From be1509c027bcc935f3f3b7e1acfb66f0584e3378 Mon Sep 17 00:00:00 2001
From: Aries <urchinzhou@gmail.com>
Date: Fri, 27 Sep 2024 15:51:24 +0800
Subject: [PATCH] Support mouse drag for multiple selection, improve
 interactivity (#6823)

---
 frontend/src/metadata/constants/index.js      |   2 +
 .../metadata/views/gallery/gallery-main.js    | 101 ++++++++++++++++--
 frontend/src/metadata/views/gallery/index.css |   6 ++
 frontend/src/metadata/views/gallery/index.js  |  28 ++---
 4 files changed, 109 insertions(+), 28 deletions(-)

diff --git a/frontend/src/metadata/constants/index.js b/frontend/src/metadata/constants/index.js
index cb95954ca8..bb2cb6f625 100644
--- a/frontend/src/metadata/constants/index.js
+++ b/frontend/src/metadata/constants/index.js
@@ -125,6 +125,8 @@ export const GALLERY_ZOOM_GEAR_MIN = -2;
 
 export const GALLERY_ZOOM_GEAR_MAX = 2;
 
+export const GALLERY_IMAGE_GAP = 2;
+
 export const GALLERY_DATE_MODE = {
   YEAR: 'year',
   MONTH: 'month',
diff --git a/frontend/src/metadata/views/gallery/gallery-main.js b/frontend/src/metadata/views/gallery/gallery-main.js
index 4f4089975e..502c84d1de 100644
--- a/frontend/src/metadata/views/gallery/gallery-main.js
+++ b/frontend/src/metadata/views/gallery/gallery-main.js
@@ -1,14 +1,85 @@
-import React, { useCallback, useMemo, useRef } from 'react';
+import React, { useState, useCallback, useMemo, useRef } from 'react';
 import classnames from 'classnames';
 import PropTypes from 'prop-types';
 import EmptyTip from '../../../components/empty-tip';
 import { gettext } from '../../../utils/constants';
 
-const GalleryMain = ({ groups, overScan, columns, size, gap, selectedImages, onImageClick, onImageDoubleClick, onImageRightClick }) => {
+const GalleryMain = ({
+  groups,
+  overScan,
+  columns,
+  size,
+  gap,
+  selectedImages,
+  setSelectedImages,
+  onImageClick,
+  onImageDoubleClick,
+  onImageRightClick
+}) => {
+  const containerRef = useRef(null);
   const imageRef = useRef(null);
+  const animationFrameRef = useRef(null);
+
+  const [isSelecting, setIsSelecting] = useState(false);
+  const [selectionStart, setSelectionStart] = useState(null);
 
   const imageHeight = useMemo(() => size + gap, [size, gap]);
 
+  const handleMouseDown = useCallback((e) => {
+    if (e.button !== 0) return;
+    if (e.ctrlKey || e.metaKey || e.shiftKey) return;
+
+    setIsSelecting(true);
+    setSelectionStart({ x: e.clientX, y: e.clientY });
+    setSelectedImages([]);
+
+  }, [setSelectedImages]);
+
+  const handleMouseMove = useCallback((e) => {
+    if (!isSelecting) return;
+
+    if (animationFrameRef.current) {
+      cancelAnimationFrame(animationFrameRef.current);
+    }
+
+    animationFrameRef.current = requestAnimationFrame(() => {
+      e.preventDefault();
+      e.stopPropagation();
+
+      const selectionEnd = { x: e.clientX, y: e.clientY };
+      const selected = [];
+
+      groups.forEach(group => {
+        group.children.forEach((row) => {
+          row.children.forEach((img) => {
+            const imgElement = document.getElementById(img.id);
+            if (imgElement) {
+              const rect = imgElement.getBoundingClientRect();
+              if (
+                rect.left < Math.max(selectionStart.x, selectionEnd.x) &&
+            rect.right > Math.min(selectionStart.x, selectionEnd.x) &&
+            rect.top < Math.max(selectionStart.y, selectionEnd.y) &&
+            rect.bottom > Math.min(selectionStart.y, selectionEnd.y)
+              ) {
+                selected.push(img);
+              }
+            }
+          });
+        });
+      });
+
+      setSelectedImages(selected);
+    });
+  }, [groups, isSelecting, selectionStart, setSelectedImages]);
+
+  const handleMouseUp = useCallback((e) => {
+    if (e.button !== 0) return;
+
+    e.preventDefault();
+    e.stopPropagation();
+    setIsSelecting(false);
+  }, []);
+
   const renderDisplayGroup = useCallback((group) => {
     const { top: overScanTop, bottom: overScanBottom } = overScan;
     const { name, children, height, top, paddingTop } = group;
@@ -36,7 +107,12 @@ const GalleryMain = ({ groups, overScan, columns, size, gap, selectedImages, onI
     }
 
     return (
-      <div key={name} className="metadata-gallery-date-group w-100" style={{ height, paddingTop }}>
+      <div
+        key={name}
+        className="metadata-gallery-date-group"
+        style={{ height, paddingTop }}
+
+      >
         {childrenStartIndex === 0 && (<div className="metadata-gallery-date-tag">{name}</div>)}
         <div
           ref={imageRef}
@@ -53,6 +129,7 @@ const GalleryMain = ({ groups, overScan, columns, size, gap, selectedImages, onI
               return (
                 <div
                   key={img.src}
+                  id={img.id}
                   tabIndex={1}
                   className={classnames('metadata-gallery-image-item', {
                     'metadata-gallery-image-item-selected': isSelected,
@@ -62,7 +139,7 @@ const GalleryMain = ({ groups, overScan, columns, size, gap, selectedImages, onI
                   onDoubleClick={(e) => onImageDoubleClick(e, img)}
                   onContextMenu={(e) => onImageRightClick(e, img)}
                 >
-                  <img className="metadata-gallery-grid-image" src={img.src} alt={img.name} />
+                  <img className="metadata-gallery-grid-image" src={img.src} alt={img.name} draggable="false" />
                 </div>
               );
             });
@@ -76,9 +153,19 @@ const GalleryMain = ({ groups, overScan, columns, size, gap, selectedImages, onI
     return <EmptyTip text={gettext('No record')}/>;
   }
 
-  return groups.map((group, index) => {
-    return renderDisplayGroup(group, index);
-  });
+  return (
+    <div
+      ref={containerRef}
+      className='metadata-gallery-main'
+      onMouseDown={handleMouseDown}
+      onMouseMove={handleMouseMove}
+      onMouseUp={handleMouseUp}
+    >
+      {groups.map((group) => {
+        return renderDisplayGroup(group);
+      })}
+    </div>
+  );
 };
 
 GalleryMain.propTypes = {
diff --git a/frontend/src/metadata/views/gallery/index.css b/frontend/src/metadata/views/gallery/index.css
index 0cf8109d90..d9ae3515ad 100644
--- a/frontend/src/metadata/views/gallery/index.css
+++ b/frontend/src/metadata/views/gallery/index.css
@@ -11,6 +11,7 @@
 }
 
 .metadata-gallery-date-group {
+  width: 100%;
   position: relative;
 }
 
@@ -28,6 +29,10 @@
   user-select: none;
 }
 
+.metadata-gallery-main {
+  flex: 1;
+}
+
 .metadata-gallery-image-list {
   display: grid;
   gap: 2px;
@@ -52,6 +57,7 @@
   height: 100%;
   object-fit: cover;
   transition: transform 0.2s ease-in-out;
+  user-select: none;
 }
 
 .metadata-gallery-grid-image:hover {
diff --git a/frontend/src/metadata/views/gallery/index.js b/frontend/src/metadata/views/gallery/index.js
index aeb26ef9b6..f533d09600 100644
--- a/frontend/src/metadata/views/gallery/index.js
+++ b/frontend/src/metadata/views/gallery/index.js
@@ -12,12 +12,10 @@ import { useMetadataView } from '../../hooks/metadata-view';
 import { Utils } from '../../../utils/utils';
 import { getDateDisplayString } from '../../utils/cell';
 import { siteRoot, fileServerRoot, useGoFileserver, gettext, thumbnailSizeForGrid, thumbnailSizeForOriginal } from '../../../utils/constants';
-import { EVENT_BUS_TYPE, PER_LOAD_NUMBER, PRIVATE_COLUMN_KEY, GALLERY_DATE_MODE, DATE_TAG_HEIGHT } from '../../constants';
+import { EVENT_BUS_TYPE, PER_LOAD_NUMBER, PRIVATE_COLUMN_KEY, GALLERY_DATE_MODE, DATE_TAG_HEIGHT, GALLERY_IMAGE_GAP } from '../../constants';
 
 import './index.css';
 
-const IMAGE_GAP = 2;
-
 const Gallery = () => {
   const [isFirstLoading, setFirstLoading] = useState(true);
   const [isLoadingMore, setLoadingMore] = useState(false);
@@ -90,7 +88,7 @@ const Gallery = () => {
       }, []);
 
     let _groups = [];
-    const imageHeight = imageSize + IMAGE_GAP;
+    const imageHeight = imageSize + GALLERY_IMAGE_GAP;
     init.forEach((_init, index) => {
       const { children, ...__init } = _init;
       let top = 0;
@@ -160,7 +158,7 @@ const Gallery = () => {
       // Calculate initial overScan information
       const columns = 8 - gear;
       const imageSize = (offsetWidth - columns * 2 - 2) / columns;
-      setOverScan({ top: 0, bottom: clientHeight + (imageSize + IMAGE_GAP) * 2 });
+      setOverScan({ top: 0, bottom: clientHeight + (imageSize + GALLERY_IMAGE_GAP) * 2 });
     }
     setFirstLoading(false);
 
@@ -186,18 +184,6 @@ const Gallery = () => {
     };
   }, []);
 
-  useEffect(() => {
-    const handleClickOutside = (e) => {
-      if (containerRef.current && !containerRef.current.contains(e.target) || e.target.tagName.toLowerCase() !== 'img') {
-        setSelectedImages([]);
-      }
-    };
-    document.addEventListener('click', handleClickOutside);
-    return () => {
-      document.removeEventListener('click', handleClickOutside);
-    };
-  }, []);
-
   const handleScroll = useCallback(() => {
     if (!containerRef.current) return;
     const { scrollTop, scrollHeight, clientHeight } = containerRef.current;
@@ -207,8 +193,8 @@ const Gallery = () => {
       renderMoreTimer.current && clearTimeout(renderMoreTimer.current);
       renderMoreTimer.current = setTimeout(() => {
         const { scrollTop, clientHeight } = containerRef.current;
-        const overScanTop = Math.max(0, scrollTop - (imageSize + IMAGE_GAP) * 3);
-        const overScanBottom = scrollTop + clientHeight + (imageSize + IMAGE_GAP) * 3;
+        const overScanTop = Math.max(0, scrollTop - (imageSize + GALLERY_IMAGE_GAP) * 3);
+        const overScanBottom = scrollTop + clientHeight + (imageSize + GALLERY_IMAGE_GAP) * 3;
         setOverScan({ top: overScanTop, bottom: overScanBottom });
         renderMoreTimer.current = null;
       }, 200);
@@ -241,7 +227,6 @@ const Gallery = () => {
     setIsImagePopupOpen(true);
   }, [imageItems]);
 
-
   const handleRightClick = useCallback((event, image) => {
     event.preventDefault();
     const index = imageItems.findIndex(item => item.id === image.id);
@@ -333,8 +318,9 @@ const Gallery = () => {
               size={imageSize}
               columns={columns}
               overScan={overScan}
-              gap={IMAGE_GAP}
+              gap={GALLERY_IMAGE_GAP}
               selectedImages={selectedImages}
+              setSelectedImages={setSelectedImages}
               onImageClick={handleClick}
               onImageDoubleClick={handleDoubleClick}
               onImageRightClick={handleRightClick}