// 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('smalltalk', function (config) {
        var specialChars = /[+\-\/\\*~<>=@%|&?!.,:;^]/
        var keywords = /true|false|nil|self|super|thisContext/

        var Context = function (tokenizer, parent) {
            this.next = tokenizer
            this.parent = parent
        }

        var Token = function (name, context, eos) {
            this.name = name
            this.context = context
            this.eos = eos
        }

        var State = function () {
            this.context = new Context(next, null)
            this.expectVariable = true
            this.indentation = 0
            this.userIndentationDelta = 0
        }

        State.prototype.userIndent = function (indentation) {
            this.userIndentationDelta = indentation > 0 ? indentation / config.indentUnit - this.indentation : 0
        }

        var next = function (stream, context, state) {
            var token = new Token(null, context, false)
            var aChar = stream.next()

            if (aChar === '"') {
                token = nextComment(stream, new Context(nextComment, context))
            } else if (aChar === "'") {
                token = nextString(stream, new Context(nextString, context))
            } else if (aChar === '#') {
                if (stream.peek() === "'") {
                    stream.next()
                    token = nextSymbol(stream, new Context(nextSymbol, context))
                } else {
                    if (stream.eatWhile(/[^\s.{}\[\]()]/)) token.name = 'string-2'
                    else token.name = 'meta'
                }
            } else if (aChar === '$') {
                if (stream.next() === '<') {
                    stream.eatWhile(/[^\s>]/)
                    stream.next()
                }
                token.name = 'string-2'
            } else if (aChar === '|' && state.expectVariable) {
                token.context = new Context(nextTemporaries, context)
            } else if (/[\[\]{}()]/.test(aChar)) {
                token.name = 'bracket'
                token.eos = /[\[{(]/.test(aChar)

                if (aChar === '[') {
                    state.indentation++
                } else if (aChar === ']') {
                    state.indentation = Math.max(0, state.indentation - 1)
                }
            } else if (specialChars.test(aChar)) {
                stream.eatWhile(specialChars)
                token.name = 'operator'
                token.eos = aChar !== ';' // ; cascaded message expression
            } else if (/\d/.test(aChar)) {
                stream.eatWhile(/[\w\d]/)
                token.name = 'number'
            } else if (/[\w_]/.test(aChar)) {
                stream.eatWhile(/[\w\d_]/)
                token.name = state.expectVariable ? (keywords.test(stream.current()) ? 'keyword' : 'variable') : null
            } else {
                token.eos = state.expectVariable
            }

            return token
        }

        var nextComment = function (stream, context) {
            stream.eatWhile(/[^"]/)
            return new Token('comment', stream.eat('"') ? context.parent : context, true)
        }

        var nextString = function (stream, context) {
            stream.eatWhile(/[^']/)
            return new Token('string', stream.eat("'") ? context.parent : context, false)
        }

        var nextSymbol = function (stream, context) {
            stream.eatWhile(/[^']/)
            return new Token('string-2', stream.eat("'") ? context.parent : context, false)
        }

        var nextTemporaries = function (stream, context) {
            var token = new Token(null, context, false)
            var aChar = stream.next()

            if (aChar === '|') {
                token.context = context.parent
                token.eos = true
            } else {
                stream.eatWhile(/[^|]/)
                token.name = 'variable'
            }

            return token
        }

        return {
            startState: function () {
                return new State()
            },

            token: function (stream, state) {
                state.userIndent(stream.indentation())

                if (stream.eatSpace()) {
                    return null
                }

                var token = state.context.next(stream, state.context, state)
                state.context = token.context
                state.expectVariable = token.eos

                return token.name
            },

            blankLine: function (state) {
                state.userIndent(0)
            },

            indent: function (state, textAfter) {
                var i = state.context.next === next && textAfter && textAfter.charAt(0) === ']' ? -1 : state.userIndentationDelta
                return (state.indentation + i) * config.indentUnit
            },

            electricChars: ']',
        }
    })

    CodeMirror.defineMIME('text/x-stsrc', { name: 'smalltalk' })
})