
        }

        return {
            startState: function () {
                return {
                    tokenize: [tokenBase],
                    currentIndent: 0,
                    lastToken: null,
                    lastStyle: null,
                    blocks: [],
                }
            },

            token: function (stream, state) {
                var style = state.tokenize[state.tokenize.length - 1](stream, state)
                var token = stream.current()

                if (style && style != 'comment') {
                    state.lastToken = token
                    state.lastStyle = style
                }

                return style
            },

            indent: function (state, textAfter) {
                textAfter = textAfter.replace(/^\s*(?:\{%)?\s*|\s*(?:%\})?\s*$/g, '')

                if (dedentKeywords.test(textAfter) || dedentPunctuals.test(textAfter)) {
                    return config.indentUnit * (state.currentIndent - 1)
                }

                return config.indentUnit * state.currentIndent
            },

            fold: 'indent',
            electricInput: wordRegExp(dedentPunctualsArray.concat(dedentKeywordsArray), true),
            lineComment: '#',
        }
    })

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