function ytknsRequestJson(url, callback, method, data, headers, handleErr, upload) {
    if(!callback)
        callback = function(){};

    var xhr = new XMLHttpRequest;

    if(xhr.upload && upload) {
        xhr.upload.onloadstart = function(ev) { upload('loadstart', ev); };
        xhr.upload.onprogress = function(ev) { upload('progress', ev) };
        xhr.upload.onload = function(ev) { upload('load', ev); };
    }

    xhr.onreadystatechange = function() {
        if(xhr.readyState !== 4)
            return;

        var json = JSON.parse(xhr.responseText);

        if(json.err && !handleErr) {
            alert(json.err);
            callback([]);
        } else
            callback(json);
    };
    xhr.open(method || 'GET', url);

    if(headers && headers.length > 0)
        for(var i = 0; i < headers.length; i++)
            xhr.setRequestHeader(headers[i].name, headers[i].value);

    xhr.send(data || null);
}

function ytknsEditorLoadEffects(callback) {
    ytknsRequestJson('/zones/_effects', callback);
}

function ytknsLoadZoneInfo(zoneId, callback) {
    ytknsRequestJson('/zones/' + parseInt(zoneId).toString() + '.json', callback);
}

function ytknsLoadUploadInfo(uploadId, callback) {
    ytknsRequestJson('/uploads/' + uploadId.toString() + '.json', callback);
}

function ytknsCreateUrlString(set) {
    var parts = [];

    for(var i = 0; i < set.length; i++)
        parts.push(encodeURIComponent(set[i].name) + '=' + encodeURIComponent(set[i].value));

    return parts.join('&');
}
function ytknsCreateUrlStringPart(name, value) {
    return { 'name': name.toString(), 'value': (
        (typeof value).toLowerCase() === 'object'
            ? JSON.stringify(value)
            : value.toString()
    ) };
}

function ytknsZoneInfoToUrlString(zoneInfo) {
    return ytknsCreateUrlString(ytknsZoneInfoSerialise(zoneInfo, ytknsCreateUrlStringPart));
}
function ytknsZoneInfoSerialise(zoneInfo, callback) {
    var set = [];

    if(zoneInfo) {
        set.push(callback('zone_token', ytknsEditorToken || ''));
        set.push(callback('zone_id', zoneInfo.id));
        set.push(callback('zone_name', zoneInfo.name));
        set.push(callback('zone_title', zoneInfo.title));

        if(zoneInfo.effects && zoneInfo.effects.length > 0) {
            for(var i = 0; i < zoneInfo.effects.length; i++) {
                var format = 'zone_effect[%1][%2]'.replace('%1', zoneInfo.effects[i].type),
                    keys = Object.keys(zoneInfo.effects[i].values);

                if(keys.length < 1) {
                    set.push(callback(format.replace('%2', '_'), '_'));
                } else
                    for(var j = 0; j < keys.length; j++) {
                        var key = format.replace('%2', keys[j]);
                        set.push(callback(key, zoneInfo.effects[i].values[keys[j]] || ''));
                    }
            }
        }
    }

    return set;
}

function ytknsSaveZoneInfo(zoneInfo, callback) {
    if(!zoneInfo || !zoneInfo.id)
        return;

    ytknsRequestJson(
        '/zones/' + parseInt(zoneInfo.id).toString() + '.json',
        callback,
        'POST',
        ytknsZoneInfoToUrlString(zoneInfo),
        [{ name: 'Content-Type', value: 'application/x-www-form-urlencoded' }]
    );
}

function ytknsEditorPreview(zoneInfo) {
    var formElement = document.createElement('form');
    formElement.action = '/zones/_preview';
    formElement.method = 'post';
    formElement.target = '_blank';
    formElement.style.display = 'none';

    var elements = ytknsZoneInfoSerialise(zoneInfo, function(name, value) {
        var inputElement = document.createElement('input');
        inputElement.name = name;
        inputElement.type = 'hidden';
        inputElement.value = (
            (typeof value).toLowerCase() === 'object'
                ? JSON.stringify(value)
                : value.toString()
        );
        formElement.appendChild(inputElement);
    });

    document.body.appendChild(formElement);
    formElement.submit();
    formElement.parentNode.removeChild(formElement);
}

function ytknsEditorCreateUpload(file, callback, status) {
    var formData = new FormData;
    formData.append('upload_token', ytknsEditorUploadToken || '');
    formData.append('upload_file', file);

    ytknsRequestJson(
        '/uploads',
        callback,
        'POST',
        formData,
        null,
        true,
        status
    );
}

var ytknsZoneInfo = null,
    ytknsEditorToken = '',
    ytknsEditorUploadToken = '',
    ytknsEditorElemSidebar = null,
    ytknsEditorElemSidebarButtons = null,
    ytknsEditorElemSidebarEffects = null,
    ytknsEditorElemMain = null,
    ytknsEditorElemMainTitle = null,
    ytknsEditorElemMainContainer = null,
    ytknsEditorEffects = [],
    ytknsEditorIgnoreHashChange = false,
    ytknsEditorCleanExit = true;

function ytknsEditorChangeHash(hash) {
    ytknsEditorIgnoreHashChange = true;
    location.hash = hash;
}

function ytknsEditorBeforeUnload(ev) {
    if(!ytknsEditorCleanExit) {
        ev.preventDefault();
        ev.returnValue = '';
    }
}

function ytknsGetEffectInfoByType(type) {
    for(var i = 0; i < ytknsEditorEffects.length; i++)
        if(ytknsEditorEffects[i].type === type)
            return ytknsEditorEffects[i];
    return null;
}

function ytknsGetEffectValueByType(type) {
    if(ytknsZoneInfo === null || ytknsZoneInfo.effects === null || ytknsZoneInfo.effects.length < 1)
        return null;

    for(var i = 0; i < ytknsZoneInfo.effects.length; i++)
        if(ytknsZoneInfo.effects[i].type === type)
            return ytknsZoneInfo.effects[i];

    return null;
}
function ytknsRemoveEffectValueByType(type) {
    var info = ytknsGetEffectValueByType(type);

    if(!info) {
        alert('Tried to remove an effect that doesn\'t exist.');
        return;
    }

    var index = ytknsZoneInfo.effects.indexOf(info);

    if(index >= 0)
        ytknsZoneInfo.effects.splice(index, 1);

    ytknsEditorUpdateSidebarEffects();
}

function ytknsEditorFilePickerDoUpload(files, callback, status) {
    if(files.length < 1) {
        alert('No file selected.');
        return;
    }

    var file = files[0];

    ytknsEditorCreateUpload(file, function(resp) {
        if(resp.file) {
            ytknsLoadUploadInfo(resp.file, function(uploadInfo) {
                callback(uploadInfo);
            });
        } else if(resp.err) {
            alert(resp.err);
            if(status)
                status(-1, -1);
        }
    }, function(type, ev) {
        if(status)
            status(ev.loaded, ev.total);
    });
}

function ytknsEditorShowFilePicker(mimes, title, callback) {
    var container = document.createElement('div');
    container.classList.add('ye-applet-uploads');

    var progressBarContainer = document.createElement('div');
    progressBarContainer.classList.add('ye-applet-uploads-progress');
    progressBarContainer.classList.add('ye-applet-uploads-hidden');
    container.appendChild(progressBarContainer);

    var progressBar = document.createElement('progress');
    progressBar.min = 0;
    progressBar.max = 100;
    progressBar.value = 0;
    progressBar.classList.add('ye-applet-uploads-progress-bar');
    progressBarContainer.appendChild(progressBar);

    var dropZone = document.createElement('div'),
        dropZoneInner = document.createElement('div');
    dropZone.classList.add('ye-applet-uploads-dropzone');
    dropZoneInner.classList.add('ye-applet-uploads-dropzone-inner');
    dropZoneInner.textContent = 'Drop a file or click here!';
    dropZone.appendChild(dropZoneInner);
    container.appendChild(dropZone);

    var cancel = document.createElement('input');
    cancel.classList.add('ye-applet-uploads-cancel');
    cancel.type = 'button';
    cancel.value = 'Cancel';
    cancel.onclick = function() { callback(null); };
    container.appendChild(cancel);

    var doUpload = function(files) {
        dropZone.classList.add('ye-applet-uploads-hidden');
        cancel.classList.add('ye-applet-uploads-hidden');
        progressBarContainer.classList.remove('ye-applet-uploads-hidden');
        
        ytknsEditorFilePickerDoUpload(files, function(resp) {
            dropZone.classList.remove('ye-applet-uploads-hidden');
            cancel.classList.remove('ye-applet-uploads-hidden');
            progressBarContainer.classList.add('ye-applet-uploads-hidden');
            callback(resp);
        }, function(loaded, total) {
            if(loaded < 0 && total < 0) {
                dropZone.classList.remove('ye-applet-uploads-hidden');
                cancel.classList.remove('ye-applet-uploads-hidden');
                progressBarContainer.classList.add('ye-applet-uploads-hidden');
                return;
            }

            progressBar.value = Math.ceil((loaded / total) * 100);
        });
    };

    dropZone.onclick = function() {
        var selector = document.createElement('input');
        selector.type = 'file';
        selector.onchange = function() { doUpload(selector.files); };

        if(mimes)
            selector.accept = mimes.join(',');

        selector.click();
    };
    dropZone.ondragenter = function(ev) {
        ev.preventDefault();
        ev.stopPropagation();
        dropZone.classList.add('ye-applet-uploads-dropzone--active');
    };
    dropZone.ondragleave = function(ev) {
        ev.preventDefault();
        ev.stopPropagation();
        dropZone.classList.remove('ye-applet-uploads-dropzone--active');
    };
    dropZone.ondragover = function(ev) {
        ev.preventDefault();
        ev.stopPropagation();
        dropZone.classList.add('ye-applet-uploads-dropzone--active');
    };
    dropZone.ondrop = function(ev) {
        ev.preventDefault();
        ev.stopPropagation();
        dropZone.classList.remove('ye-applet-uploads-dropzone--active');
        doUpload(ev.dataTransfer.files);
    };

    ytknsEditorMainSetContainer(container, title || 'Upload File');
}

function ytknsLoadEffectEditor(effectInfo, effectValue) {
    ytknsEditorChangeHash(effectInfo.type);

    var editor = document.createElement('div');
    editor.classList.add('ye-applet-editor');

    if(effectInfo.props.length < 1) {
        var empty = document.createElement('div');
        editor.classList.add('ye-applet-editor--fill');
        empty.classList.add('ye-applet-editor-empty');
        empty.textContent = 'This effect has no properties.';
        editor.appendChild(empty);
    } else {
        var properties = document.createElement('div');
        properties.classList.add('ye-applet-editor-properties');
        editor.appendChild(properties);

        for(var i = 0; i < effectInfo.props.length; i++) {
            ytknsAddEffectEditorProperty(
                properties,
                effectInfo, effectValue, effectInfo.props[i],
                function() { ytknsLoadEffectEditor(effectInfo, effectValue); } // there's gotta be a better way
            );
        }
    }

    ytknsEditorMainSetContainer(editor, effectInfo.name);
}
function ytknsAddEffectEditorProperty(listContainer, effectInfo, effectValue, propInfo, redraw) {
    var container = document.createElement('div');
    container.classList.add('ye-applet-editor-properties-property');
    listContainer.appendChild(container);

    var propTitle = document.createElement('div');
    propTitle.classList.add('ye-applet-editor-properties-property-title');
    propTitle.textContent = propInfo.title;
    container.appendChild(propTitle);

    var propWrap = document.createElement('div');
    propWrap.classList.add('ye-applet-editor-properties-property-wrap');
    container.appendChild(propWrap);

    switch(propInfo.type.name) {
        case 'upload':
            var propUpload = document.createElement('div');
            propUpload.classList.add('ye-applet-editor-properties-property-upload');
            propWrap.appendChild(propUpload);

            var propUploadId = document.createElement('div');
            propUploadId.classList.add('ye-applet-editor-properties-property-upload-id');
            propUploadId.textContent = effectValue.values[propInfo.name] || '(none)';
            propUpload.appendChild(propUploadId);

            var propUploadSelect = document.createElement('div');
            propUploadSelect.classList.add('ye-applet-editor-properties-property-upload-select');
            propUploadSelect.title = 'Upload file';
            propUploadSelect.onclick = function() {
                ytknsEditorShowFilePicker(propInfo.type.allowed || [], ('Selecting ' + propInfo.title + ' for ' + effectInfo.name), function(uploadInfo) {
                    if(uploadInfo)
                        effectValue.values[propInfo.name] = uploadInfo.id || null;

                    redraw();
                });
            };
            propUpload.appendChild(propUploadSelect);
            break;

        case 'bool':
            var propBool = document.createElement('label');
            propBool.classList.add('ye-applet-editor-properties-property-bool');
            propWrap.appendChild(propBool);

            var propBoolToggle = document.createElement('input');
            propBoolToggle.classList.add('ye-applet-editor-properties-property-bool-toggle');
            propBoolToggle.type = 'checkbox';
            propBoolToggle.checked = (typeof effectValue.values[propInfo.name]).toLowerCase() === 'undefined'
                ? (propInfo.default || false)
                : effectValue.values[propInfo.name];
            propBoolToggle.onchange = function() {
                effectValue.values[propInfo.name] = propBoolToggle.checked;
                redraw();
            };
            propBool.appendChild(propBoolToggle);
            break;

        case 'int':
        case 'float':
            var propInt = document.createElement('label');
            propInt.classList.add('ye-applet-editor-properties-property-int');
            propWrap.appendChild(propInt);

            var propIntInput = document.createElement('input');
            propIntInput.classList.add('ye-applet-editor-properties-property-int-input');
            propIntInput.type = 'number';
            
            if(propInfo.min)
                propIntInput.min = propInfo.min;
            if(propInfo.max)
                propIntInput.max = propInfo.max;
            if(propInfo.type.name === 'float')
                propIntInput.step = 0.01;

            propIntInput.value = effectValue.values[propInfo.name] || propInfo.default || 0;
            propIntInput.onchange = function() {
                effectValue.values[propInfo.name] = propInfo.type.name === 'int' ? parseInt(propIntInput.value) : parseFloat(propIntInput.value);
                redraw();
            };
            propInt.appendChild(propIntInput);
            break;

        case 'select':
            var propSelect = document.createElement('label');
            propSelect.classList.add('ye-applet-editor-properties-property-select');
            propWrap.appendChild(propSelect);

            var propSelectInput = document.createElement('select');
            propSelectInput.classList.add('ye-applet-editor-properties-property-select-input');
            propSelectInput.onchange = function() {
                effectValue.values[propInfo.name] = propSelectInput.value;
                redraw();
            };
            propSelect.appendChild(propSelectInput);

            var propSelectOptionsKeys = Object.keys(propInfo.type.options),
                propSelectOptionsValues = Object.values(propInfo.type.options);

            for(var i = 0; i < propSelectOptionsKeys.length; i++) {
                var propSelectOption = document.createElement('option');
                propSelectOption.value = propSelectOptionsKeys[i];
                propSelectOption.textContent = propSelectOptionsValues[i];
                propSelectOption.selected = (effectValue.values[propInfo.name] || propInfo.default) === propSelectOptionsKeys[i];
                propSelectInput.appendChild(propSelectOption);
            }
            break;

        case 'colour':
            var propColour = document.createElement('label');
            propColour.classList.add('ye-applet-editor-properties-property-colour');
            propWrap.appendChild(propColour);

            var propColourInput = document.createElement('input');
            propColourInput.type = 'color';
            propColourInput.value = '#' + (effectValue.values[propInfo.name] || 0).toString(16).padStart(6, '0');
            propColourInput.classList.add('ye-applet-editor-properties-property-colour-input');
            propColourInput.onchange = function() {
                effectValue.values[propInfo.name] = parseInt(propColourInput.value.substring(1), 16);
                redraw();
            };
            propColour.appendChild(propColourInput);
            break;

        case 'string':
            var propString = document.createElement('label');
            propString.classList.add('ye-applet-editor-properties-property-string');
            propWrap.appendChild(propString);

            var propStringInput = document.createElement('input');
            propStringInput.type = 'text';

            if(propInfo.type.min)
                propStringInput.minLength = propInfo.type.min;
            if(propInfo.type.max)
                propStringInput.maxLength = propInfo.type.max;

            propStringInput.value = effectValue.values[propInfo.name] || '';
            propStringInput.classList.add('ye-applet-editor-properties-property-string-input');
            propStringInput.onchange = function() {
                effectValue.values[propInfo.name] = propStringInput.value;
                redraw();
            };
            propString.appendChild(propStringInput);
            break;

        case 'gradient':
            if(!effectValue.values[propInfo.name])
                effectValue.values[propInfo.name] = {};

            var propGrad = document.createElement('div');
            propGrad.classList.add('ye-applet-editor-properties-property-gradient');
            propWrap.appendChild(propGrad);

            var propGradPreview = document.createElement('div');
            propGradPreview.classList.add('ye-applet-editor-properties-property-gradient-preview');
            propGrad.appendChild(propGradPreview);

            var propGradDirection = document.createElement('div');
            propGradDirection.classList.add('ye-applet-editor-properties-property-gradient-direction');
            propGrad.appendChild(propGradDirection);

            var propGradDirectionCircle = document.createElement('div');
            propGradDirectionCircle.classList.add('ye-applet-editor-properties-property-gradient-direction-circle');
            propGradDirection.appendChild(propGradDirectionCircle);

            var propGradDirectionCircleValue = document.createElement('div');
            propGradDirectionCircleValue.classList.add('ye-applet-editor-properties-property-gradient-direction-circle-value');
            propGradDirectionCircle.appendChild(propGradDirectionCircleValue);

            var propGradDirectionCircleIndicator = document.createElement('div');
            propGradDirectionCircleIndicator.classList.add('ye-applet-editor-properties-property-gradient-direction-circle-indicator');
            propGradDirectionCircleValue.appendChild(propGradDirectionCircleIndicator);

            var propGradDirectionValue = document.createElement('input');
            propGradDirectionValue.classList.add('ye-applet-editor-properties-property-gradient-direction-input');
            propGradDirectionValue.type = 'number';
            propGradDirectionValue.min = 0;
            propGradDirectionValue.max = 359;
            propGradDirectionValue.value = 0;
            propGradDirection.appendChild(propGradDirectionValue);

            var propGradRedrawPreview = function() {
                propGradPreview.style.backgroundImage = ytknsEditorGradientCSS(effectValue.values[propInfo.name]);
            };

            var propGradDirectionSet = function(val) {
                val = parseInt(val);
                effectValue.values[propInfo.name].d = val;
                if(propGradDirectionValue.value != val)
                    propGradDirectionValue.value = val;
                propGradDirectionCircleValue.style.transform = 'rotate(' + val + 'deg)';
                propGradRedrawPreview();
            };

            propGradDirectionSet(effectValue.values[propInfo.name].d || 0);

            propGradDirectionValue.onchange = function() {
                propGradDirectionSet(propGradDirectionValue.value);
            };

            var propGradDirectionCircleMouseEvent = function(ev) {
                if((ev.buttons & 1) < 1)
                    return;

                var rect = ev.target.getBoundingClientRect(),
                    y = ev.layerY - (rect.height / 2),
                    x = ev.layerX - (rect.width / 2),
                    deg = Math.atan2(x, y) * 180 / Math.PI,
                    val = 180 - parseInt(deg);

                propGradDirectionSet(val);
            };

            propGradDirectionCircle.onmousedown = propGradDirectionCircleMouseEvent;
            propGradDirectionCircle.onmousemove = propGradDirectionCircleMouseEvent;

            var propGradPoints = document.createElement('div');
            propGradPoints.classList.add('ye-applet-editor-properties-property-gradient-points');
            propGrad.appendChild(propGradPoints);

            var propGradPointAdd = function(point) {
                if(!point)
                    point = {};
                if((typeof point.c).toLowerCase() === 'undefined')
                    point.c = parseInt(0xFFFFFF * Math.random());
                if((typeof point.o).toLowerCase() === 'undefined')
                    point.o = parseInt(100 * Math.random());

                var propGradPoint = document.createElement('div');
                propGradPoint.classList.add('ye-applet-editor-properties-property-gradient-points-point');
                propGradPoints.appendChild(propGradPoint);

                var propGradPointActions = document.createElement('div');
                propGradPointActions.classList.add('ye-applet-editor-properties-property-gradient-points-point-actions');
                propGradPoint.appendChild(propGradPointActions);

                var propGradPointActionsAdd = function(name, title, action) {
                    var propGradPointAction = document.createElement('div');
                    propGradPointAction.classList.add('ye-applet-editor-properties-property-gradient-points-point-actions-action');
                    propGradPointAction.classList.add('ye-applet-editor-properties-property-gradient-points-point-actions-action--' + name);
                    propGradPointAction.title = title;
                    propGradPointAction.onclick = function() { if(action) action(); };
                    propGradPointActions.appendChild(propGradPointAction);
                };

                propGradPointActionsAdd('delete', 'Delete', function() {
                    var index = effectValue.values[propInfo.name].p.indexOf(point);
                    if(index < 0)
                        return;
                    effectValue.values[propInfo.name].p.splice(index, 1);
                    propGradPoints.removeChild(propGradPoint);
                    propGradRedrawPreview();
                });

                var propGradPointColour = document.createElement('label');
                propGradPointColour.classList.add('ye-applet-editor-properties-property-gradient-points-point-colour');
                propGradPoint.appendChild(propGradPointColour);
                
                var propGradPointColourValue = document.createElement('input');
                propGradPointColourValue.type = 'color';
                propGradPointColourValue.value = '#' + point.c.toString(16).padStart(6, '0');
                propGradPointColourValue.classList.add('ye-applet-editor-properties-property-gradient-points-point-colour-value');
                propGradPointColourValue.onchange = function() {
                    point.c = parseInt(propGradPointColourValue.value.substring(1), 16);
                    propGradPointColour.style.backgroundColor = propGradPointColourValue.value;
                    propGradRedrawPreview();
                };
                propGradPointColour.appendChild(propGradPointColourValue);
                propGradPointColour.style.backgroundColor = propGradPointColourValue.value;

                var propGradPointOffset = document.createElement('input');
                propGradPointOffset.type = 'range';
                propGradPointOffset.classList.add('ye-applet-editor-properties-property-gradient-points-point-offset-range');
                propGradPointOffset.value = 0;
                propGradPointOffset.min = 0;
                propGradPointOffset.max = 100;
                propGradPoint.appendChild(propGradPointOffset);

                var propGradPointOffsetNum = document.createElement('input');
                propGradPointOffsetNum.type = 'number';
                propGradPointOffsetNum.classList.add('ye-applet-editor-properties-property-gradient-points-point-offset-numeric');
                propGradPointOffsetNum.value = 0;
                propGradPointOffsetNum.min = 0;
                propGradPointOffsetNum.max = 100;
                propGradPoint.appendChild(propGradPointOffsetNum);

                var propGradPointOffsetIsSetting = false,
                    propGradPointOffsetSet = function(val) {
                        if(propGradPointOffsetIsSetting)
                            return;
                        propGradPointOffsetIsSetting = true;

                        val = parseInt(val);
                        propGradPointOffset.value = propGradPointOffsetNum.value = point.o = val;
                        propGradRedrawPreview();

                        propGradPointOffsetIsSetting = false;
                    };

                propGradPointOffsetSet(point.o);
                propGradPointOffset.onchange = function() {
                    propGradPointOffsetSet(propGradPointOffset.value);
                };
                propGradPointOffsetNum.onchange = function() {
                    propGradPointOffsetSet(propGradPointOffsetNum.value);
                };
            };

            var propGradPointAddButton = document.createElement('button');
            propGradPointAddButton.classList.add('ye-applet-editor-properties-property-gradient-points-add');
            propGradPointAddButton.onclick = function() {
                var point = {};
                if(!effectValue.values[propInfo.name].p)
                    effectValue.values[propInfo.name].p = [];
                effectValue.values[propInfo.name].p.push(point);
                propGradPointAdd(point);
                propGradRedrawPreview();
            };
            propGradDirection.appendChild(propGradPointAddButton);

            var propGradPointAddButtonIcon = document.createElement('div');
            propGradPointAddButtonIcon.classList.add('ye-applet-editor-properties-property-gradient-points-add-icon');
            propGradPointAddButton.appendChild(propGradPointAddButtonIcon);

            var propGradPointAddButtonText = document.createElement('div');
            propGradPointAddButtonText.classList.add('ye-applet-editor-properties-property-gradient-points-add-text');
            propGradPointAddButtonText.textContent = 'Add gradient point';
            propGradPointAddButton.appendChild(propGradPointAddButtonText);

            if(effectValue.values[propInfo.name].p)
                for(var i = 0; i < effectValue.values[propInfo.name].p.length; i++)
                    propGradPointAdd(effectValue.values[propInfo.name].p[i]);
            break;

        default:
            var propNone = document.createElement('div');
            propNone.classList.add('ye-applet-editor-properties-property-none');
            propNone.textContent = 'There is no handler available for this property type.';
            propWrap.appendChild(propNone);
            break;
    }

    var propDefault = document.createElement('div');
    propDefault.classList.add('ye-applet-editor-properties-property-reset');
    propDefault.title = 'Reset';
    propDefault.onclick = function() {
        effectValue.values[propInfo.name] = propInfo.default;
        redraw();
    };
    propWrap.appendChild(propDefault);
}

function ytknsEditorGradientCSS(obj) {
    var str = 'linear-gradient(' + (obj.d || 0).toString() + 'deg, ',
        points = [];

    if(obj.p)
        for(var i = 0; i < obj.p.length; i++)
            points.push('#' + (obj.p[i].c || 0).toString(16).padStart(6, '0') + ' ' + (obj.p[i].o || 0).toString() + '%');

    return str + points.join(', ') + ')';
}

function ytknsEditorAddSidebarButton(className, title, callback) {
    var button = document.createElement('div');
    button.classList.add('ye-sidebar-buttons-button');
    button.classList.add('ye-sidebar-buttons-button--' + className);
    button.title = title;
    button.onclick = callback;
    ytknsEditorElemSidebarButtons.appendChild(button);
}
function ytknsEditorAddSidebarButtonSeparator() {
    var separator = document.createElement('div');
    separator.classList.add('ye-sidebar-buttons-separator');
    ytknsEditorElemSidebarButtons.appendChild(separator);
}

function ytknsEditorAddSidebarEffect(effectValue) {
    var effectInfo = ytknsGetEffectInfoByType(effectValue.type);

    if(!effectInfo) {
        alert('Attempted to add unregistered effect.');
        return;
    }

    var effect = document.createElement('div');
    effect.classList.add('ye-sidebar-effects-effect');
    ytknsEditorElemSidebarEffects.appendChild(effect);

    var effectName = document.createElement('div');
    effectName.classList.add('ye-sidebar-effects-effect-name');
    effectName.textContent = effectInfo.name;
    effect.appendChild(effectName);

    var effectActions = document.createElement('div');
    effectActions.classList.add('ye-sidebar-effects-effect-actions');
    effect.appendChild(effectActions);

    ytknsEditorAddSidebarEffectAction(effectActions, 'edit', 'Edit Effect', function() {
        ytknsLoadEffectEditor(effectInfo, effectValue);
    });
    ytknsEditorAddSidebarEffectAction(effectActions, 'delete', 'Delete Effect', function() {
        var previous = ytknsEditorMainClone();
        ytknsEditorMainShowEffectDeleteConfirm(effectInfo, function(accept) {
            if(accept) {
                ytknsRemoveEffectValueByType(effectValue.type);
                ytknsEditorMainShowWelcome();
            } else {
                ytknsEditorMainRestore(previous);
            }
        });
    });
}
function ytknsEditorMainShowEffectDeleteConfirm(effectInfo, callback) {
    var confirmation = document.createElement('div'),
        text = confirmation.appendChild(document.createElement('div')),
        actions = confirmation.appendChild(document.createElement('div'));
    confirmation.classList.add('ye-main-effect-delete-confirm');
    text.classList.add('ye-main-effect-delete-confirm-text');
    text.textContent = 'Are you sure you want to delete "' + effectInfo.name + '"?';
    actions.classList.add('ye-main-effect-delete-confirm-actions');

    var accept = document.createElement('div');
    accept.classList.add('ye-main-effect-delete-confirm-actions-action');
    accept.classList.add('ye-main-effect-delete-confirm-actions-action--accept');
    accept.textContent = 'Yes';
    accept.onclick = function() { callback(true); };
    actions.appendChild(accept);
    
    var deny = document.createElement('div');
    deny.classList.add('ye-main-effect-delete-confirm-actions-action');
    deny.classList.add('ye-main-effect-delete-confirm-actions-action--deny');
    deny.textContent = 'No';
    deny.onclick = function() { callback(false); };
    actions.appendChild(deny);

    ytknsEditorMainSetContainer(confirmation, 'Delete effect');
}
function ytknsEditorAddSidebarEffectAction(container, className, title, callback) {
    var action = document.createElement('div');
    action.classList.add('ye-sidebar-effects-effect-actions-action');
    action.classList.add('ye-sidebar-effects-effect-actions-action--' + className);
    action.title = title;
    action.onclick = callback;
    container.appendChild(action);
}
function ytknsEditorUpdateSidebarEffects() {
    ytknsEditorElemSidebarEffects.innerHTML = '';

    if(ytknsZoneInfo == null || ytknsZoneInfo.effects == null || ytknsZoneInfo.effects.length < 1) {
        var nothing = document.createElement('div');
        nothing.classList.add('ye-sidebar-effects-empty');
        nothing.textContent = 'You have not added any effects yet.';
        ytknsEditorElemSidebarEffects.appendChild(nothing);
    } else {
        for(var i = 0; i < ytknsZoneInfo.effects.length; i++)
            ytknsEditorAddSidebarEffect(ytknsZoneInfo.effects[i]);
    }
}

function ytknsShowDetailsEdit() {
    ytknsEditorChangeHash('details');

    var container = document.createElement('div');
    container.classList.add('ye-main-details');

    var fieldsElem = document.createElement('div');
    fieldsElem.classList.add('ye-main-details-fields');
    container.appendChild(fieldsElem);

    var fields = [
        { name: 'Zone ID', value: ytknsZoneInfo.id },
        { name: 'Subdomain', value: ytknsZoneInfo.name, suffix: '.' + location.host },
        { name: 'Title', value: ytknsZoneInfo.title, max: 255, edit: function(val) {
            ytknsZoneInfo.title = val;
        } },
    ];

    for(var i = 0; i < fields.length; i++) {
        var field = fields[i],
            fieldElem = document.createElement('div');
        fieldElem.classList.add('ye-main-details-fields-field');

        var fieldName = document.createElement('div');
        fieldName.classList.add('ye-main-details-fields-field-name');
        fieldName.textContent = field.name + ':';
        fieldElem.appendChild(fieldName);

        var fieldWrap = document.createElement('div');
        fieldWrap.classList.add('ye-main-details-fields-field-wrap');
        fieldElem.appendChild(fieldWrap);

        var fieldInput = document.createElement('input');
        fieldInput.classList.add('ye-main-details-fields-field-input');
        fieldInput.type = 'text';
        fieldInput.value = field.value;

        if(field.max)
            fieldInput.maxLength = field.max;

        if(field.edit) {
            var onedit = field.edit;
            fieldInput.onchange = function(ev) {
                onedit(ev.target.value);
            };
        } else {
            fieldInput.readOnly = true;
            fieldElem.classList.add('ye-main-details-fields-field--readonly');
        }

        fieldWrap.appendChild(fieldInput);

        if(field.suffix)
            fieldWrap.appendChild(document.createTextNode(field.suffix));

        fieldsElem.appendChild(fieldElem);
    }

    ytknsEditorMainSetContainer(container, 'Zone information');
}

function ytknsEditorMainGetTitle() {
    return ytknsEditorElemMainTitle.textContent;
}
function ytknsEditorMainSetTitle(title) {
    ytknsEditorElemMainTitle.textContent = title;
}
function ytknsEditorMainGetContainer() {
    return ytknsEditorElemMainContainer.firstChild;
}
function ytknsEditorMainSetContainer(child, title) {
    if(title)
        ytknsEditorMainSetTitle(title);

    ytknsEditorElemMainContainer.innerHTML = '';
    ytknsEditorElemMainContainer.appendChild(child);
}
function ytknsEditorMainClone() {
    return {
        'title': ytknsEditorMainGetTitle(),
        'content': ytknsEditorMainGetContainer().cloneNode(true),
    };
}
function ytknsEditorMainRestore(clone) {
    ytknsEditorMainSetContainer(clone.content, clone.title);
}

function ytknsEditorMainShowWelcome() {
    var welcome = document.createElement('div');
    welcome.classList.add('ye-main-welcome');

    var welcomeH1 = document.createElement('h1');
    welcomeH1.classList.add('ye-main-welcome-h1');
    welcomeH1.textContent = 'Welcome!';
    welcome.appendChild(welcomeH1);

    var welcomeP = document.createElement('p');
    welcomeP.classList.add('ye-main-welcome-p');
    welcomeP.textContent = 'Select a tool in the sidebar to get started.';
    welcome.appendChild(welcomeP);

    ytknsEditorMainSetContainer(welcome, 'Welcome to the YTKNS Editor');
}

function ytknsEditorMainShowEffectList() {
    ytknsEditorChangeHash('add');

    var container = document.createElement('div');
    container.classList.add('ye-applet-effects');

    var effects = document.createElement('div');
    effects.classList.add('ye-applet-effects-list');
    container.appendChild(effects);

    for(var i = 0; i < ytknsEditorEffects.length; i++) {
        var effectInfo = ytknsEditorEffects[i],
            effectValue = ytknsGetEffectValueByType(effectInfo.type),
            effectElement = document.createElement('div'),
            effectUsed = effectValue !== null;
        effectElement.classList.add('ye-applet-effects-list-item');

        if(effectUsed)
            effectElement.classList.add('ye-applet-effects-list-item--used');

        var effectName = document.createElement('div');
        effectName.classList.add('ye-applet-effects-list-item-name');
        effectName.textContent = effectInfo.name;
        effectElement.appendChild(effectName);

        var effectActions = document.createElement('div');
        effectActions.classList.add('ye-applet-effects-list-item-actions');
        effectElement.appendChild(effectActions);

        if(!effectUsed) {
            var effectActionAdd = document.createElement('div');
            effectActionAdd.classList.add('ye-applet-effects-list-item-actions-action');
            effectActionAdd.classList.add('ye-applet-effects-list-item-actions-action--add');
            effectActionAdd.title = 'Add Effect';
            (function() { // javascript is very cool and good
                var effectInfoCopy = effectInfo;
                effectActionAdd.onclick = function() {
                    var effectValueNew = ytknsEditorAddNewEffect(effectInfoCopy);
                    ytknsEditorUpdateSidebarEffects();
                    ytknsLoadEffectEditor(effectInfoCopy, effectValueNew);
                };
            })();
            effectActions.appendChild(effectActionAdd);
        }

        effects.appendChild(effectElement);
    }

    ytknsEditorMainSetContainer(container, 'Available effects');
}

function ytknsEditorAddNewEffect(effectInfo) {
    var effectValue = {
        type: effectInfo.type,
        values: {},
    };

    for(var i = 0; i < effectInfo.props.length; i++) {
        var propInfo = effectInfo.props[i];
        effectValue.values[propInfo.name] = propInfo.default || '';
    }

    ytknsZoneInfo.effects.push(effectValue);

    return effectValue;
}

function ytknsEditorConfirmReloadZoneInfo(zoneId) {
    if(confirm('Are you sure you want to undo any changes you\'ve made?'))
        ytknsEditorReloadZoneInfo(zoneId);
}
function ytknsEditorReloadZoneInfo(zoneId, onComplete) {
    ytknsEditorChangeHash('');
    ytknsEditorMainShowWelcome();

    ytknsEditorLoadEffects(function(effects) {
        ytknsEditorEffects = effects;

        ytknsLoadZoneInfo(zoneId, function(zoneInfo) {
            ytknsZoneInfo = zoneInfo;
            ytknsEditorUpdateSidebarEffects();

            if(onComplete)
                onComplete();
        });
    });
}

function ytknsEditorSwitchString(str) {
    switch(str) {
        case '':
            ytknsEditorMainShowWelcome();
            break;

        case 'add':
            ytknsEditorMainShowEffectList();
            break;

        case 'details':
            ytknsShowDetailsEdit();
            break;

        default:
            var openEffectInfo = ytknsGetEffectInfoByType(str);

            if(openEffectInfo) {
                var openEffectValue = ytknsGetEffectValueByType(str);
                ytknsLoadEffectEditor(openEffectInfo, openEffectValue);
            }
            break;
    }
}

function ytknsEditorHashChange(ev) {
    if(!ytknsEditorIgnoreHashChange)
        ytknsEditorSwitchString(location.hash.substring(1));

    ytknsEditorIgnoreHashChange = false;
}

function ytknsEditorMain(container, zoneId, editorToken, uploadToken) {
    if(navigator.userAgent.match(/mobile/gi) && !confirm("The editor is not designed to be used on phones whatsoever.\r\nHit OK to continue anyway or cancel to whereever you came from.")) {
        history.go(-1);
        return;
    }

    window.onhashchange = ytknsEditorHashChange;
    window.onbeforeunload = ytknsEditorBeforeUnload;
    ytknsEditorToken = editorToken;
    ytknsEditorUploadToken = uploadToken;

    container.innerHTML = '';
    container.classList.add('ye');

    ytknsEditorElemSidebar = container.appendChild(document.createElement('div'));
    ytknsEditorElemSidebar.classList.add('ye-sidebar');

    ytknsEditorElemSidebarButtons = ytknsEditorElemSidebar.appendChild(document.createElement('div'));
    ytknsEditorElemSidebarButtons.classList.add('ye-sidebar-buttons');

    ytknsEditorAddSidebarButton('save', 'Save', function() {
        ytknsSaveZoneInfo(ytknsZoneInfo, function(res) {
            if(res.msg)
                alert(res.msg);
        });
    });
    ytknsEditorAddSidebarButton('cancel', 'Cancel', function() { location.assign('/zones?f=my'); });
    ytknsEditorAddSidebarButton('reset', 'Undo Changes', function() { ytknsEditorConfirmReloadZoneInfo(zoneId); });
    ytknsEditorAddSidebarButton('edit', 'Edit Details', function() { ytknsShowDetailsEdit(); });
    ytknsEditorAddSidebarButtonSeparator();
    ytknsEditorAddSidebarButton('preview', 'Show Preview', function() { ytknsEditorPreview(ytknsZoneInfo); });
    ytknsEditorAddSidebarButton('live', 'View Live', function() { window.open('//%1.%2'.replace('%2', location.host).replace('%1', ytknsZoneInfo.name)); });
    ytknsEditorAddSidebarButtonSeparator();
    ytknsEditorAddSidebarButton('add', 'Add Effect', function() { ytknsEditorMainShowEffectList(); });

    ytknsEditorElemSidebarEffects = ytknsEditorElemSidebar.appendChild(document.createElement('div'));
    ytknsEditorElemSidebarEffects.classList.add('ye-sidebar-effects');
    ytknsEditorUpdateSidebarEffects();

    ytknsEditorElemMain = container.appendChild(document.createElement('div'));
    ytknsEditorElemMain.classList.add('ye-main');

    ytknsEditorElemMainTitle = ytknsEditorElemMain.appendChild(document.createElement('div'));
    ytknsEditorElemMainTitle.classList.add('ye-main-title');

    ytknsEditorElemMainContainer = ytknsEditorElemMain.appendChild(document.createElement('div'));
    ytknsEditorElemMainContainer.classList.add('ye-main-container');

    var goToEditor = location.hash.substring(1);

    ytknsEditorReloadZoneInfo(zoneId, function() {
        ytknsEditorSwitchString(goToEditor);
    });
}