show error when something other than an image is inserted

assets/css/main.less

@@ -467,7 +467,8 @@ body {
 
 		&.error {
 			p {
-				margin-bottom: 20px
+				margin-bottom: 20px;
+				line-height: 1.6em;
 			}
 		}
 

assets/js/appflow.coffee

@@ -36,20 +36,36 @@ appFlow = (pasteboard) ->
 				# An image has been inserted
 				$pasteboard.on "imageinserted.stateevents", (e, eventData) ->
 					$pasteboard.off ".stateevents"
+					$modalWindow.off "cancel"
 					setState ++state, image: eventData.image
 
 				# The image that the user is trying to insert is too large
-				$pasteboard.on "filetoolarge.stateevents", (e, eventData) ->
+				$pasteboard.on "filetoolarge.stateevents", (e) ->
 					pasteboard.modalWindow.show("error",
 						content: "The file size of the image you are trying to
 								  insert exceeds the current limit of 
 								  #{pasteboard.fileHandler.getFileSizeLimit() / (1024 * 1024)} MB. 
 								  <br><br>Please try another image."
 						showCancel: true
 					)
-					$modalWindow.on "cancel", () ->
-						$modalWindow.off "cancel"
-						pasteboard.modalWindow.hide()
+
+				# The user tried to insert something other than an image
+				$pasteboard.on "noimagefound.stateevents", (e, eventData) ->
+					content = "No image found"
+					if eventData.paste
+						content = "No image data was found in your clipboard,
+									copy an image first (or take a screenshot)."
+					else if eventData.drop
+						content = "The object you dragged in is not an image file."
+
+					pasteboard.modalWindow.show("error",
+						content: content
+						showCancel: true
+					)
+
+				$modalWindow.on "cancel", () ->
+					pasteboard.modalWindow.hide()
+
 
 			# State 3: User is looking at / editing the image
 			when states.editingImage

assets/js/copyandpaste.coffee

@@ -22,7 +22,7 @@ copyAndPaste = (pasteboard) ->
 					pasteboard.fileHandler.readFile item.getAsFile()
 					return
 
-			pasteboard.noImageError()
+			$(pasteboard).trigger "noimagefound", paste: true
 		else
 			setTimeout parsePaste, 1
 
@@ -35,7 +35,7 @@ copyAndPaste = (pasteboard) ->
 				pasteboard.fileHandler.readData child.src
 				return
 
-		pasteboard.noImageError()
+		$(pasteboard).trigger "noimagefound", paste: true
 
 	focusPasteArea = () ->
 		pasteArea.focus() 

assets/js/draganddrop.coffee

@@ -28,8 +28,7 @@ dragAndDrop = (pasteboard) ->
 				pasteboard.fileHandler.readFile file
 				return
 
-		pasteboard.noImageError()
-
+		$(pasteboard).trigger "noimagefound", drop: true
 
 	self = 
 		isSupported: () -> !!(Modernizr.draganddrop and pasteboard.fileHandler.isSupported())

assets/js/main.coffee

@@ -8,9 +8,7 @@ window.log = ->
 	if window.console
 		window.console.log.apply window.console, arguments
 
-pasteboard = 
-	noImageError: () ->
-		log "no images found"
+pasteboard = {}
 
 window.moduleLoader.loadAll(pasteboard)