Add tweet detail "/like" and "/unlike" URLs

- refactor TweetDetail to determine a bit more systematically whether scraping is required

internal/webserver/handler_tweet_detail.go

@@ -51,44 +51,71 @@ func (app *Application) TweetDetail(w http.ResponseWriter, r *http.Request) {
 	data := NewTweetDetailData()
 	data.MainTweetID = tweet_id
 
-	// Return whether the scrape succeeded (if false, we should 404)
-	try_scrape_tweet := func() bool {
-		if app.IsScrapingDisabled {
-			return false
-		}
-		trove, err := scraper.GetTweetFullAPIV2(tweet_id, 50) // TODO: parameterizable
-		if err != nil {
-			app.ErrorLog.Print(err)
-			return false
-		}
-		app.Profile.SaveTweetTrove(trove)
-		return true
-	}
+	is_needing_scrape := (len(parts) > 2 && parts[2] == "scrape")
+	is_available := false
 
+	// Check if tweet is already in DB
 	tweet, err := app.Profile.GetTweetById(tweet_id)
 	if err != nil {
 		if errors.Is(err, persistence.ErrNotInDB) {
-			if !try_scrape_tweet() {
-				app.error_404(w)
-				return
-			}
+			is_needing_scrape = true
+			is_available = false
 		} else {
 			panic(err)
 		}
-	} else if !tweet.IsConversationScraped || (len(parts) > 2 && parts[2] == "scrape") {
-		try_scrape_tweet() // If it fails, we can still render it (not 404)
+	} else {
+		is_available = true
+		if !tweet.IsConversationScraped {
+			is_needing_scrape = true
+		}
+	}
+	if is_available && len(parts) > 2 && (parts[2] == "like" || parts[2] == "unlike") {
+		is_needing_scrape = false
+	}
+
+	if is_needing_scrape && !app.IsScrapingDisabled {
+		trove, err := scraper.GetTweetFullAPIV2(tweet_id, 50) // TODO: parameterizable
+		if err == nil {
+			app.Profile.SaveTweetTrove(trove)
+			is_available = true
+		} else {
+			app.ErrorLog.Print(err)
+			// TODO: show error in UI
+		}
+	}
+
+	if !is_available {
+		app.error_404(w)
+		return
+	}
+
+	if len(parts) > 2 && parts[2] == "like" {
+		like, err := scraper.LikeTweet(tweet.ID)
+		// if err != nil && !errors.Is(err, scraper.AlreadyLikedThisTweet) {}
+		panic_if(err)
+		fmt.Printf("Like: %#v\n", like)
+		err = app.Profile.SaveLike(like)
+		panic_if(err)
+		tweet.IsLikedByCurrentUser = true
+
+		app.buffered_render_basic_htmx(w, "likes-count", tweet)
+		return
+	} else if len(parts) > 2 && parts[2] == "unlike" {
+		err = scraper.UnlikeTweet(tweet_id)
+		panic_if(err)
+		err = app.Profile.DeleteLike(scraper.Like{UserID: app.ActiveUser.ID, TweetID: tweet.ID})
+		panic_if(err)
+		tweet.IsLikedByCurrentUser = false
+
+		app.buffered_render_basic_htmx(w, "likes-count", tweet)
+		return
 	}
 
 	trove, err := app.Profile.GetTweetDetail(data.MainTweetID, app.ActiveUser.ID)
-	if err != nil {
-		if errors.Is(err, persistence.ErrNotInDB) {
-			app.error_404(w)
-			return
-		} else {
-			panic(err)
-		}
-	}
+	panic_if(err) // ErrNotInDB should be impossible, since we already fetched the single tweet successfully
+
 	data.TweetDetailView = trove
+	// fmt.Println(to_json(data))
 
 	app.buffered_render_tweet_page(w, "tpl/tweet_detail.tpl", data)
 }

internal/webserver/static/styles.css

@@ -574,6 +574,9 @@ ul.dropdown-items {
 .tweet video {
     max-height: 25em;
 }
+.like-icon {
+    cursor: pointer;
+}
 .like-icon.liked, .like-icon:hover {
     filter: invert(20%) sepia(97%) saturate(4383%) hue-rotate(321deg) brightness(101%) contrast(95%);
 }

internal/webserver/tpl/includes/likes_count.tpl

@@ -0,0 +1,10 @@
+{{define "likes-count"}}
+  <div class="interaction-stat" hx-trigger="click consume">
+    {{if .IsLikedByCurrentUser}}
+      <img class="svg-icon like-icon liked" src="/static/icons/like_filled.svg" hx-get="/tweet/{{.ID}}/unlike" hx-target="closest .interaction-stat" hx-push-url="false" hx-swap="outerHTML focus-scroll:false" />
+    {{else}}
+      <img class="svg-icon like-icon" src="/static/icons/like.svg" hx-get="/tweet/{{.ID}}/like" hx-target="closest .interaction-stat" hx-push-url="false" hx-swap="outerHTML focus-scroll:false" />
+    {{end}}
+    <span>{{.NumLikes}}</span>
+  </div>
+{{end}}

internal/webserver/tpl/tweet_page_includes/single_tweet.tpl

@@ -117,14 +117,7 @@
           <img class="svg-icon" src="/static/icons/retweet.svg" />
           <span>{{$main_tweet.NumRetweets}}</span>
         </div>
-        <div class="interaction-stat">
-          {{if $main_tweet.IsLikedByCurrentUser}}
-            <img class="svg-icon like-icon liked" src="/static/icons/like_filled.svg" />
-          {{else}}
-            <img class="svg-icon like-icon" src="/static/icons/like.svg" />
-          {{end}}
-          <span>{{$main_tweet.NumLikes}}</span>
-        </div>
+        {{template "likes-count" $main_tweet}}
         <div class="dummy"></div>
         <div class="dropdown" hx-trigger="click consume">
           <button class="dropdown-button" title="Options">