import DbManager from "@shared-classes/DbManager"
import { Track } from "@db_models"
import axios from "axios"

async function main() {
	await global.injectEnvFromInfisical()

	const db = new DbManager()
	await db.initialize()

	const tracks = await Track.find()

	console.log(`Total tracks in database: ${tracks.length}`)

	// Group tracks by ETag
	const tracksByETag = new Map()

	for (const track of tracks) {
		if (
			!track.source ||
			typeof track.source !== "string" ||
			!track.source.startsWith("http")
		) {
			console.warn(
				`  Skipping track ID ${track._id} due to invalid or missing source URL: "${track.source}"`,
			)
			continue
		}

		const index = tracks.indexOf(track)

		try {
			console.log(
				`  [${index + 1}/${tracks.length}] Fetching ETag for source: ${track.source} (Track ID: ${track._id})`,
			)
			const response = await axios.head(track.source, {
				timeout: 10000, // 10 seconds timeout
				// Add headers to mimic a browser to avoid some 403s or other blocks
				headers: {
					"User-Agent":
						"Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/91.0.4472.124 Safari/537.36",
					Accept: "*/*", // More generic accept for HEAD
					"Accept-Encoding": "gzip, deflate, br",
					Connection: "keep-alive",
				},
			})
			// ETag header can be 'etag' or 'ETag' (case-insensitive)
			const etag = response.headers["etag"] || response.headers["ETag"]

			if (etag) {
				if (!tracksByETag.has(etag)) {
					tracksByETag.set(etag, [])
				}
				tracksByETag.get(etag).push(track)
				// console.log(`    ETag: ${etag} found for source: ${track.source}`)
			} else {
				console.warn(
					`  No ETag found for source: ${track.source} (Track ID: ${track._id})`,
				)
			}
		} catch (error) {
			let errorMessage = error.message
			if (error.response) {
				// The request was made and the server responded with a status code
				// that falls out of the range of 2xx
				errorMessage = `Server responded with status ${error.response.status} ${error.response.statusText}`
			} else if (error.request) {
				// The request was made but no response was received
				errorMessage =
					"No response received from server (e.g., timeout, network error)"
			}
			// else: Something happened in setting up the request that triggered an Error

			console.error(
				`  Error fetching ETag for ${track.source} (Track ID: ${track._id}): ${errorMessage}`,
			)
		}
	}

	console.log(
		`Finished fetching ETags. Found ${tracksByETag.size} unique ETags.`,
	)

	// Process groups to find and delete duplicates
	let deletedCount = 0

	for (const [etag, tracksForETag] of tracksByETag.entries()) {
		if (tracksForETag.length > 1) {
			console.log(
				`Found ${tracksForETag.length} tracks for ETag: "${etag}"`,
			)

			// Sort tracks by _id (lexicographically largest first - assuming larger _id is newer)
			// This ensures that we consistently pick the same track to keep if ETags are identical.
			tracksForETag.sort((a, b) =>
				b._id.toString().localeCompare(a._id.toString()),
			)

			const trackToKeep = tracksForETag[0]
			const tracksToDelete = tracksForETag.slice(1) // All tracks except the newest one

			if (tracksToDelete.length > 0) {
				const idsToDelete = tracksToDelete.map((track) => track._id)

				console.log(
					`  Keeping Track ID: ${trackToKeep._id} (Source: ${trackToKeep.source}) - selected due to largest _id (assumed newer).`,
				)
				tracksToDelete.forEach((t) => {
					console.log(
						`    Marking for deletion: Track ID: ${t._id} (Source: ${t.source})`,
					)
				})
				console.log(
					`  Attempting to delete ${idsToDelete.length} duplicate tracks for ETag: "${etag}"`,
				)

				try {
					const deleteResult = await Track.deleteMany({
						_id: { $in: idsToDelete },
					})

					if (deleteResult.deletedCount > 0) {
						console.log(
							`  Successfully deleted ${deleteResult.deletedCount} tracks for ETag: "${etag}"`,
						)
						deletedCount += deleteResult.deletedCount
					} else {
						console.warn(
							`  Deletion command executed for ETag "${etag}", but no tracks were deleted. IDs: ${idsToDelete.join(", ")}`,
						)
					}
				} catch (dbError) {
					console.error(
						`  Database error deleting tracks for ETag "${etag}": ${dbError.message}`,
					)
				}
			}
		}
	}
	console.log(`Finished processing. Total tracks deleted: ${deletedCount}.`)
}

main()