import * as vscode from "vscode"
import * as path from "path"
import { CodeIndexConfigManager } from "./config-manager"
import { CodeIndexStateManager, IndexingState } from "./state-manager"
import { IFileWatcher, IVectorStore, BatchProcessingSummary } from "./interfaces"
import { DirectoryScanner } from "./processors"
import { CacheManager } from "./cache-manager"
import { TelemetryService } from "@roo-code/telemetry"
import { TelemetryEventName } from "@roo-code/types"
import { t } from "../../i18n"

/**
 * Manages the code indexing workflow, coordinating between different services and managers.
 */
export class CodeIndexOrchestrator {
	private _fileWatcherSubscriptions: vscode.Disposable[] = []
	private _isProcessing: boolean = false
	private _abortController: AbortController | null = null

	constructor(
		private readonly configManager: CodeIndexConfigManager,
		private readonly stateManager: CodeIndexStateManager,
		private readonly workspacePath: string,
		private readonly cacheManager: CacheManager,
		private readonly vectorStore: IVectorStore,
		private readonly scanner: DirectoryScanner,
		private readonly fileWatcher: IFileWatcher,
	) {}

	/**
	 * Starts the file watcher if not already running.
	 */
	private async _startWatcher(): Promise<void> {
		if (!this.configManager.isFeatureConfigured) {
			throw new Error("Cannot start watcher: Service not configured.")
		}

		this.stateManager.setSystemState("Indexing", "Initializing file watcher...")

		try {
			await this.fileWatcher.initialize()

			this._fileWatcherSubscriptions = [
				this.fileWatcher.onDidStartBatchProcessing((filePaths: string[]) => {}),
				this.fileWatcher.onBatchProgressUpdate(({ processedInBatch, totalInBatch, currentFile }) => {
					if (totalInBatch > 0 && this.stateManager.state !== "Indexing") {
						this.stateManager.setSystemState("Indexing", "Processing file changes...")
					}
					this.stateManager.reportFileQueueProgress(
						processedInBatch,
						totalInBatch,
						currentFile ? path.basename(currentFile) : undefined,
					)
					if (processedInBatch === totalInBatch) {
						// Covers (N/N) and (0/0)
						if (totalInBatch > 0) {
							// Batch with items completed
							this.stateManager.setSystemState("Indexed", "File changes processed. Index up-to-date.")
						} else {
							if (this.stateManager.state === "Indexing") {
								// Only transition if it was "Indexing"
								this.stateManager.setSystemState("Indexed", "Index up-to-date. File queue empty.")
							}
						}
					}
				}),
				this.fileWatcher.onDidFinishBatchProcessing((summary: BatchProcessingSummary) => {
					if (summary.batchError) {
						console.error(`[CodeIndexOrchestrator] Batch processing failed:`, summary.batchError)
					} else {
						const successCount = summary.processedFiles.filter(
							(f: { status: string }) => f.status === "success",
						).length
						const errorCount = summary.processedFiles.filter(
							(f: { status: string }) => f.status === "error" || f.status === "local_error",
						).length
					}
				}),
			]
		} catch (error) {
			console.error("[CodeIndexOrchestrator] Failed to start file watcher:", error)
			TelemetryService.instance.captureEvent(TelemetryEventName.CODE_INDEX_ERROR, {
				error: error instanceof Error ? error.message : String(error),
				stack: error instanceof Error ? error.stack : undefined,
				location: "_startWatcher",
			})
			throw error
		}
	}

	/**
	 * Updates the status of a file in the state manager.
	 */

	/**
	 * Initiates the indexing process (initial scan and starts watcher).
	 */
	public async startIndexing(): Promise<void> {
		// Check if workspace is available first
		if (!vscode.workspace.workspaceFolders || vscode.workspace.workspaceFolders.length === 0) {
			this.stateManager.setSystemState("Error", t("embeddings:orchestrator.indexingRequiresWorkspace"))
			console.warn("[CodeIndexOrchestrator] Start rejected: No workspace folder open.")
			return
		}

		if (!this.configManager.isFeatureConfigured) {
			this.stateManager.setSystemState("Standby", "Missing configuration. Save your settings to start indexing.")
			console.warn("[CodeIndexOrchestrator] Start rejected: Missing configuration.")
			return
		}

		if (
			this._isProcessing ||
			(this.stateManager.state !== "Standby" &&
				this.stateManager.state !== "Error" &&
				this.stateManager.state !== "Indexed")
		) {
			console.warn(
				`[CodeIndexOrchestrator] Start rejected: Already processing or in state ${this.stateManager.state}.`,
			)
			return
		}

		this._isProcessing = true
		this._abortController = new AbortController()
		const signal = this._abortController.signal
		this.stateManager.setSystemState("Indexing", "Initializing services...")

		// Track whether we successfully connected to Qdrant and started indexing
		// This helps us decide whether to preserve cache on error
		let indexingStarted = false

		try {
			const collectionCreated = await this.vectorStore.initialize()

			// Successfully connected to Qdrant
			indexingStarted = true

			if (collectionCreated) {
				await this.cacheManager.clearCacheFile()
			}

			// Check if the collection already has indexed data
			// If it does, we can skip the full scan and just start the watcher
			const hasExistingData = await this.vectorStore.hasIndexedData()

			if (hasExistingData && !collectionCreated) {
				// Collection exists with data - run incremental scan to catch any new/changed files
				// This handles files added while workspace was closed or Qdrant was inactive
				console.log(
					"[CodeIndexOrchestrator] Collection already has indexed data. Running incremental scan for new/changed files...",
				)
				this.stateManager.setSystemState("Indexing", "Checking for new or modified files...")

				// Mark as incomplete at the start of incremental scan
				await this.vectorStore.markIndexingIncomplete()

				let cumulativeBlocksIndexed = 0
				let cumulativeBlocksFoundSoFar = 0
				let batchErrors: Error[] = []

				const handleFileParsed = (fileBlockCount: number) => {
					cumulativeBlocksFoundSoFar += fileBlockCount
					this.stateManager.reportBlockIndexingProgress(cumulativeBlocksIndexed, cumulativeBlocksFoundSoFar)
				}

				const handleBlocksIndexed = (indexedCount: number) => {
					cumulativeBlocksIndexed += indexedCount
					this.stateManager.reportBlockIndexingProgress(cumulativeBlocksIndexed, cumulativeBlocksFoundSoFar)
				}

				// Run incremental scan - scanner will skip unchanged files using cache
				const result = await this.scanner.scanDirectory(
					this.workspacePath,
					(batchError: Error) => {
						console.error(
							`[CodeIndexOrchestrator] Error during incremental scan batch: ${batchError.message}`,
							batchError,
						)
						batchErrors.push(batchError)
					},
					handleBlocksIndexed,
					handleFileParsed,
					signal,
				)

				if (signal.aborted) {
					await this.cacheManager.flush()
					this.stopWatcher()
					this.stateManager.setSystemState("Standby", t("embeddings:orchestrator.indexingStopped"))
					return
				}

				if (!result) {
					throw new Error("Incremental scan failed, is scanner initialized?")
				}

				// If new files were found and indexed, log the results
				if (cumulativeBlocksFoundSoFar > 0) {
					console.log(
						`[CodeIndexOrchestrator] Incremental scan completed: ${cumulativeBlocksIndexed} blocks indexed from new/changed files`,
					)
				} else {
					console.log("[CodeIndexOrchestrator] No new or changed files found")
				}

				await this._startWatcher()

				// Mark indexing as complete after successful incremental scan
				await this.vectorStore.markIndexingComplete()

				this.stateManager.setSystemState("Indexed", t("embeddings:orchestrator.fileWatcherStarted"))
			} else {
				// No existing data or collection was just created - do a full scan
				this.stateManager.setSystemState("Indexing", "Services ready. Starting workspace scan...")

				// Mark as incomplete at the start of full scan
				await this.vectorStore.markIndexingIncomplete()

				let cumulativeBlocksIndexed = 0
				let cumulativeBlocksFoundSoFar = 0
				let batchErrors: Error[] = []

				const handleFileParsed = (fileBlockCount: number) => {
					cumulativeBlocksFoundSoFar += fileBlockCount
					this.stateManager.reportBlockIndexingProgress(cumulativeBlocksIndexed, cumulativeBlocksFoundSoFar)
				}

				const handleBlocksIndexed = (indexedCount: number) => {
					cumulativeBlocksIndexed += indexedCount
					this.stateManager.reportBlockIndexingProgress(cumulativeBlocksIndexed, cumulativeBlocksFoundSoFar)
				}

				const result = await this.scanner.scanDirectory(
					this.workspacePath,
					(batchError: Error) => {
						console.error(
							`[CodeIndexOrchestrator] Error during initial scan batch: ${batchError.message}`,
							batchError,
						)
						batchErrors.push(batchError)
					},
					handleBlocksIndexed,
					handleFileParsed,
					signal,
				)

				if (signal.aborted) {
					await this.cacheManager.flush()
					this.stopWatcher()
					this.stateManager.setSystemState("Standby", t("embeddings:orchestrator.indexingStopped"))
					return
				}

				if (!result) {
					throw new Error("Scan failed, is scanner initialized?")
				}

				const { stats } = result

				// Check if any blocks were actually indexed successfully
				// If no blocks were indexed but blocks were found, it means all batches failed
				if (cumulativeBlocksIndexed === 0 && cumulativeBlocksFoundSoFar > 0) {
					if (batchErrors.length > 0) {
						// Use the first batch error as it's likely representative of the main issue
						const firstError = batchErrors[0]
						throw new Error(`Indexing failed: ${firstError.message}`)
					} else {
						throw new Error(t("embeddings:orchestrator.indexingFailedNoBlocks"))
					}
				}

				// Check for partial failures - if a significant portion of blocks failed
				const failureRate = (cumulativeBlocksFoundSoFar - cumulativeBlocksIndexed) / cumulativeBlocksFoundSoFar
				if (batchErrors.length > 0 && failureRate > 0.1) {
					// More than 10% of blocks failed to index
					const firstError = batchErrors[0]
					throw new Error(
						`Indexing partially failed: Only ${cumulativeBlocksIndexed} of ${cumulativeBlocksFoundSoFar} blocks were indexed. ${firstError.message}`,
					)
				}

				// CRITICAL: If there were ANY batch errors and NO blocks were successfully indexed,
				// this is a complete failure regardless of the failure rate calculation
				if (batchErrors.length > 0 && cumulativeBlocksIndexed === 0) {
					const firstError = batchErrors[0]
					throw new Error(`Indexing failed completely: ${firstError.message}`)
				}

				// Final sanity check: If we found blocks but indexed none and somehow no errors were reported,
				// this is still a failure
				if (cumulativeBlocksFoundSoFar > 0 && cumulativeBlocksIndexed === 0) {
					throw new Error(t("embeddings:orchestrator.indexingFailedCritical"))
				}

				await this._startWatcher()

				// Mark indexing as complete after successful full scan
				await this.vectorStore.markIndexingComplete()

				this.stateManager.setSystemState("Indexed", t("embeddings:orchestrator.fileWatcherStarted"))
			}
		} catch (error: any) {
			// Handle abort gracefully — not an error, just a user-initiated stop
			if (error?.name === "AbortError" || signal.aborted) {
				console.log("[CodeIndexOrchestrator] Indexing aborted by user.")
				await this.cacheManager.flush()
				this.stopWatcher()
				this.stateManager.setSystemState("Standby", t("embeddings:orchestrator.indexingStopped"))
				return
			}

			console.error("[CodeIndexOrchestrator] Error during indexing:", error)
			TelemetryService.instance.captureEvent(TelemetryEventName.CODE_INDEX_ERROR, {
				error: error instanceof Error ? error.message : String(error),
				stack: error instanceof Error ? error.stack : undefined,
				location: "startIndexing",
			})
			if (indexingStarted) {
				try {
					await this.vectorStore.clearCollection()
				} catch (cleanupError) {
					console.error("[CodeIndexOrchestrator] Failed to clean up after error:", cleanupError)
					TelemetryService.instance.captureEvent(TelemetryEventName.CODE_INDEX_ERROR, {
						error: cleanupError instanceof Error ? cleanupError.message : String(cleanupError),
						stack: cleanupError instanceof Error ? cleanupError.stack : undefined,
						location: "startIndexing.cleanup",
					})
				}
			}

			// Only clear cache if indexing had started (Qdrant connection succeeded)
			// If we never connected to Qdrant, preserve cache for incremental scan when it comes back
			if (indexingStarted) {
				// Indexing started but failed mid-way - clear cache to avoid cache-Qdrant mismatch
				await this.cacheManager.clearCacheFile()
				console.log(
					"[CodeIndexOrchestrator] Indexing failed after starting. Clearing cache to avoid inconsistency.",
				)
			} else {
				// Never connected to Qdrant - preserve cache for future incremental scan
				console.log(
					"[CodeIndexOrchestrator] Failed to connect to Qdrant. Preserving cache for future incremental scan.",
				)
			}

			this.stateManager.setSystemState(
				"Error",
				t("embeddings:orchestrator.failedDuringInitialScan", {
					errorMessage: error.message || t("embeddings:orchestrator.unknownError"),
				}),
			)
			this.stopWatcher()
		} finally {
			this._isProcessing = false
			this._abortController = null
		}
	}

	/**
	 * Stops any in-progress indexing by aborting the scan and stopping the file watcher.
	 */
	public stopIndexing(): void {
		if (this._abortController) {
			this.stateManager.setSystemState("Stopping", t("embeddings:orchestrator.indexingStoppedPartial"))
			this._abortController.abort()
			this._abortController = null
		}
		this.stopWatcher()
	}

	/**
	 * Stops the file watcher and cleans up resources.
	 */
	public stopWatcher(): void {
		this.fileWatcher.dispose()
		this._fileWatcherSubscriptions.forEach((sub) => sub.dispose())
		this._fileWatcherSubscriptions = []

		if (this.stateManager.state !== "Error" && this.stateManager.state !== "Stopping") {
			this.stateManager.setSystemState("Standby", t("embeddings:orchestrator.fileWatcherStopped"))
		}
		this._isProcessing = false
	}

	/**
	 * Clears all index data by stopping the watcher, clearing the vector store,
	 * and resetting the cache file.
	 */
	public async clearIndexData(): Promise<void> {
		this._isProcessing = true

		try {
			await this.stopWatcher()

			try {
				if (this.configManager.isFeatureConfigured) {
					await this.vectorStore.deleteCollection()
				} else {
					console.warn("[CodeIndexOrchestrator] Service not configured, skipping vector collection clear.")
				}
			} catch (error: any) {
				console.error("[CodeIndexOrchestrator] Failed to clear vector collection:", error)
				TelemetryService.instance.captureEvent(TelemetryEventName.CODE_INDEX_ERROR, {
					error: error instanceof Error ? error.message : String(error),
					stack: error instanceof Error ? error.stack : undefined,
					location: "clearIndexData",
				})
				this.stateManager.setSystemState("Error", `Failed to clear vector collection: ${error.message}`)
			}

			await this.cacheManager.clearCacheFile()

			if (this.stateManager.state !== "Error") {
				this.stateManager.setSystemState("Standby", "Index data cleared successfully.")
			}
		} finally {
			this._isProcessing = false
		}
	}

	/**
	 * Gets the current state of the indexing system.
	 */
	public get state(): IndexingState {
		return this.stateManager.state
	}
}