//
//  DynamicIslandViewModel.swift
//  DynamicIsland
//
//  Created by Harsh Vardhan  Goswami  on 04/08/24.
//

import Combine
import Defaults
import SwiftUI
import TheBoringWorkerNotifier

class DynamicIslandViewModel: NSObject, ObservableObject {
    @ObservedObject var coordinator = DynamicIslandViewCoordinator.shared
    @ObservedObject var detector = FullscreenMediaDetector.shared

    let animationLibrary: DynamicIslandAnimations = .init()
    let animation: Animation?

    @Published var contentType: ContentType = .normal
    @Published private(set) var notchState: NotchState = .closed

    @Published var dragDetectorTargeting: Bool = false
    @Published var dropZoneTargeting: Bool = false
    @Published var dropEvent: Bool = false
    @Published var anyDropZoneTargeting: Bool = false
    var cancellables: Set<AnyCancellable> = []
    
    @Published var hideOnClosed: Bool = true
    @Published var isHoveringCalendar: Bool = false
    @Published var isBatteryPopoverActive: Bool = false
    @Published var isClipboardPopoverActive: Bool = false
    
    let webcamManager = WebcamManager.shared
    @Published var isCameraExpanded: Bool = false
    @Published var isRequestingAuthorization: Bool = false

    @Published var screen: String?

    @Published var notchSize: CGSize = getClosedNotchSize()
    @Published var closedNotchSize: CGSize = getClosedNotchSize()
    
    deinit {
        destroy()
    }

    func destroy() {
        cancellables.forEach { $0.cancel() }
        cancellables.removeAll()
    }

    init(screen: String? = nil) {
        animation = animationLibrary.animation

        super.init()
        
        self.screen = screen
        notchSize = getClosedNotchSize(screen: screen)
        closedNotchSize = notchSize

        Publishers.CombineLatest($dropZoneTargeting, $dragDetectorTargeting)
            .map { value1, value2 in
                value1 || value2
            }
            .assign(to: \.anyDropZoneTargeting, on: self)
            .store(in: &cancellables)
        
        setupDetectorObserver()
    }
    
    private func setupDetectorObserver() {
        // 1) Publisher for the user’s fullscreen detection setting
        let enabledPublisher = Defaults
            .publisher(.enableFullscreenMediaDetection)
            .map(\.newValue)

        // 2) For each non‑nil screen name, map to a Bool publisher for that screen's status
        let statusPublisher = $screen
            .compactMap { $0 }
            .removeDuplicates()
            .map { screenName in
                self.detector.$fullscreenStatus
                    .map { $0[screenName] ?? false }
                    .removeDuplicates()
            }
            .switchToLatest()

        // 3) Combine enabled & status, animate only on changes
        Publishers.CombineLatest(statusPublisher, enabledPublisher)
            .map { status, enabled in enabled && status }
            .removeDuplicates()
            .receive(on: RunLoop.main)
            .sink { [weak self] shouldHide in
                withAnimation(.smooth) {
                    self?.hideOnClosed = shouldHide
                }
            }
            .store(in: &cancellables)
    }
    
    // Computed property for effective notch height
    var effectiveClosedNotchHeight: CGFloat {
        let currentScreen = NSScreen.screens.first { $0.localizedName == screen }
        let noNotchAndFullscreen = hideOnClosed && (currentScreen?.safeAreaInsets.top ?? 0 <= 0 || currentScreen == nil)
        return noNotchAndFullscreen ? 0 : closedNotchSize.height
    }

    func isMouseHovering(position: NSPoint = NSEvent.mouseLocation) -> Bool {
        let screenFrame = getScreenFrame(screen)
        if let frame = screenFrame {
            
            let baseY = frame.maxY - notchSize.height
            let baseX = frame.midX - notchSize.width / 2
            
            return position.y >= baseY && position.x >= baseX && position.x <= baseX + notchSize.width
        }
        
        return false
    }

    func open() {
        withAnimation(.bouncy) {
            self.notchSize = calculateDynamicNotchSize()
            self.notchState = .open
        }
        
        // Force music information update when notch is opened
        MusicManager.shared.forceUpdate()
    }
    
    private func calculateDynamicNotchSize() -> CGSize {
        // Only apply dynamic sizing when on stats tab and stats are enabled
        guard DynamicIslandViewCoordinator.shared.currentView == .stats && Defaults[.enableStatsFeature] else {
            return openNotchSize
        }
        
        let enabledGraphsCount = [
            Defaults[.showCpuGraph],
            Defaults[.showMemoryGraph], 
            Defaults[.showGpuGraph],
            Defaults[.showNetworkGraph],
            Defaults[.showDiskGraph]
        ].filter { $0 }.count
        
        // If 4+ graphs are enabled, increase width
        if enabledGraphsCount >= 4 {
            let extraWidth: CGFloat = CGFloat(enabledGraphsCount - 3) * 120
            return CGSize(width: openNotchSize.width + extraWidth, height: openNotchSize.height)
        }
        
        return openNotchSize
    }

    func close() {
        withAnimation(.smooth) { [weak self] in
            guard let self = self else { return }
            self.notchSize = getClosedNotchSize(screen: self.screen)
            self.closedNotchSize = self.notchSize
            self.notchState = .closed
        }

        // Set the current view to shelf if it contains files and the user enables openShelfByDefault
        // Otherwise, if the user has not enabled openLastShelfByDefault, set the view to home
        if !TrayDrop.shared.isEmpty && Defaults[.openShelfByDefault] {
            coordinator.currentView = .shelf
        } else if !coordinator.openLastTabByDefault {
            coordinator.currentView = .home
        }
    }

    func closeHello() {
        DispatchQueue.main.asyncAfter(deadline: .now() + 3.5) { [weak self] in
            self?.coordinator.firstLaunch = false
            withAnimation(self?.animationLibrary.animation) {
                self?.close()
            }
        }
    }
    
    func toggleCameraPreview() {
        if isRequestingAuthorization {
            return
        }

        switch webcamManager.authorizationStatus {
        case .authorized:
            if webcamManager.isSessionRunning {
                webcamManager.stopSession()
                isCameraExpanded = false
            } else if webcamManager.cameraAvailable {
                webcamManager.startSession()
                isCameraExpanded = true
            }

        case .denied, .restricted:
            DispatchQueue.main.async {
                NSApp.setActivationPolicy(.regular)
                NSApp.activate(ignoringOtherApps: true)

                let alert = NSAlert()
                alert.messageText = "Camera Access Required"
                alert.informativeText = "Please allow camera access in System Settings."
                alert.addButton(withTitle: "OK")
                alert.runModal()

                NSApp.setActivationPolicy(.accessory)
                NSApp.deactivate()
            }

        case .notDetermined:
            isRequestingAuthorization = true
            webcamManager.checkAndRequestVideoAuthorization()
            DispatchQueue.main.asyncAfter(deadline: .now() + 2) {
                self.isRequestingAuthorization = false
            }

        default:
            break
        }
    }
}