// 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'

    var Pos = CodeMirror.Pos

    function findParagraph(cm, pos, options) {
        var startRE = options.paragraphStart || cm.getHelper(pos, 'paragraphStart')
        for (var start = pos.line, first = cm.firstLine(); start > first; --start) {
            var line = cm.getLine(start)
            if (startRE && startRE.test(line)) break
            if (!/\S/.test(line)) {
                ++start
                break
            }
        }
        var endRE = options.paragraphEnd || cm.getHelper(pos, 'paragraphEnd')
        for (var end = pos.line + 1, last = cm.lastLine(); end <= last; ++end) {
            var line = cm.getLine(end)
            if (endRE && endRE.test(line)) {
                ++end
                break
            }
            if (!/\S/.test(line)) break
        }
        return { from: start, to: end }
    }

    function findBreakPoint(text, column, wrapOn, killTrailingSpace, forceBreak) {
        var at = column
        while (at < text.length && text.charAt(at) == ' ') at++
        for (; at > 0; --at) if (wrapOn.test(text.slice(at - 1, at + 1))) break

        if (!forceBreak && at <= text.match(/^[ \t]*/)[0].length) {
            // didn't find a break point before column, in non-forceBreak mode try to
            // find one after 'column'.
            for (at = column + 1; at < text.length - 1; ++at) {
                if (wrapOn.test(text.slice(at - 1, at + 1))) break
            }
        }

        for (var first = true; ; first = false) {
            var endOfText = at
            if (killTrailingSpace) while (text.charAt(endOfText - 1) == ' ') --endOfText
            if (endOfText == 0 && first) at = column
            else return { from: endOfText, to: at }
        }
    }

    function wrapRange(cm, from, to, options) {
        from = cm.clipPos(from)
        to = cm.clipPos(to)
        var column = options.column || 80
        var wrapOn = options.wrapOn || /\s\S|-[^\.\d]/
        var forceBreak = options.forceBreak !== false
        var killTrailing = options.killTrailingSpace !== false
        var changes = [],
            curLine = '',
            curNo = from.line
        var lines = cm.getRange(from, to, false)
        if (!lines.length) return null
        var leadingSpace = lines[0].match(/^[ \t]*/)[0]
        if (leadingSpace.length >= column) column = leadingSpace.length + 1

        for (var i = 0; i < lines.length; ++i) {
            var text = lines[i],
                oldLen = curLine.length,
                spaceInserted = 0
            if (curLine && text && !wrapOn.test(curLine.charAt(curLine.length - 1) + text.charAt(0))) {
                curLine += ' '
                spaceInserted = 1
            }
            var spaceTrimmed = ''
            if (i) {
                spaceTrimmed = text.match(/^\s*/)[0]
                text = text.slice(spaceTrimmed.length)
            }
            curLine += text
            if (i) {
                var firstBreak = curLine.length > column && leadingSpace == spaceTrimmed && findBreakPoint(curLine, column, wrapOn, killTrailing, forceBreak)
                // If this isn't broken, or is broken at a different point, remove old break
                if (!firstBreak || firstBreak.from != oldLen || firstBreak.to != oldLen + spaceInserted) {
                    changes.push({ text: [spaceInserted ? ' ' : ''], from: Pos(curNo, oldLen), to: Pos(curNo + 1, spaceTrimmed.length) })
                } else {
                    curLine = leadingSpace + text
                    ++curNo
                }
            }
            while (curLine.length > column) {
                var bp = findBreakPoint(curLine, column, wrapOn, killTrailing, forceBreak)
                if (bp.from != bp.to || (forceBreak && leadingSpace !== curLine.slice(0, bp.to))) {
                    changes.push({ text: ['', leadingSpace], from: Pos(curNo, bp.from), to: Pos(curNo, bp.to) })
                    curLine = leadingSpace + curLine.slice(bp.to)
                    ++curNo
                } else {
                    break
                }
            }
        }
        if (changes.length)
            cm.operation(function () {
                for (var i = 0; i < changes.length; ++i) {
                    var change = changes[i]
                    if (change.text || CodeMirror.cmpPos(change.from, change.to)) cm.replaceRange(change.text, change.from, change.to)
                }
            })
        return changes.length ? { from: changes[0].from, to: CodeMirror.changeEnd(changes[changes.length - 1]) } : null
    }

    CodeMirror.defineExtension('wrapParagraph', function (pos, options) {
        options = options || {}
        if (!pos) pos = this.getCursor()
        var para = findParagraph(this, pos, options)
        return wrapRange(this, Pos(para.from, 0), Pos(para.to - 1), options)
    })

    CodeMirror.commands.wrapLines = function (cm) {
        cm.operation(function () {
            var ranges = cm.listSelections(),
                at = cm.lastLine() + 1
            for (var i = ranges.length - 1; i >= 0; i--) {
                var range = ranges[i],
                    span
                if (range.empty()) {
                    var para = findParagraph(cm, range.head, {})
                    span = { from: Pos(para.from, 0), to: Pos(para.to - 1) }
                } else {
                    span = { from: range.from(), to: range.to() }
                }
                if (span.to.line >= at) continue
                at = span.from.line
                wrapRange(cm, span.from, span.to, {})
            }
        })
    }

    CodeMirror.defineExtension('wrapRange', function (from, to, options) {
        return wrapRange(this, from, to, options || {})
    })

    CodeMirror.defineExtension('wrapParagraphsInRange', function (from, to, options) {
        options = options || {}
        var cm = this,
            paras = []
        for (var line = from.line; line <= to.line; ) {
            var para = findParagraph(cm, Pos(line, 0), options)
            paras.push(para)
            line = para.to
        }
        var madeChange = false
        if (paras.length)
            cm.operation(function () {
                for (var i = paras.length - 1; i >= 0; --i) madeChange = madeChange || wrapRange(cm, Pos(paras[i].from, 0), Pos(paras[i].to - 1), options)
            })
        return madeChange
    })
})