//
//  TransactionEnhancementTests.swift
//  ZcashLightClientKit-Unit-Tests
//
//  Created by Francisco Gindre on 4/15/20.
//

import XCTest
@testable import TestUtils
@testable import ZcashLightClientKit

// swiftlint:disable implicitly_unwrapped_optional force_try
class TransactionEnhancementTests: XCTestCase {
    let mockLatestHeight = BlockHeight(663250)
    let targetLatestHeight = BlockHeight(663251)
    let walletBirthday = BlockHeight(663150)
    let network = DarksideWalletDNetwork()
    let branchID = "2bb40e60"
    let chainName = "main"

    var initializer: Initializer!
    var processorConfig: CompactBlockProcessor.Configuration!
    var processor: CompactBlockProcessor!
    var darksideWalletService: DarksideWalletService!
    var downloader: CompactBlockDownloader!
    var downloadStartedExpect: XCTestExpectation!
    var updatedNotificationExpectation: XCTestExpectation!
    var stopNotificationExpectation: XCTestExpectation!
    var startedScanningNotificationExpectation: XCTestExpectation!
    var startedValidatingNotificationExpectation: XCTestExpectation!
    var idleNotificationExpectation: XCTestExpectation!
    var reorgNotificationExpectation: XCTestExpectation!
    var afterReorgIdleNotification: XCTestExpectation!
    var txFoundNotificationExpectation: XCTestExpectation!
    var waitExpectation: XCTestExpectation!

    override func setUpWithError() throws {
        try super.setUpWithError()
        logger = SampleLogger(logLevel: .debug)
        
        downloadStartedExpect = XCTestExpectation(description: "\(self.description) downloadStartedExpect")
        stopNotificationExpectation = XCTestExpectation(description: "\(self.description) stopNotificationExpectation")
        updatedNotificationExpectation = XCTestExpectation(description: "\(self.description) updatedNotificationExpectation")
        startedValidatingNotificationExpectation = XCTestExpectation(
            description: "\(self.description) startedValidatingNotificationExpectation"
        )
        startedScanningNotificationExpectation = XCTestExpectation(
            description: "\(self.description) startedScanningNotificationExpectation"
        )
        idleNotificationExpectation = XCTestExpectation(description: "\(self.description) idleNotificationExpectation")
        afterReorgIdleNotification = XCTestExpectation(description: "\(self.description) afterReorgIdleNotification")
        reorgNotificationExpectation = XCTestExpectation(description: "\(self.description) reorgNotificationExpectation")
        txFoundNotificationExpectation = XCTestExpectation(description: "\(self.description) txFoundNotificationExpectation")
        
        waitExpectation = XCTestExpectation(description: "\(self.description) waitExpectation")
        
        let birthday = Checkpoint.birthday(with: walletBirthday, network: network)
        
        let config = CompactBlockProcessor.Configuration.standard(for: self.network, walletBirthday: birthday.height)
        let rustBackend = ZcashRustBackend.self
        processorConfig = config
        
        try? FileManager.default.removeItem(at: processorConfig.cacheDb)
        try? FileManager.default.removeItem(at: processorConfig.dataDb)

        let dbInit = try rustBackend.initDataDb(dbData: processorConfig.dataDb, seed: nil, networkType: network.networkType)
        
        let ufvks = [
            try DerivationTool(networkType: network.networkType)
                .deriveUnifiedSpendingKey(seed: TestSeed().seed(), accountIndex: 0)
                .map{
                    try DerivationTool(networkType: network.networkType)
                        .deriveUnifiedFullViewingKey(from: $0)
                }

        ]
        do {
            try rustBackend.initAccountsTable(
                dbData: processorConfig.dataDb,
                ufvks: ufvks,
                networkType: network.networkType
            )
        } catch {
            XCTFail("Failed to init accounts table error: " + String(describing: rustBackend.getLastError()))
            return
        }
        
        guard case .success = dbInit else {
            XCTFail("Failed to initDataDb. Expected `.success` got: \(String(describing: dbInit))")
            return
        }

        _ = try rustBackend.initBlocksTable(
            dbData: processorConfig.dataDb,
            height: Int32(birthday.height),
            hash: birthday.hash,
            time: birthday.time,
            saplingTree: birthday.saplingTree,
            networkType: network.networkType
        )
        
        let service = DarksideWalletService()
        darksideWalletService = service
        let storage = CompactBlockStorage.init(connectionProvider: SimpleConnectionProvider(path: processorConfig.cacheDb.absoluteString))
        try! storage.createTable()
        
        downloader = CompactBlockDownloader(service: service, storage: storage)
        processor = CompactBlockProcessor(
            service: service,
            storage: storage,
            backend: rustBackend,
            config: processorConfig
        )
        
        NotificationCenter.default.addObserver(
            self,
            selector: #selector(processorFailed(_:)),
            name: Notification.Name.blockProcessorFailed,
            object: processor
        )
    }
    
    override func tearDownWithError() throws {
        try super.tearDownWithError()
        try? FileManager.default.removeItem(at: processorConfig.cacheDb)
        try? FileManager.default.removeItem(at: processorConfig.dataDb)
        downloadStartedExpect.unsubscribeFromNotifications()
        stopNotificationExpectation.unsubscribeFromNotifications()
        updatedNotificationExpectation.unsubscribeFromNotifications()
        startedScanningNotificationExpectation.unsubscribeFromNotifications()
        startedValidatingNotificationExpectation.unsubscribeFromNotifications()
        idleNotificationExpectation.unsubscribeFromNotifications()
        reorgNotificationExpectation.unsubscribeFromNotifications()
        afterReorgIdleNotification.unsubscribeFromNotifications()
        NotificationCenter.default.removeObserver(self)
    }
    
    private func startProcessing() async throws {
        XCTAssertNotNil(processor)
        
        // Subscribe to notifications
        downloadStartedExpect.subscribe(to: Notification.Name.blockProcessorStartedDownloading, object: processor)
        stopNotificationExpectation.subscribe(to: Notification.Name.blockProcessorStopped, object: processor)
        updatedNotificationExpectation.subscribe(to: Notification.Name.blockProcessorUpdated, object: processor)
        startedValidatingNotificationExpectation.subscribe(to: Notification.Name.blockProcessorStartedValidating, object: processor)
        startedScanningNotificationExpectation.subscribe(to: Notification.Name.blockProcessorStartedScanning, object: processor)

        txFoundNotificationExpectation.subscribe(to: .blockProcessorFoundTransactions, object: processor)
        idleNotificationExpectation.subscribe(to: .blockProcessorIdle, object: processor)
        await processor.start()
    }
    
    func testBasicEnhancement() async throws {
        let targetLatestHeight = BlockHeight(663200)
        
        do {
            try FakeChainBuilder.buildChain(darksideWallet: darksideWalletService, branchID: branchID, chainName: chainName)

            try darksideWalletService.applyStaged(nextLatestHeight: targetLatestHeight)
        } catch {
            XCTFail("Error: \(error)")
            return
        }

        sleep(3)

        /**
        connect to dLWD
        request latest height -> receive firstLatestHeight
        */
        do {
            dump("first latest height:  \(try darksideWalletService.latestBlockHeight())")
        } catch {
            XCTFail("Error: \(error)")
            return
        }

        /**
        download and sync blocks from walletBirthday to firstLatestHeight
        */
        do {
            try await startProcessing()
        } catch {
            XCTFail("Error: \(error)")
        }

        wait(
            for: [
                downloadStartedExpect,
                startedValidatingNotificationExpectation,
                startedScanningNotificationExpectation,
                txFoundNotificationExpectation,
                idleNotificationExpectation
            ],
            timeout: 30
        )
        idleNotificationExpectation.unsubscribeFromNotifications()
    }
    
    @objc func processorFailed(_ notification: Notification) {
        XCTAssertNotNil(notification.userInfo)
        if let error = notification.userInfo?["error"] {
            XCTFail("CompactBlockProcessor failed with Error: \(error)")
        } else {
            XCTFail("CompactBlockProcessor failed")
        }
    }
}