4 files changed, 166 insertions, 68 deletions

diff --git a/client/src/app/+my-account/my-account-video-playlists/my-account-video-playlist-elements.component.html b/client/src/app/+my-account/my-account-video-playlists/my-account-video-playlist-elements.component.html
index e2d09a36d..67a8b1a91 100644
--- a/client/src/app/+my-account/my-account-video-playlists/my-account-video-playlist-elements.component.html
+++ b/client/src/app/+my-account/my-account-video-playlists/my-account-video-playlist-elements.component.html
@@ -1,7 +1,10 @@
 <div i18n class="no-results" *ngIf="pagination.totalItems === 0">No videos in this playlist.</div>
 
-<div class="videos" myInfiniteScroller (nearOfBottom)="onNearOfBottom()">
-  <div *ngFor="let video of videos" class="video">
+<div
+  class="videos" myInfiniteScroller [autoInit]="true" (nearOfBottom)="onNearOfBottom()"
+  cdkDropList (cdkDropListDropped)="drop($event)"
+>
+  <div class="video" *ngFor="let video of videos" cdkDrag (cdkDragMoved)="onDragMove($event)">
     <div class="position">{{ video.playlistElement.position }}</div>
 
     <my-video-thumbnail [video]="video" [nsfw]="isVideoBlur(video)"></my-video-thumbnail>
diff --git a/client/src/app/+my-account/my-account-video-playlists/my-account-video-playlist-elements.component.scss b/client/src/app/+my-account/my-account-video-playlists/my-account-video-playlist-elements.component.scss
index 3be10078e..4ac89d08f 100644
--- a/client/src/app/+my-account/my-account-video-playlists/my-account-video-playlist-elements.component.scss
+++ b/client/src/app/+my-account/my-account-video-playlists/my-account-video-playlist-elements.component.scss
@@ -2,95 +2,121 @@
 @import '_mixins';
 @import '_miniature';
 
-.videos {
-  .video {
+.video, .cdk-drag-preview {
+  display: flex;
+  align-items: center;
+  background-color: var(--mainBackgroundColor);
+  cursor: pointer;
+  padding: 10px;
+  border-bottom: 1px solid $separator-border-color;
+
+  &:hover {
+    background-color: rgba(0, 0, 0, 0.05);
+
+    .more {
+      display: block;
+    }
+  }
+
+  .position {
+    font-weight: $font-semibold;
+    margin-right: 10px;
+    color: $grey-foreground-color;
+    min-width: 20px;
+  }
+
+  my-video-thumbnail {
+    display: flex; // Avoids an issue with line-height that adds space below the element
+    margin-right: 10px;
+
+    /deep/ .video-thumbnail {
+      @include miniature-thumbnail(130px, 72px);
+    }
+  }
+
+  .video-info {
     display: flex;
-    align-items: center;
-    padding: 10px;
-    border-bottom: 1px solid $separator-border-color;
+    flex-direction: column;
 
-    &:hover {
-      background-color: rgba(0, 0, 0, 0.05);
+    a {
+      @include disable-default-a-behaviour;
 
-      .more {
-        display: block;
-      }
+      color: var(--mainForegroundColor);
     }
 
-    .position {
+    .video-info-name {
+      font-size: 18px;
       font-weight: $font-semibold;
-      margin-right: 10px;
-      color: $grey-foreground-color;
     }
 
-    my-video-thumbnail {
-      display: flex; // Avoids an issue with line-height that adds space below the element
-      margin-right: 10px;
-
-      /deep/ .video-thumbnail {
-        @include miniature-thumbnail(130px, 72px);
-      }
+    .video-info-account, .video-info-timestamp {
+      color: $grey-foreground-color;
     }
+  }
 
-    .video-info {
-      display: flex;
-      flex-direction: column;
+  .more {
+    justify-self: flex-end;
+    margin-left: auto;
+    cursor: pointer;
+    display: none;
 
-      a {
-        @include disable-default-a-behaviour;
+    &.show {
+      display: block;
+    }
 
-        color: var(--mainForegroundColor);
-      }
+    .icon-more {
+      @include apply-svg-color($grey-foreground-color);
 
-      .video-info-name {
-        font-size: 18px;
-        font-weight: $font-semibold;
+      &::after {
+        border: none;
       }
+    }
 
-      .video-info-account, .video-info-timestamp {
-        color: $grey-foreground-color;
-      }
+    .dropdown-item {
+      @include dropdown-with-icon-item;
     }
 
-    .more {
-      justify-self: flex-end;
-      margin-left: auto;
-      cursor: pointer;
-      display: none;
+    .timestamp-options {
+      padding-top: 0;
+      padding-left: 35px;
+      margin-bottom: 15px;
 
-      &.show {
-        display: block;
+      > div {
+        display: flex;
+        align-items: center;
       }
 
-      .icon-more {
-        @include apply-svg-color($grey-foreground-color);
+      input {
+        @include peertube-button;
+        @include orange-button;
 
-        &::after {
-          border: none;
-        }
+        margin-top: 10px;
       }
+    }
+  }
+}
 
-      .dropdown-item {
-        @include dropdown-with-icon-item;
-      }
+// Thanks Angular CDK <3 https://material.angular.io/cdk/drag-drop/examples
+.cdk-drag-preview {
+  box-sizing: border-box;
+  border-radius: 4px;
+  box-shadow: 0 5px 5px -3px rgba(0, 0, 0, 0.2),
+  0 8px 10px 1px rgba(0, 0, 0, 0.14),
+  0 3px 14px 2px rgba(0, 0, 0, 0.12);
+}
 
-      .timestamp-options {
-        padding-top: 0;
-        padding-left: 35px;
-        margin-bottom: 15px;
+.cdk-drag-placeholder {
+  opacity: 0;
+}
 
-        > div {
-          display: flex;
-          align-items: center;
-        }
+.cdk-drag-animating {
+  transition: transform 250ms cubic-bezier(0, 0, 0.2, 1);
+}
 
-        input {
-          @include peertube-button;
-          @include orange-button;
+.video:last-child {
+  border: none;
+}
 
-          margin-top: 10px;
-        }
-      }
-    }
-  }
+.videos.cdk-drop-list-dragging .video:not(.cdk-drag-placeholder) {
+  transition: transform 250ms cubic-bezier(0, 0, 0.2, 1);
 }
diff --git a/client/src/app/+my-account/my-account-video-playlists/my-account-video-playlist-elements.component.ts b/client/src/app/+my-account/my-account-video-playlists/my-account-video-playlist-elements.component.ts
index 76aff3d4f..4076a3721 100644
--- a/client/src/app/+my-account/my-account-video-playlists/my-account-video-playlist-elements.component.ts
+++ b/client/src/app/+my-account/my-account-video-playlists/my-account-video-playlist-elements.component.ts
@@ -4,7 +4,7 @@ import { AuthService } from '../../core/auth'
 import { ConfirmService } from '../../core/confirm'
 import { ComponentPagination } from '@app/shared/rest/component-pagination.model'
 import { Video } from '@app/shared/video/video.model'
-import { Subscription } from 'rxjs'
+import { Subject, Subscription } from 'rxjs'
 import { ActivatedRoute } from '@angular/router'
 import { VideoService } from '@app/shared/video/video.service'
 import { VideoPlaylistService } from '@app/shared/video-playlist/video-playlist.service'
@@ -13,6 +13,8 @@ import { I18n } from '@ngx-translate/i18n-polyfill'
 import { secondsToTime } from '../../../assets/player/utils'
 import { VideoPlaylistElementUpdate } from '@shared/models'
 import { NgbDropdown } from '@ng-bootstrap/ng-bootstrap'
+import { CdkDragDrop, CdkDragMove } from '@angular/cdk/drag-drop'
+import { throttleTime } from 'rxjs/operators'
 
 @Component({
   selector: 'my-account-video-playlist-elements',
@@ -42,6 +44,7 @@ export class MyAccountVideoPlaylistElementsComponent implements OnInit, OnDestro
 
   private videoPlaylistId: string | number
   private paramsSub: Subscription
+  private dragMoveSubject = new Subject<number>()
 
   constructor (
     private authService: AuthService,
@@ -61,12 +64,66 @@ export class MyAccountVideoPlaylistElementsComponent implements OnInit, OnDestro
 
       this.loadPlaylistInfo()
     })
+
+    this.dragMoveSubject.asObservable()
+      .pipe(throttleTime(200))
+      .subscribe(y => this.checkScroll(y))
   }
 
   ngOnDestroy () {
     if (this.paramsSub) this.paramsSub.unsubscribe()
   }
 
+  drop (event: CdkDragDrop<any>) {
+    const previousIndex = event.previousIndex
+    const newIndex = event.currentIndex
+
+    if (previousIndex === newIndex) return
+
+    const oldPosition = this.videos[previousIndex].playlistElement.position
+    const insertAfter = newIndex === 0 ? 0 : this.videos[newIndex].playlistElement.position
+
+    this.videoPlaylistService.reorderPlaylist(this.playlist.id, oldPosition, insertAfter)
+      .subscribe(
+        () => { /* nothing to do */ },
+
+        err => this.notifier.error(err.message)
+      )
+
+    const video = this.videos[previousIndex]
+
+    this.videos.splice(previousIndex, 1)
+    this.videos.splice(newIndex, 0, video)
+
+    this.reorderClientPositions()
+  }
+
+  onDragMove (event: CdkDragMove<any>) {
+    this.dragMoveSubject.next(event.pointerPosition.y)
+  }
+
+  checkScroll (pointerY: number) {
+    // FIXME: Uncomment when https://github.com/angular/material2/issues/14098 is fixed
+    // FIXME: Remove when https://github.com/angular/material2/issues/13588 is implemented
+    // if (pointerY < 150) {
+    //   window.scrollBy({
+    //     left: 0,
+    //     top: -20,
+    //     behavior: 'smooth'
+    //   })
+    //
+    //   return
+    // }
+    //
+    // if (window.innerHeight - pointerY <= 50) {
+    //   window.scrollBy({
+    //     left: 0,
+    //     top: 20,
+    //     behavior: 'smooth'
+    //   })
+    // }
+  }
+
   isVideoBlur (video: Video) {
     return video.isVideoNSFWForUser(this.authService.getUser(), this.serverService.getConfig())
   }
@@ -78,6 +135,7 @@ export class MyAccountVideoPlaylistElementsComponent implements OnInit, OnDestro
             this.notifier.success(this.i18n('Video removed from {{name}}', { name: this.playlist.displayName }))
 
             this.videos = this.videos.filter(v => v.id !== video.id)
+            this.reorderClientPositions()
           },
 
           err => this.notifier.error(err.message)
@@ -173,4 +231,13 @@ export class MyAccountVideoPlaylistElementsComponent implements OnInit, OnDestro
         this.playlist = playlist
       })
   }
+
+  private reorderClientPositions () {
+    let i = 1
+
+    for (const video of this.videos) {
+      video.playlistElement.position = i
+      i++
+    }
+  }
 }
diff --git a/client/src/app/+my-account/my-account.module.ts b/client/src/app/+my-account/my-account.module.ts
index ba8300111..4a18a9968 100644
--- a/client/src/app/+my-account/my-account.module.ts
+++ b/client/src/app/+my-account/my-account.module.ts
@@ -35,6 +35,7 @@ import { MyAccountVideoPlaylistsComponent } from '@app/+my-account/my-account-vi
 import {
   MyAccountVideoPlaylistElementsComponent
 } from '@app/+my-account/my-account-video-playlists/my-account-video-playlist-elements.component'
+import { DragDropModule } from '@angular/cdk/drag-drop'
 
 @NgModule({
   imports: [
@@ -43,7 +44,8 @@ import {
     AutoCompleteModule,
     SharedModule,
     TableModule,
-    InputSwitchModule
+    InputSwitchModule,
+    DragDropModule
   ],
 
   declarations: [