var Transposer = (function ($) {

    const wrapRegex = /(?:(?:DO|RE|MI|FA|SOL|LA|SI)(?:b|\#)?(?:\d+[\+\-]?)?(?:m?(?:aug|dim|add|b|#)?(?:\d+[\+\-]?)?(?:\/?\d+[\+\-]?)?)(?:\/(?:DO|RE|MI|FA|SOL|LA|SI)(?:b|\#)*)?)/g;
    const lineRegex = /^\s*(?:(?:DO|RE|MI|FA|SOL|LA|SI)(?:b|\#)?(?:\d+[\+\-]?)?(?:m?(?:aug|dim|add|b|#)?(?:\d+[\+\-]?)?(?:\/?\d+[\+\-]?)?)(?:\/(?:DO|RE|MI|FA|SOL|LA|SI)(?:b|\#)*)?\s*)+$/;
    const noteRegex = /\b(?:((?:DO|RE|MI|FA|SOL|LA|SI)(?:b|\#)?)(?=(?:aug|m|dim)?(?:\s|\/))*)/;
    const noteGRe = new RegExp(noteRegex, "g");
    const simpleRegex = /(?:((?:DO|RE|MI|FA|SOL|LA|SI)(?:b|\#)?)((?:\d+[\+\-]?)?(m|aug|dim|add|b|#)?(?:\d+[\+\-]?)?(?:\/?\d+[\+\-]?)?(?:\/((?:DO|RE|MI|FA|SOL|LA|SI)(?:b|\#)*))?))/;

    const legalNotes = ["DO", "REb", "RE", "MIb", "MI", "FA", "FA#", "SOL", "LAb", "LA", "SIb", "SI"];

    const N_KEYS = 12;

    const scales = {
        '#': ['DO', 'DO#', 'RE', 'RE#', 'MI', 'FA', 'FA#', 'SOL', 'SOL#', 'LA', 'LA#', 'SI'],
        'b': ['DO', 'REb', 'RE', 'MIb', 'MI', 'FA', 'SOLb', 'SOL', 'LAb', 'LA', 'SIb', 'SI']
    };

    const Notes = {
        "DO": {
            index: 0,
            type: "N"
        },
        "DO#": {
            index: 1,
            type: "#"
        },
        "REb": {
            index: 1,
            type: "b"
        },
        "RE": {
            index: 2,
            type: "#"
        },
        "RE#": {
            index: 3,
            type: "#"
        },
        "MIb": {
            index: 3,
            type: "b"
        },
        "MI": {
            index: 4,
            type: "#"
        },
        "FA": {
            index: 5,
            type: "b"
        },
        "FA#": {
            index: 6,
            type: "#"
        },
        "SOLb": {
            index: 6,
            type: "b"
        },
        "SOL": {
            index: 7,
            type: "#"
        },
        "SOL#": {
            index: 8,
            type: "#"
        },
        "LAb": {
            index: 8,
            type: "b"
        },
        "LA": {
            index: 9,
            type: "#"
        },
        "LA#": {
            index: 10,
            type: "#"
        },
        "SIb": {
            index: 10,
            type: "b"
        },
        "SI": {
            index: 11,
            type: "#"
        }
    };

    let diffToSimple = {};

    var IS_SIMPLE = 0;


    String.prototype.insertAt = function (pos, str) {
        return [this.slice(0, pos), str, this.slice(pos)].join('');
    };


    function init() {
        var $pre = $('pre');
        var $chiave = $("div.chiave", $pre);
        if ($chiave) {

            var lines = $pre.html().split('\n');
            wrapChords(lines);
            $pre.html(lines.join('\n'));

            /* ---- CONTROLS ---- */
            $('body').on('keydown', function (e) {
                switch (e.which) {
                    case 107: // +
                        pitchUp();
                        break;
                    case 109: // -
                        pitchDown();
                        break;
                    default:
                        break;
                }
            })

                .on('click', '#pitchUp', pitchUp)
                .on('click', '#pitchDown', pitchDown)
                .on('click', '#pitchUpresp', pitchUpresp)
                .on('click', '#pitchDownresp', pitchDownresp)
                .on("click", "#simplify", onSClick)
                .on("click", "#unsimplify", onUSClick);

            $('span.chord').on("mouseover", onChordOver);


            $("#text-magnify, #text-magnify-responsive").click(function () {
                $("#text-reduce, #text-reduce-responsive").removeClass("disabled");
                $('#output-text').html(function (i, val) {
                    if (val < 3) {
                        var prePosition = $('.bottom-ad').offset();
                        var fontSize = parseFloat($('pre').css("font-size"));
                        var fontSize = fontSize + 3 + "px";
                        var lineHeight = parseFloat($('pre').css("line-height"));
                        var lineHeight = lineHeight + 2.8 + "px";
                        $('pre').css({'font-size':fontSize});
                        $('pre').css({'line-height':lineHeight});
                        var ret = val * 1 + 1;
                        return ret > 0 ? "+" + ret : ret;
                    } else {
                        $("#text-magnify, #text-magnify-responsive").addClass("disabled");
                    }
                });
            });

            $("#text-reduce, #text-reduce-responsive").click(function () {
                $("#text-magnify, #text-magnify-responsive").removeClass("disabled");
                $('#output-text').html(function (i, val) {
                    if (val > -1) {
                        var prePosition = $('.bottom-ad').offset();
                        var fontSize = parseFloat($('pre').css("font-size"));
                        var fontSize = fontSize - 3 + "px";
                        var lineHeight = parseFloat($('pre').css("line-height"));
                        var lineHeight = lineHeight - 2.8 + "px";
                        $('pre').css({'font-size':fontSize});
                        $('pre').css({'line-height':lineHeight});
                        var ret = val * 1 - 1;
                        return ret > 0 ? "+" + ret : ret;
                    } else {
                        $("#text-reduce, #text-reduce-responsive").addClass("disabled");
                    }
                });
            });

            restoreFavouriteK($chiave.attr('name'));

        }

    }


    function pitchUp(e) {
        e.preventDefault();
        e.stopPropagation();
        $('#output').html(function (i, val) {
            if (val < 11) {
                transpose(1);
                var ret = val * 1 + 1;
                return ret > 0 ? "+" + ret : ret;
            }
        });
    }

    function pitchUpresp(e) {
        e.preventDefault();
        e.stopPropagation();
        $('#output-responsive').html(function (i, val) {
            if (val < 11) {
                transpose(1);
                var ret = val * 1 + 1;
                return ret > 0 ? "+" + ret : ret;
            }
        });
    }

    function pitchDown(e) {
        e.preventDefault();
        e.stopPropagation();
        $('#output').html(function (i, val) {
            if (val > -11) {
                transpose(-1);
                var ret = val * 1 - 1;
                return ret > 0 ? "+" + ret : ret;
            }
        });
    }

    function pitchDownresp(e) {
        e.preventDefault();
        e.stopPropagation();
        $('#output-responsive').html(function (i, val) {
            if (val > -11) {
                transpose(-1);
                var ret = val * 1 - 1;
                return ret > 0 ? "+" + ret : ret;
            }
        });
    }

    function onSClick(e) {
        e.preventDefault();
        e.stopPropagation();
        if (!IS_SIMPLE) {
            simplify();
            IS_SIMPLE = 1;
            $(this).addClass('checked');
            $(this).attr("id", "unsimplify");
            $('.chord').addClass('simplified');
        }
    }


    function onUSClick(e) {
        e.preventDefault();
        e.stopPropagation();
        if (IS_SIMPLE) {
            unsimplify();
            IS_SIMPLE = 0;
            $(this).removeClass('checked');
            $(this).attr("id", "simplify");
            $('.chord').removeClass('simplified');
        }
    }


    function onChordOver(e) {
        e.preventDefault();
        e.stopPropagation();
        WidgetFactory.newWidget(this);
    }

    function restoreFavouriteK(oldK) {
        var $btn = $('button#asfp-remove-fav-btn');
        if ($btn.length) {
             var newK = $btn.data("key");
             var dlt = delta(Notes[oldK].index, Notes[newK].index);
             for (var i = 1; i < N_KEYS; i++) {
                 var posDlt = delta(Notes[oldK].index, i);
                 var negDlt = delta(Notes[oldK].index, - i);
                 if (newK == shiftKey(oldK, posDlt)) {
                     dlt = posDlt;
                     break;
                 }
                 else if (newK == shiftKey(oldK, negDlt)) {
                     dlt = negDlt;
                     break;
                 }
             }
             transpose(dlt);
            if (dlt == 0 || dlt == 12 || dlt == -12) {
            $('#output').html("0");
             $('#output-responsive').html("0");
            } else if (dlt < -6) {
            var dlt2 = 12 + dlt;
            $('#output').html(dlt2);
             $('#output-responsive').html(dlt2);
            } else if (dlt > 6) {
            var dlt2 = - 12 + dlt;
            $('#output').html(dlt2);
             $('#output-responsive').html(dlt2);
            } else if (dlt > 0) {
            var dlt2 = 12 - dlt;
            $('#output').html("+" + dlt);
             $('#output-responsive').html("+" + dlt);
            } else {
            $('#output').html(dlt);
             $('#output-responsive').html(dlt);
            }
        }
    }


    function transpose(amount) {
        var keys = $('pre > div.chiave');
        keys.each(function () {
            var $key = $(this);
            var oldK = $key.attr("name");

            switch (oldK) {
                case "DO#":
                    oldK = "REb";
                    break;
                case "RE#":
                    oldK = "MIb";
                    break;
                case "SOLb":
                    oldK = "FA#";
                    break;
                case "SOL#":
                    oldK = "LAb";
                    break;
                case "LA#":
                    oldK = "SIb";
                    break;
            }
            var newK = shiftKey(oldK, amount);
            changeNotes(oldK, newK, $key);
            $key.attr("name", newK);
        });
    }


    function changeNotes(oldK, newK, context) {
        $("span.note", context).each(function () {
            var $note = $(this);
            var newNote = changePitch($note.html(), oldK, newK);
            $note.html(newNote);
        });

        $("span.chord[data-old-bass]", context).each(function () {
            var $chord = $(this);
            var $newB = changePitch($chord.attr("data-old-bass"), oldK, newK);
            $chord.attr("data-old-bass", $newB);
        })
    }


    function changePitch(note, oldK, newK) {
        var keyDelta = delta(Notes[oldK].index, Notes[newK].index);
        var newKType = Notes[newK].type;
        var newNoteIndex = circularIndex(Notes[note].index, keyDelta, N_KEYS);
        return (newKType === "N") ? legalNotes[newNoteIndex] : scales[newKType][newNoteIndex];
    }


    function simplify() {
        var chords = $('span.chord');
        chords.each(function () {
            var $chord = $(this);
            var $oldText = $chord.text();
            var matches = simpleRegex.exec($oldText);
            if (matches[2] !== "") {
                $chord.replaceWith(simplifyChord(matches));
            }
        });
    }


    function simplifyChord(matches) {
        var erer = /(\d+[+-]?\d*)/.exec(matches[2]);

        var $rootNote = $("<span/>", {"class": "note"})
            .text(matches[1]);

        var alter = matches[2];

        var $simpleChord = $("<span/>", {"class": "chord"})
            .on("mouseover", onChordOver)
            .append($rootNote);


        var whiteSp = 0;
        var $simpleText = "";

    if (!/dim/.test(alter)) {
        if (/m/.test(alter)) {
            if (!/d/.test(alter)) {
                whiteSp--;
            }
            $simpleText = "m";
            alter = alter.replace(/m/, "");
        }
    }

        whiteSp = whiteSp + alter.length;

        for (var i = 0; i < whiteSp; i++) {
            $simpleText = $simpleText + " ";
        }

        $simpleChord.html($simpleChord.html() + $simpleText);


        if (matches[4]) {
            var alters = alter.split("/");
            if (alters[0]) {
                $simpleChord.attr("data-old", alters[0]);
            }
            $simpleChord.attr("data-old-bass", alters[1]);
        } else {
            $simpleChord.attr("data-old", alter);
        }

        return $simpleChord;
    }


    function unsimplify() {

        $("span.chord[data-old]").each(function () {
            var $chord = $(this);
            var oldAlt = $chord.attr("data-old");

            $chord.html($chord.html().trim());
            $chord.html($chord.html() + oldAlt);
            $chord.removeAttr("data-old");
        });

        $("span.chord[data-old-bass]").each(function () {
            var $chord = $(this);
            var oldB = $chord.attr("data-old-bass");

            $chord.html($chord.html().trim());
            $chord.html($chord.html() + "/")
                .append(
                    $("<span/>", {
                        "class": "note"
                    })
                        .text(oldB)
                );
            $chord.removeAttr("data-old-bass");
        });

    }


    function wrapChords(lines) {
        lines.forEach(function (line, i) {
            if (lineRegex.test(line)) {
                line = insertChordTag(line);
                line = insertNoteTag(line);
                lines[i] = line;
            }
        });
    }


    function insertChordTag(line) {
        var chord;
        var chords = [];
        while ((chord = wrapRegex.exec(line)) !== null) {
            chords.push(chord);
        }
        chords.reverse().forEach(function (chord) {
            line = line.insertAt(chord.index + chord[0].length, '</span>');
            line = line.insertAt(chord.index, '<span class="chord">');
        });
        return line;
    }


    function insertNoteTag(line) {
        var note;
        var notes = [];
        while ((note = noteGRe.exec(line)) !== null) {
            notes.push(note);
        }
        notes.reverse().forEach(function (note) {
            line = line.insertAt(note.index + note[0].length, '</span>');
            line = line.insertAt(note.index, '<span class="note">');
        });
        return line;
    }


    function shiftKey(note, amount) {
        return legalNotes[circularIndex(legalNotes.indexOf(note), amount, N_KEYS)];
    }


    return {
        init: init,
        transpose: transpose
    }

})(jQuery);