Rework subscribing to deleted channels

utils/youtube.js

@@ -2,14 +2,58 @@ const {request} = require("./request")
 const db = require("./db")
 
 async function fetchChannel(ucid, instance) {
+	function updateGoodData(channel) {
+		const bestIcon = channel.authorThumbnails.slice(-1)[0]
+		const iconURL = bestIcon ? bestIcon.url : null
+		db.prepare("REPLACE INTO Channels (ucid, name, icon_url, missing, missing_reason) VALUES (?, ?, ?, 0, NULL)").run(channel.authorId, channel.author, iconURL)
+	}
+
+	function updateBadData(channel) {
+		if (channel.identifier === "NOT_FOUND" || channel.identifier === "ACCOUNT_TERMINATED") {
+			db.prepare("UPDATE Channels SET missing = 1, missing_reason = ? WHERE ucid = ?").run(channel.error, channel.authorId)
+			return {
+				missing: true,
+				message: channel.error
+			}
+		} else {
+			return {
+				missing: false,
+				message: channel.error
+			}
+		}
+	}
+
 	if (!instance) throw new Error("No instance parameter provided")
-	// fetch
+
+	const row = db.prepare("SELECT * FROM Channels WHERE ucid = ?").get(ucid)
+
+	// handle the case where the channel has a known error
+	if (row && row.missing_reason) {
+		return {
+			error: true,
+			ucid,
+			row,
+			missing: true,
+			message: row.missing_reason
+		}
+	}
+
+	/** @type {any} */
 	const channel = await request(`${instance}/api/v1/channels/${ucid}`).then(res => res.json())
-	// update database
-	const bestIcon = channel.authorThumbnails.slice(-1)[0]
-	const iconURL = bestIcon ? bestIcon.url : null
-	db.prepare("REPLACE INTO Channels (ucid, name, icon_url) VALUES (?, ?, ?)").run([channel.authorId, channel.author, iconURL])
-	// return
+
+	// handle the case where the channel has a newly discovered error
+	if (channel.error) {
+		const missingData = updateBadData(channel)
+		return {
+			error: true,
+			ucid,
+			row,
+			...missingData
+		}
+	}
+
+	// handle the case where the channel returns good data (this is the only remaining scenario)
+	updateGoodData(channel)
 	return channel
 }