From b0034e7c8ecd9cd4f21548f5dc41102e4c8eeb72 Mon Sep 17 00:00:00 2001
From: Christian Ebert <bcc@phloxic.productions>
Date: Mon, 4 Dec 2023 00:08:27 +0100
Subject: [PATCH] feat: support multiple sprites and individual thumbnails

cf #57 for vjs6-7-compat
---
 README.md                | 34 ++++++++++++++++++++--------------
 package.json             |  2 +-
 src/plugin.js            | 10 ++++++++--
 src/sprite-thumbnails.js | 27 +++++++++++++++++++++------
 4 files changed, 50 insertions(+), 23 deletions(-)

diff --git a/README.md b/README.md
index 4c2c030..a30eb63 100644
--- a/README.md
+++ b/README.md
@@ -21,7 +21,7 @@
 
 # videojs-sprite-thumbnails
 
-Plugin to display thumbnails from a sprite image when hovering over the progress bar.
+Plugin to display thumbnails when hovering over the progress bar.
 
 ## Compatibility
 
@@ -29,9 +29,9 @@ This plugin version is compatible with Video.js v7.x and v6.x. Compatible [relea
 
 ## Features
 
+- works with single or multiple sprites containing thumbnails and individual thumbnail images
 - easy to [configure](#configuration)
 - uses [existing mouse time tooltip](#constraints)
-- focuses on use case of thumbnails combined in a sprite image only
 
 ## Installation
 
@@ -53,7 +53,7 @@ This is the simplest case. Get the script in whatever way you prefer and include
 <script>
   var player = videojs('my-video');
 
-  // set up 160x90 thumbnails in sprite.jpg, 1 per second
+  // set up 160x90 thumbnails in single sprite.jpg, 1 per second
   player.spriteThumbnails({
     url: 'https://example.com/sprite.jpg',
     width: 160,
@@ -77,10 +77,13 @@ require('videojs-sprite-thumbnails');
 
 var player = videojs('my-other-video');
 
+// More than 0 rows in combination with inserting {index) in the url
+// signals a sprite sequence.
 player.spriteThumbnails({
   interval: 3,
-  url: 'https://example.com/another-sprite.jpg',
-  columns: 10,
+  url: 'https://example.com/sprite_sequence-{index}.jpg',
+  columns: 5,
+  rows: 5,
   width: 120,
   height: 90
 });
@@ -117,11 +120,12 @@ Or load the latest Video.js v7.x/v6.x compatible release of the plugin via [scri
 
 option | type | mandatory | default | description
 ------ | ---- | --------- | ------- | -----------
-`url`  | String | &#10004; |   | Location of sprite image.
+`url`  | String | &#10004; |   | Location of image(s). Must be set by user. For multiple images the filename must contain the template `{index}` which is replaced by the zero based index number of the image in the sequence.
 `width` | Integer | &#10004; |  | Width of a thumbnail in pixels.
 `height` | Integer | &#10004; |   | Height of a thumbnail in pixels.
-`columns` | Integer | &#10004; |   | Number of columns in sprite image.
-`interval` | Number |  | `1` | Interval between thumbnail frames in seconds.
+`columns` | Integer | &#10004; |   | Number of thumbnail columns per image. Set both `columns` and `rows` to `1` for individual thumbnails.
+`rows` | Integer |  | `0` | Number of thumbnail rows per image. If set to greater than `0`, the plugin will expect a sequence of images. Set both `rows` and `columns` to `1` for individual thumbnails.
+`interval` | Number |  | `1` | Interval between thumbnails in seconds.
 `responsive` | Integer |  | `600` | Width of player in pixels below which thumbnails are responsive. Set to `0` to disable.
 `downlink` | Number |  | `1.5` | Minimum of required [NetworkInformation downlink][downlink] where supported. Set to `0` to disable.
 
@@ -131,7 +135,7 @@ The plugin is initialized at player setup. This is sufficient when the player wi
 
 The plugin also monitors all video sources on [loadstart](https://docs.videojs.com/player#event:loadstart) for a `spriteThumbnails` property which configures the plugin for this specific video. A typical use case are [playlists](#playlist-example).
 
-The sprite image is then loaded on demand, if and when the user moves the pointer on the seekbar.
+The image(s) are then loaded on demand, when the cursor hovers or moves over the progress bar.
 
 ### Playlist example
 
@@ -143,7 +147,7 @@ var playlist = [
 
     // only needed once, even if alternaive source is picked
     spriteThumbnails: {
-      url: 'https://example.com/thumbnails1.jpg'
+      url: 'https://example.com/thumbnails1-{index}.jpg'
     }
   }, {
     type: 'video/mp4',
@@ -152,7 +156,7 @@ var playlist = [
     type: 'application/x-mpegurl',
     src: 'https://example.com/video2.m3u8',
     spriteThumbnails: {
-      url: 'https://example.com/thumbnails2.jpg'
+      url: 'https://example.com/thumbnails2-{index}.jpg'
     }
   }]
 ];
@@ -168,7 +172,8 @@ var player = videojs('myplayer', {
     spriteThumbnails: {
       width: 160,
       height: 90,
-      columns: 5
+      columns: 5,
+      rows: 5
     }
   }
 });
@@ -193,10 +198,11 @@ The call can also be chained directly to the [manual plugin setup](https://docs.
 ```js
 var player = videojs('example-player');
 player.spriteThumbnails({
-  url: 'https://example.com/thumbnails.jpg',
+  url: 'https://example.com/thumbnails-{index}.jpg',
   width: 240,
   height: 100
-  columns: 7
+  columns: 7,
+  rows: 6
 }).log.level('debug');
 ```
 
diff --git a/package.json b/package.json
index 30d0bfc..dbea51f 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "videojs-sprite-thumbnails",
   "version": "1.1.2-dev",
-  "description": "Plugin to display thumbnails from a sprite image when hovering over the progress bar.",
+  "description": "Plugin to display thumbnails when hovering over the progress bar.",
   "repository": {
     "type": "git",
     "url": "git@github.com:phloxic/videojs-sprite-thumbnails.git"
diff --git a/src/plugin.js b/src/plugin.js
index fa4cc0a..9677fbd 100644
--- a/src/plugin.js
+++ b/src/plugin.js
@@ -8,13 +8,18 @@ const Plugin = videojs.getPlugin('plugin');
  * Default plugin options
  *
  * @param {String} url
- *        Location of sprite image(s). Must be set by user. Default: ''.
+ *        Location of image(s). Must be set by user. For multiple images the
+ *        filename must contain the template {index} which is replaced by the
+ *        zero based index number of the image in the sequence. Default: ''.
  * @param {Integer} width
  *        Width of a thumbnail in pixels. Must be set by user. Default: 0.
  * @param {Integer} height
  *        Height of a thumbnail in pixels. Must be set by user. Default: 0.
  * @param {Integer} columns
- *        Number of columns per sprite. Must be set by user.
+ *        Number of thumbnail columns per image. Must be set by user.
+ * @param {Integer} rows
+ *        Number of thumbnail rows per image. If set to greater than 0, the
+ *        plugin will expect a sequence of images. Default: 0.
  * @param {Number} interval
  *        Interval between thumbnail frames in seconds. Default: 1.
  * @param {Integer} responsive
@@ -28,6 +33,7 @@ const defaults = {
   width: 0,
   height: 0,
   columns: 0,
+  rows: 0,
   interval: 1,
   responsive: 600,
   downlink: 1.5
diff --git a/src/sprite-thumbnails.js b/src/sprite-thumbnails.js
index 4617e25..63e82f1 100644
--- a/src/sprite-thumbnails.js
+++ b/src/sprite-thumbnails.js
@@ -46,8 +46,21 @@ const spriteThumbs = (player, plugin, options) => {
     const columns = options.columns;
     const responsive = options.responsive;
 
-    const rows = Math.ceil(duration / interval * columns);
-    const position = dom.getPointerPosition(seekBarEl, evt).x * duration / interval;
+    const rowDuration = interval * columns;
+    let rows = options.rows || Math.ceil(duration / rowDuration);
+    // spriteDuration is needed to calculate idx and rows of last sprite
+    const spriteDuration = rowDuration * rows;
+
+    let position = dom.getPointerPosition(seekBarEl, evt).x * duration;
+    // for single sprites idx is always 0
+    const idx = Math.floor(position / spriteDuration);
+
+    // if (idx == 0) position /= interval
+    position = (position - spriteDuration * idx) / interval;
+    // Last (or only) sprite may have less rows, calculate required rows for it
+    if (idx === Math.floor(duration / spriteDuration)) {
+      rows -= Math.floor((spriteDuration * (idx + 1) - duration) / rowDuration);
+    }
 
     const scaleFactor = responsive && playerWidth < responsive ?
       playerWidth / responsive : 1;
@@ -61,7 +74,7 @@ const spriteThumbs = (player, plugin, options) => {
     const topOffset = -scaledHeight - Math.max(0, seekBarTop - controlsTop);
 
     const tooltipStyle = {
-      backgroundImage: `url("${options.url}")`,
+      backgroundImage: `url("${options.url.replace('{index}', idx)}")`,
       backgroundRepeat: 'no-repeat',
       backgroundPosition: `${cleft}px ${ctop}px`,
       backgroundSize: `${scaledWidth * columns}px ${scaledHeight * rows}px`,
@@ -82,9 +95,10 @@ const spriteThumbs = (player, plugin, options) => {
 
   const intCheck = (opt) => {
     const val = options[opt];
+    const min = opt !== 'rows' ? 1 : 0;
 
-    if (parseInt(val, 10) !== val || val < 1) {
-      log(`${opt} must be an integer greater than 0`);
+    if (parseInt(val, 10) !== val || val < min) {
+      log(`${opt} must be an integer greater than ${min - 1}`);
       return false;
     }
     return true;
@@ -110,7 +124,8 @@ const spriteThumbs = (player, plugin, options) => {
 
     plugin.setState({
       ready: !!(mouseTimeTooltip && options.url &&
-        intCheck('width') && intCheck('height') && intCheck('columns') && dl),
+        intCheck('width') && intCheck('height') && intCheck('columns') &&
+        intCheck('rows') && dl),
       diagnostics: true
     });
   };