import * as vscode from "vscode"
import * as path from "path"
import { listFiles } from "../parse-source-code/index"
import { ClaudeDevProvider } from "../providers/ClaudeDevProvider"

const cwd = vscode.workspace.workspaceFolders?.map((folder) => folder.uri.fsPath).at(0)

// Note: this is not a drop-in replacement for listFiles at the start of tasks, since that will be done for Desktops when there is no workspace selected
class WorkspaceTracker {
	private providerRef: WeakRef<ClaudeDevProvider>
	private disposables: vscode.Disposable[] = []
	private filePaths: Set<string> = new Set()

	constructor(provider: ClaudeDevProvider) {
		this.providerRef = new WeakRef(provider)
		this.registerListeners()
	}

	async initializeFilePaths() {
		// should not auto get filepaths for desktop since it would immediately show permission popup before claude every creates a file
		if (!cwd) {
			return
		}
		const [files, _] = await listFiles(cwd, true, 500)
		files.forEach((file) => this.filePaths.add(this.normalizeFilePath(file)))
		this.workspaceDidUpdate()
	}

	private registerListeners() {
		// Listen for file creation
		// .bind(this) ensures the callback refers to class instance when using this, not necessary when using arrow function
		this.disposables.push(vscode.workspace.onDidCreateFiles(this.onFilesCreated.bind(this)))

		// Listen for file deletion
		this.disposables.push(vscode.workspace.onDidDeleteFiles(this.onFilesDeleted.bind(this)))

		// Listen for file renaming
		this.disposables.push(vscode.workspace.onDidRenameFiles(this.onFilesRenamed.bind(this)))

		/*
		 An event that is emitted when a workspace folder is added or removed.
		 **Note:** this event will not fire if the first workspace folder is added, removed or changed,
		 because in that case the currently executing extensions (including the one that listens to this
		 event) will be terminated and restarted so that the (deprecated) `rootPath` property is updated
		 to point to the first workspace folder.
		 */
		// In other words, we don't have to worry about the root workspace folder ([0]) changing since the extension will be restarted and our cwd will be updated to reflect the new workspace folder. (We don't care about non root workspace folders, since claude will only be working within the root folder cwd)
		// this.disposables.push(vscode.workspace.onDidChangeWorkspaceFolders(this.onWorkspaceFoldersChanged.bind(this)))
	}

	private async onFilesCreated(event: vscode.FileCreateEvent) {
		await Promise.all(
			event.files.map(async (file) => {
				await this.addFilePath(file.fsPath)
			})
		)
		this.workspaceDidUpdate()
	}

	private async onFilesDeleted(event: vscode.FileDeleteEvent) {
		let updated = false
		await Promise.all(
			event.files.map(async (file) => {
				if (await this.removeFilePath(file.fsPath)) {
					updated = true
				}
			})
		)
		if (updated) {
			this.workspaceDidUpdate()
		}
	}

	private async onFilesRenamed(event: vscode.FileRenameEvent) {
		await Promise.all(
			event.files.map(async (file) => {
				await this.removeFilePath(file.oldUri.fsPath)
				await this.addFilePath(file.newUri.fsPath)
			})
		)
		this.workspaceDidUpdate()
	}

	private workspaceDidUpdate() {
		if (!cwd) {
			return
		}
		this.providerRef.deref()?.postMessageToWebview({
			type: "workspaceUpdated",
			filePaths: Array.from(this.filePaths).map((file) => {
				const relativePath = path.relative(cwd, file)
				return file.endsWith("/") ? relativePath + "/" : relativePath
			}),
		})
	}

	private normalizeFilePath(filePath: string): string {
		const resolvedPath = path.resolve(filePath)
		return filePath.endsWith("/") ? resolvedPath + "/" : resolvedPath
	}

	private async addFilePath(filePath: string): Promise<string> {
		const normalizedPath = this.normalizeFilePath(filePath)
		try {
			const stat = await vscode.workspace.fs.stat(vscode.Uri.file(normalizedPath))
			const isDirectory = (stat.type & vscode.FileType.Directory) !== 0
			const pathWithSlash = isDirectory && !normalizedPath.endsWith("/") ? normalizedPath + "/" : normalizedPath
			this.filePaths.add(pathWithSlash)
			return pathWithSlash
		} catch {
			// If stat fails, assume it's a file (this can happen for newly created files)
			this.filePaths.add(normalizedPath)
			return normalizedPath
		}
	}

	private async removeFilePath(filePath: string): Promise<boolean> {
		const normalizedPath = this.normalizeFilePath(filePath)
		return this.filePaths.delete(normalizedPath) || this.filePaths.delete(normalizedPath + "/")
	}

	public dispose() {
		this.disposables.forEach((d) => d.dispose())
	}
}

export default WorkspaceTracker