// 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('fcl', function (config) {
        var indentUnit = config.indentUnit

        var keywords = {
            term: true,
            method: true,
            accu: true,
            rule: true,
            then: true,
            is: true,
            and: true,
            or: true,
            if: true,
            default: true,
        }

        var start_blocks = {
            var_input: true,
            var_output: true,
            fuzzify: true,
            defuzzify: true,
            function_block: true,
            ruleblock: true,
        }

        var end_blocks = {
            end_ruleblock: true,
            end_defuzzify: true,
            end_function_block: true,
            end_fuzzify: true,
            end_var: true,
        }

        var atoms = {
            true: true,
            false: true,
            nan: true,
            real: true,
            min: true,
            max: true,
            cog: true,
            cogs: true,
        }

        var isOperatorChar = /[+\-*&^%:=<>!|\/]/

        function tokenBase(stream, state) {
            var ch = stream.next()

            if (/[\d\.]/.test(ch)) {
                if (ch == '.') {
                    stream.match(/^[0-9]+([eE][\-+]?[0-9]+)?/)
                } else if (ch == '0') {
                    stream.match(/^[xX][0-9a-fA-F]+/) || stream.match(/^0[0-7]+/)
                } else {
                    stream.match(/^[0-9]*\.?[0-9]*([eE][\-+]?[0-9]+)?/)
                }
                return 'number'
            }

            if (ch == '/' || ch == '(') {
                if (stream.eat('*')) {
                    state.tokenize = tokenComment
                    return tokenComment(stream, state)
                }
                if (stream.eat('/')) {
                    stream.skipToEnd()
                    return 'comment'
                }
            }
            if (isOperatorChar.test(ch)) {
                stream.eatWhile(isOperatorChar)
                return 'operator'
            }
            stream.eatWhile(/[\w\$_\xa1-\uffff]/)

            var cur = stream.current().toLowerCase()
            if (keywords.propertyIsEnumerable(cur) || start_blocks.propertyIsEnumerable(cur) || end_blocks.propertyIsEnumerable(cur)) {
                return 'keyword'
            }
            if (atoms.propertyIsEnumerable(cur)) return 'atom'
            return 'variable'
        }

        function tokenComment(stream, state) {
            var maybeEnd = false,
                ch
            while ((ch = stream.next())) {
                if ((ch == '/' || ch == ')') && maybeEnd) {
                    state.tokenize = tokenBase
                    break
                }
                maybeEnd = ch == '*'
            }
            return 'comment'
        }

        function Context(indented, column, type, align, prev) {
            this.indented = indented
            this.column = column
            this.type = type
            this.align = align
            this.prev = prev
        }

        function pushContext(state, col, type) {
            return (state.context = new Context(state.indented, col, type, null, state.context))
        }

        function popContext(state) {
            if (!state.context.prev) return
            var t = state.context.type
            if (t == 'end_block') state.indented = state.context.indented
            return (state.context = state.context.prev)
        }

        // Interface

        return {
            startState: function (basecolumn) {
                return {
                    tokenize: null,
                    context: new Context((basecolumn || 0) - indentUnit, 0, 'top', false),
                    indented: 0,
                    startOfLine: true,
                }
            },

            token: function (stream, state) {
                var ctx = state.context
                if (stream.sol()) {
                    if (ctx.align == null) ctx.align = false
                    state.indented = stream.indentation()
                    state.startOfLine = true
                }
                if (stream.eatSpace()) return null

                var style = (state.tokenize || tokenBase)(stream, state)
                if (style == 'comment') return style
                if (ctx.align == null) ctx.align = true

                var cur = stream.current().toLowerCase()

                if (start_blocks.propertyIsEnumerable(cur)) pushContext(state, stream.column(), 'end_block')
                else if (end_blocks.propertyIsEnumerable(cur)) popContext(state)

                state.startOfLine = false
                return style
            },

            indent: function (state, textAfter) {
                if (state.tokenize != tokenBase && state.tokenize != null) return 0
                var ctx = state.context

                var closing = end_blocks.propertyIsEnumerable(textAfter)
                if (ctx.align) return ctx.column + (closing ? 0 : 1)
                else return ctx.indented + (closing ? 0 : indentUnit)
            },

            electricChars: 'ryk',
            fold: 'brace',
            blockCommentStart: '(*',
            blockCommentEnd: '*)',
            lineComment: '//',
        }
    })

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