;(function() {
	"use strict";
	
	var getCurrentScriptPath = function () {
		// Determine current script path
		// @ref https://stackoverflow.com/a/26023176
		var scripts = document.querySelectorAll('script[src]');
		var currentScript = scripts[scripts.length - 1].src;
		var currentScriptChunks = currentScript.split('/');
		var currentScriptFile = currentScriptChunks[currentScriptChunks.length - 1];

		return currentScript.replace(currentScriptFile, '');
	};
	
	var loadScript = function(url, onLoad) {
		var script = document.createElement('script');
		script.onload = onLoad;
		script.src = url;
		document.head.appendChild(script);
	};
	
	var loadScripts = function(urls, onLoad) {
		// load sequentially
		var i = 0;
		var loadNext = function() {
			if (i === urls.length) {
				onLoad();
				return;
			}
			
			var url = urls[i];
			i += 1;
			loadScript(url, loadNext);
		};
		loadNext();
	};
		
    var formatBytes = function(bytes) {
		var k = 1024, m = (1024*1024), g = (1024*1024*1024);
		
        if (bytes < k) {
            return bytes + " B";
        } else if (bytes < m) {
            return (bytes / k).toFixed(1) + " KiB";
        } else if (bytes < g) {
            return (bytes / m).toFixed(1) + " MiB";
        } else {
            return (bytes / g).toFixed(1) + " GiB";
        }
    };
	
	// @ref https://stackoverflow.com/a/2117523
	var guid = function uuidv4() {
		return 'xxxxxxxx-xxxx-4xxx-yxxx-xxxxxxxxxxxx'.replace(/[xy]/g, function(c) {
			var r = Math.random() * 16 | 0, v = c == 'x' ? r : (r & 0x3 | 0x8);
			return v.toString(16);
		});
	};

	var initArea = function (elementSelector, onUploaded, onClose) {
		onUploaded = onUploaded || function () { };
		onClose = onClose || function () { };

		if ($(elementSelector).length != 1) {
			return; // should only find one element
		}
		var element = $(elementSelector)[0];

		// <input type="hidden" name="MAX_FILE_SIZE" value="` + ret.MaxUploadBytes + `" /> 

		// Create a new div for ourselves on top of the existing area
		$.get(contented.baseURL + "about", function (ret) {
			
			var extraText = "";
			if (ret.MaxUploadBytes > 0) {
				extraText = " (max " + formatBytes(ret.MaxUploadBytes) + ")";
			}

			$.get(contented.baseURL + "widget.html", function (widgetHtml) {

				var $f = $("<div>").html(widgetHtml);
				$f.find(".contented-extratext").text(extraText);

				// Tab buttons
				
				var hasSetupDrawingBoardYet = false;
				var setType = function (type) {
					$f.find(".contented-upload-type").removeClass("contented-upload-type-active");
					$f.find(".contented-upload-type[data-upload-type=" + type + "]").addClass("contented-upload-type-active");

					$f.find(".contented-upload-if").removeClass("contented-active");
					$f.find(".contented-if-" + type).addClass("contented-active");
					
					if (type == "drag") {
						enablePasteHandler();
					} else {
						disablePasteHandler();
					}
					
					if (type == "drawing" && !hasSetupDrawingBoardYet) {
						setupDrawingBoard();
						hasSetupDrawingBoardYet = true;
					}
				};

				$f.find(".contented-upload-type").click(function () {
					setType($(this).attr('data-upload-type'));
				});

				// Widget positioning

				var $element = $(element);
				var offset = $element.offset();

				$f.css({
					'position': 'absolute',
					'left': offset.left + "px",
					'top': offset.top + "px",
					'width': $element.width() + "px",
					'min-width': $element.width() + "px",
					'max-width': $element.width() + "px",
					'height': $element.height() + "px",
					'min-height': $element.height() + "px",
					'max-height': $element.height() + "px"
				});

				// Drag and drop support
				
				$f.find('.contented').on('dragover dragenter', function (e) {
					e.preventDefault();
					e.stopPropagation();
					$(this).addClass('is-dragging');
				});

				$f.find('.contented').on('dragleave dragend', function (e) {
					e.preventDefault();
					e.stopPropagation();
					$(this).removeClass('is-dragging');
				});

				$f.find('.contented').on('drop', function (e) {
					e.preventDefault();
					e.stopPropagation();
					handleUploadFrom(e.originalEvent.dataTransfer.files);
				});

				$f.find('.contented-file-upload').on('click', function(e) {
					e.preventDefault();
					e.stopPropagation();
					handleUploadFrom($(".contented-file-selector")[0].files);
				});

				// Pastebin
				
				$f.find('.contented-paste-upload').on('click', function(e) {
					e.preventDefault();
					e.stopPropagation();
					var blob = new Blob([$(".contented-if-paste textarea").val()], {type : 'text/plain'});
					handleUploadFrom([blob]);
				});

				// Ctrl+V uploads
				
				var pasteHandler = function(e) {
					e.preventDefault();
					e.stopPropagation();
					
					var items = (e.clipboardData || e.originalEvent.clipboardData).items;
					var items_length = items.length;
					var blobs = [];
					var handled = 0;
					var haveHandled = function() {
						handled += 1;
						if (handled == items_length) {
							
							if (blobs.length > 0) {
								handleUploadFrom( blobs );
							} else {
								// alert("Pasted 0 files");
							}
						}
					};
					
					for (var i = 0; i < items.length; ++i) {
						var item = items[i];
						var mimeType = item.type;
						if (item.kind === 'file') {
							blobs.push(item.getAsFile());
							haveHandled();
							
						} else if (item.kind === 'string') {
							item.getAsString(function(s) {
								blobs.push( new Blob([s], {type : mimeType}) );
								haveHandled();
							});
							
						} else {
							// file|string are the only supported types in
							// all browsers at the time of writing
							// Ignore future possibilities
							haveHandled();
						}
					}
				};
				var enablePasteHandler = function() {
					document.addEventListener('paste', pasteHandler);
				};
				var disablePasteHandler = function() {
					document.removeEventListener('paste', pasteHandler);
				};
				
				// Embed in DOM, load default area
				
				$("body").append($f);
				if (!contented.supportsDrop()) {
					setType('file');
				} else {
					setType('drag');
				}
				
				// Drawing board
				
				var setupDrawingBoard = function() {
					
					$("head").append(
						'<link rel="stylesheet" type="text/css" href="' + contented.baseURL + 'drawingboard-0.4.6.min.css">'
					);
					
					var db_id = "contented-drawing-area-" + guid();
					var $db = $("<div>").attr('id', db_id);
					
					DrawingBoard.Control.ContentedUpload = DrawingBoard.Control.extend({
						name: 'upload',

						initialize: function() {
							var $el = this.$el;
							
							$el.append('<button class="contented-drawingboard-upload">Upload</button>');
							$el.on('click', '.contented-drawingboard-upload', $.proxy(function(e) {
								e.preventDefault();
								e.stopPropagation();
								
								$el.prop('disabled', true);
								$el.text('Saving...');
								
								$db.find("canvas")[0].toBlob(function(theBlob) {
									handleUploadFrom([ theBlob ]);
								});
							}, this));
						}
					});
					
					$db.css({
						//'width': $f.find(".contented-content-area").width(),
						'height': $f.find(".contented-content-area").height(),
						'overflow': 'hidden'
					});
					
					$f.find(".contented-drawing-area").append($db);
					var db = new DrawingBoard.Board(db_id, {
						'controls': [
							'Color',
							'Size',
							'DrawingMode',
							'Navigation',
							'ContentedUpload'
						],
						'controlsPosition': 'center',
						'enlargeYourContainer': false,
						'webStorage': false,
						'droppable': false // don't mess with existing drop support
					});
					
				};

				// Close button
				
				var ourClose = function () {
					$f.remove(); // remove from dom
					disablePasteHandler();
					onClose(); // upstream close
				};
				$f.find(".contented-close").click(function () {
					ourClose();
				})

				// Progress bar
				
				var setProgressCaption = function(message) {
					$f.find(".contented-if-progress label").text(message);
				};
				var setProgressPercentage = function(frc) {
					$f.find(".contented-progress-element").css('width', (frc * 100) + "%");
				};

				// Common upload handler
				
				var handleUploadFrom = function(files) {

					setProgressCaption("Uploading, please wait...");
					setProgressPercentage(0);
					setType("progress");

					$f.find(".contented-upload-type-selector").hide();
					$f.find(".contented").removeClass('is-dragging');

					// Ajax uploader
					var ajaxData = new FormData();
					for (var i = 0; i < files.length; ++i) {
						ajaxData.append("f", files[i]);
					}

					// ajax request
					$.ajax({
						url: contented.baseURL + "upload",
						type: "POST",
						data: ajaxData,
						dataType: 'json', // response type
						cache: false,
						contentType: false,
						processData: false,
						xhr: function() {
							var xhr = $.ajaxSettings.xhr();
							xhr.upload.addEventListener(
								'progress',
								function(ev) {
									if (ev.lengthComputable) {
										setProgressCaption("Uploading (" + formatBytes(ev.loaded) + " / " + formatBytes(ev.total) + ")...");
										setProgressPercentage(ev.total == 0 ? 0 : ev.loaded / ev.total);
									}
								},
								false
							);
							return xhr;
						},
						complete: function () {
							setProgressPercentage(1);
						},
						success: function (data) {
							setProgressCaption("Upload completed successfully.");
							onUploaded(data);
							ourClose();
						},
						error: function () {
							setProgressCaption("Upload failed!");
						}
					});

				}
				
				// .

			});

		});

	};

	var afterScriptsLoaded = function() {		
			
		// Update fields in global variable
		contented.init = initArea;
		contented.loaded = true;
		
		// Call initArea for all pre-initialised elements
		for (var i = 0; i < contented.__preInit.length; ++i) {
			initArea(contented.__preInit[i][0], contented.__preInit[i][1], contented.__preInit[i][2]);
		}
	};

	var init = function() {

		var currentScriptPath = getCurrentScriptPath();
		var baseURL = currentScriptPath.replace('sdk.js', '');
		
		window.contented = {
			"loaded": false,
			
			"baseURL": baseURL,
			
			"__preInit": [],
			
			/**
			* initArea shows the contented upload widget over the top of a target DOM element.
			*
			* @param any        element       Drop target (string selector / DOMElement / jQuery)
			* @param Function   onUploaded    Called with an array of upload IDs
			* @param Function   onClose       Called when the widget is being destroyed
			*/
			"init": function(elementSelector, onUploaded, onClose) {
				contented.__preInit.push([elementSelector, onUploaded, onClose]);
			},
			
			/**
			* supportsDrop returns whether drag-and-drop is supported by this browser.
			*
			* @return bool
			*/
			"supportsDrop": function() {
				return ('ondrop' in window && 'FormData' in window && 'FileReader' in window);
			},
			
			"getPreviewURL": function(id) {
				return baseURL + "p/" + encodeURIComponent(id);
			},
			"getMultiPreviewURL": function(items) {
				return baseURL + "p/" + encodeURIComponent(items.join("-"));
			},
			"getDownloadURL": function(id) {
				return baseURL + "get/" + encodeURIComponent(id);
			},
			"getInfoJSONURL": function(id) {
				return baseURL + "info/" + encodeURIComponent(id);
			},
			"getThumbnailURL": function(thumbnailType, id) {
				return baseURL + "thumb/" + encodeURIComponent(thumbnailType) + "/" + encodeURIComponent(id);
			},
			"thumbnail": {
				"small_square": "s",
				"medium_square": "b",
				"medium": "t",
				"large": "m",
				"xlarge": "l",
				"xxlarge": "h"
			}
		};
	
		// Load scripts
		var needScripts = [];
		if (typeof jQuery === "undefined") {
			needScripts.push(contented.baseURL + "jquery-3.7.0.min.js");
		}
		if (typeof DrawingBoard === "undefined") {
			needScripts.push(contented.baseURL + "drawingboard-0.4.6.min.js");
		}
		
		loadScripts(needScripts, afterScriptsLoaded);
	};

	init();

})()