improved crop features

templates/index.html

@@ -543,6 +543,9 @@
                 <!-- Crop Controls -->
                 <div class="form-group">
                     <label>✂️ Crop Video</label>
+                    <p style="font-size: 0.9em; color: #6c757d; margin-bottom: 10px;">
+                        💡 Draw crop area on video above • Double-click corner handles to snap to edges
+                    </p>
                     <div class="crop-controls">
                         <div class="form-row">
                             <div>
@@ -753,6 +756,12 @@
                 scaleSlider.value = 100;
                 updateScaleDisplay();
                 
+                // Set max values for crop inputs
+                document.getElementById('crop-x').max = videoInfo.width;
+                document.getElementById('crop-y').max = videoInfo.height;
+                document.getElementById('crop-width').max = videoInfo.width;
+                document.getElementById('crop-height').max = videoInfo.height;
+
                 // Setup canvas for cropping
                 setupCropCanvas();
 
@@ -906,11 +915,41 @@
             isDraggingHandle = false;
             isDraggingBox = false;
             activeHandle = null;
+            cropCanvas.style.cursor = 'crosshair';
             
             // Keep crop mode active and canvas visible
             drawCropRect();
         });
         
+        // Handle mouse leaving canvas while dragging
+        cropCanvas.addEventListener('mouseleave', (e) => {
+            if (isDrawing || isDraggingHandle || isDraggingBox) {
+                // Finish the drag operation
+                updateFormFields();
+                isDrawing = false;
+                isDraggingHandle = false;
+                isDraggingBox = false;
+                activeHandle = null;
+                drawCropRect();
+            }
+        });
+        
+        // Double-click on handles to snap to edges
+        cropCanvas.addEventListener('dblclick', (e) => {
+            if (!cropMode || !cropRect) return;
+            
+            const rect = cropCanvas.getBoundingClientRect();
+            const mouseX = e.clientX - rect.left;
+            const mouseY = e.clientY - rect.top;
+            
+            const handle = getHandleAtPosition(mouseX, mouseY);
+            if (handle) {
+                snapHandleToEdge(handle);
+                updateFormFields();
+                drawCropRect();
+            }
+        });
+
         function drawCropRect() {
             clearCropCanvas();
             
@@ -1056,6 +1095,33 @@
             drawCropRect();
         }
         
+        function snapHandleToEdge(handle) {
+            if (!cropRect) return;
+            
+            switch (handle) {
+                case 'tl': // Top-left -> snap to top-left corner
+                    cropRect.width += cropRect.x; // Extend width by current x
+                    cropRect.height += cropRect.y; // Extend height by current y
+                    cropRect.x = 0;
+                    cropRect.y = 0;
+                    break;
+                case 'tr': // Top-right -> snap to top-right corner
+                    cropRect.width = cropCanvas.width - cropRect.x;
+                    cropRect.height += cropRect.y;
+                    cropRect.y = 0;
+                    break;
+                case 'bl': // Bottom-left -> snap to bottom-left corner
+                    cropRect.width += cropRect.x;
+                    cropRect.height = cropCanvas.height - cropRect.y;
+                    cropRect.x = 0;
+                    break;
+                case 'br': // Bottom-right -> snap to bottom-right corner
+                    cropRect.width = cropCanvas.width - cropRect.x;
+                    cropRect.height = cropCanvas.height - cropRect.y;
+                    break;
+            }
+        }
+        
         function updateFormFields() {
             if (!cropRect) return;