import SwiftUI
import AppKit

struct LicenseEntryView: View {
    @ObservedObject private var licenseManager = LicenseManager.shared
    @Environment(\.presentationMode) var presentationMode
    
    @State private var licenseKey = ""
    @State private var userName = ""
    @State private var isVerifying = false
    @State private var errorMessage = ""
    @State private var showError = false
    
    // Add closure for window dismissal
    var onDismiss: (() -> Void)?
    
    init(onDismiss: (() -> Void)? = nil) {
        self.onDismiss = onDismiss
    }
    
    var body: some View {
        VStack(spacing: 0) {
            ScrollView {
                VStack(spacing: 24) {
                    // Add minimal top padding since traffic lights are hidden
                    Spacer()
                        .frame(height: 20)
                    
                    VStack(spacing: 24) {
                        // Header Section - similar to SettingsTabView
                        VStack(spacing: 16) {
                            // Replace key icon with ShotScreen icon at native 200x200 resolution
                            Group {
                                if let shotScreenIcon = NSImage(named: "ShotScreenIcon_200x200") {
                                    Image(nsImage: shotScreenIcon)
                                        .resizable()
                                        .aspectRatio(contentMode: .fit)
                                        .frame(width: 200, height: 200)
                                        .cornerRadius(20)
                                } else if let bundle = Bundle.main.url(forResource: "images/ShotScreenIcon_200x200", withExtension: "png"),
                                          let nsImage = NSImage(contentsOf: bundle) {
                                    Image(nsImage: nsImage)
                                        .resizable()
                                        .aspectRatio(contentMode: .fit)
                                        .frame(width: 200, height: 200)
                                        .cornerRadius(20)
                                } else {
                                    // Fallback to system icon if ShotScreenIcon_200x200 not found
                                    Image(systemName: "key.fill")
                                        .font(.system(size: 48))
                                        .foregroundColor(.blue)
                                }
                            }
                            
                            VStack(spacing: 8) {
                                Text(headerTitle)
                                    .font(.largeTitle)
                                    .fontWeight(.bold)
                                    .foregroundColor(.primary)
                                    .multilineTextAlignment(.center)
                                
                                Text(headerSubtitle)
                                    .font(.subheadline)
                                    .foregroundColor(.secondary)
                                    .multilineTextAlignment(.center)
                            }
                        }
                        .padding(.top, 10)
                        .padding(.bottom, 10)
                        
                        // Trial Status Section
                        switch licenseManager.licenseStatus {
                        case .trial(let daysLeft):
                            VStack(alignment: .leading, spacing: 16) {
                                VStack(alignment: .leading, spacing: 8) {
                                    Text("Trial Status")
                                        .font(.title2)
                                        .fontWeight(.semibold)
                                        .foregroundColor(.primary)
                                    Divider()
                                }
                                
                                HStack {
                                    Image(systemName: "clock.fill")
                                        .foregroundColor(.orange)
                                    Text("\(daysLeft) days remaining in your free trial")
                                        .foregroundColor(.secondary)
                                }
                                
                                Text("Already purchased? Enter your license key below to activate the full version.")
                                    .font(.caption)
                                    .foregroundColor(.secondary)
                            }
                            .padding(20)
                            .background(Color.primary.opacity(0.03))
                            .cornerRadius(12)
                            
                        case .expired:
                            VStack(alignment: .leading, spacing: 16) {
                                VStack(alignment: .leading, spacing: 8) {
                                    Text("Trial Expired")
                                        .font(.title2)
                                        .fontWeight(.semibold)
                                        .foregroundColor(.red)
                                    Divider()
                                }
                                
                                HStack {
                                    Image(systemName: "exclamationmark.triangle.fill")
                                        .foregroundColor(.red)
                                    Text("Your 7-day trial has expired")
                                        .foregroundColor(.secondary)
                                }
                                
                                Text("Purchase a license or enter your license key to continue using ShotScreen.")
                                    .font(.caption)
                                    .foregroundColor(.secondary)
                            }
                            .padding(20)
                            .background(Color.red.opacity(0.05))
                            .cornerRadius(12)
                            
                        default:
                            EmptyView()
                        }
                        
                        // License Entry Form Section
                        VStack(alignment: .leading, spacing: 16) {
                            VStack(alignment: .leading, spacing: 8) {
                                Text("License Information")
                                    .font(.title2)
                                    .fontWeight(.semibold)
                                    .foregroundColor(.primary)
                                Divider()
                            }
                            
                            VStack(spacing: 16) {
                                VStack(alignment: .leading, spacing: 8) {
                                    Text("Your Name")
                                        .font(.headline)
                                        .foregroundColor(.primary)
                                    TextField("Enter your full name", text: $userName)
                                        .textFieldStyle(RoundedBorderTextFieldStyle())
                                        .disabled(isVerifying)
                                }
                                
                                VStack(alignment: .leading, spacing: 8) {
                                    Text("License Key")
                                        .font(.headline)
                                        .foregroundColor(.primary)
                                    TextField("XXXX-XXXX-XXXX-XXXX", text: $licenseKey)
                                        .textFieldStyle(RoundedBorderTextFieldStyle())
                                        .font(.system(.body, design: .monospaced))
                                        .disabled(isVerifying)
                                }
                                
                                if showError {
                                    HStack {
                                        Image(systemName: "exclamationmark.triangle.fill")
                                            .foregroundColor(.red)
                                        Text(errorMessage)
                                            .foregroundColor(.red)
                                            .font(.caption)
                                    }
                                    .padding(.horizontal, 12)
                                    .padding(.vertical, 8)
                                    .background(Color.red.opacity(0.1))
                                    .cornerRadius(8)
                                }
                            }
                        }
                        .padding(20)
                        .background(Color.primary.opacity(0.03))
                        .cornerRadius(12)
                        
                        Spacer()
                    }
                    .padding()
                }
            }
            
            Divider()
            
            // Bottom Button Section - matching SettingsTabView style
            HStack {
                Button(action: activateLicense) {
                    HStack {
                        if isVerifying {
                            ProgressView()
                                .scaleEffect(0.7)
                        }
                        Text(isVerifying ? "Verifying..." : "Activate License")
                    }
                }
                .buttonStyle(.borderedProminent)
                .disabled(!canActivate || isVerifying)
                .keyboardShortcut(.defaultAction)   // Return key = Activate
                
                Spacer()
                
                Button("Buy License") {
                    openPurchaseURL()
                }
                .buttonStyle(.bordered)
                
                Button("Cancel") {
                    dismissWindow()
                }
                .buttonStyle(.bordered)
            }
            .padding()
        }
        .frame(minWidth: 600, idealWidth: 650, minHeight: 700, idealHeight: 750)
        .background(Color.clear)
    }
    
    private var canActivate: Bool {
        !licenseKey.trimmingCharacters(in: .whitespacesAndNewlines).isEmpty &&
        !userName.trimmingCharacters(in: .whitespacesAndNewlines).isEmpty
    }
    
    private var headerTitle: String {
        switch licenseManager.licenseStatus {
        case .trial(_):
            return "Activate ShotScreen"
        case .expired:
            return "Unlock ShotScreen"
        default:
            return "Activate ShotScreen"
        }
    }
    
    private var headerSubtitle: String {
        switch licenseManager.licenseStatus {
        case .trial(_):
            return "Already have a license? Enter your license key below."
        case .expired:
            return "Your free trial has ended. Enter your license key to continue using ShotScreen."
        default:
            return "Enter your license key to unlock the full version"
        }
    }
    
    private func activateLicense() {
        guard canActivate else { return }
        
        isVerifying = true
        showError = false
        errorMessage = ""
        
        Task {
            let success = await licenseManager.enterLicenseKey(
                licenseKey.trimmingCharacters(in: .whitespacesAndNewlines),
                userName: userName.trimmingCharacters(in: .whitespacesAndNewlines)
            )
            
            await MainActor.run {
                isVerifying = false
                
                if success {
                    dismissWindow()
                } else {
                    showError = true
                    errorMessage = "Invalid license key or verification failed. Please check your license key and internet connection."
                }
            }
        }
    }
    
    private func openPurchaseURL() {
        // ShotScreen Gumroad license product
        if let url = URL(string: "https://roodenrijs.gumroad.com/l/uxexr") {
            NSWorkspace.shared.open(url)
        }
    }
    
    private func dismissWindow() {
        onDismiss?()
        presentationMode.wrappedValue.dismiss()
    }
}

// MARK: - License Entry Window
class LicenseEntryWindow: NSWindow {
    private var visualEffectViewContainer: NSView?
    
    override init(contentRect: NSRect, styleMask style: NSWindow.StyleMask, backing backingStoreType: NSWindow.BackingStoreType, defer flag: Bool) {
        super.init(contentRect: contentRect, styleMask: style, backing: backingStoreType, defer: flag)
        setupWindow()
    }
    
    convenience init() {
        self.init(
            contentRect: NSRect(x: 0, y: 0, width: 650, height: 750),
            styleMask: [.titled, .closable, .resizable, .fullSizeContentView],
            backing: .buffered,
            defer: false
        )
    }
    
    private func setupWindow() {
        title = "ShotScreen License"
        isReleasedWhenClosed = false
        center()
        
        // Ensure the window appears in front and can be brought to front
        level = .normal
        collectionBehavior = [.canJoinAllSpaces, .fullScreenAuxiliary]
        
        // Apply same blur style as SettingsWindow
        isOpaque = false
        backgroundColor = .clear 
        titlebarAppearsTransparent = true
        titleVisibility = .hidden 
        isMovableByWindowBackground = true
        
        // Hide traffic lights (red, yellow, green buttons) to prevent content overlap
        standardWindowButton(.closeButton)?.isHidden = true
        standardWindowButton(.miniaturizeButton)?.isHidden = true
        standardWindowButton(.zoomButton)?.isHidden = true
        
        // Create content view with dismissal callback
        let licenseView = LicenseEntryView(onDismiss: { [weak self] in
            self?.close()
        })
        let hostingView = NSHostingView(rootView: licenseView)
        
        // Apply same visual effect as SettingsWindow
        let visualEffectView = NSVisualEffectView()
        visualEffectView.blendingMode = .behindWindow
        visualEffectView.material = .hudWindow          // Same strong system blur
        visualEffectView.state = .active
        visualEffectView.alphaValue = 1.0
        visualEffectView.autoresizingMask = [.width, .height]

        // Extra blur layer for enhanced effect
        let extraBlurView = NSVisualEffectView()
        extraBlurView.blendingMode = .behindWindow      
        extraBlurView.material = .hudWindow
        extraBlurView.state  = .active
        extraBlurView.alphaValue = 0.6                  // Half transparent for optical blur enhancement
        extraBlurView.autoresizingMask = [.width, .height]

        let newRootContentView = NSView(frame: contentRect(forFrameRect: frame))

        // Layer order: strongest blur at bottom, half blur above, SwiftUI content on top
        visualEffectView.frame = newRootContentView.bounds
        extraBlurView.frame   = newRootContentView.bounds

        newRootContentView.addSubview(visualEffectView)     // Layer 0
        newRootContentView.addSubview(extraBlurView)        // Layer 1 (enhancement)
        newRootContentView.addSubview(hostingView)          // Layer 2 (UI)

        contentView = newRootContentView
        visualEffectViewContainer = newRootContentView
        
        hostingView.wantsLayer = true
        hostingView.layer?.backgroundColor = NSColor.clear.cgColor
        
        hostingView.translatesAutoresizingMaskIntoConstraints = false
        NSLayoutConstraint.activate([
            hostingView.topAnchor.constraint(equalTo: newRootContentView.topAnchor),
            hostingView.bottomAnchor.constraint(equalTo: newRootContentView.bottomAnchor),
            hostingView.leadingAnchor.constraint(equalTo: newRootContentView.leadingAnchor),
            hostingView.trailingAnchor.constraint(equalTo: newRootContentView.trailingAnchor)
        ])
        
        // Force a layout pass after setting up the hierarchy
        contentView?.layoutSubtreeIfNeeded()
        
        // Window appearance
        delegate = self
        
        // Better window management - bring to front
        orderFrontRegardless()
        makeKeyAndOrderFront(nil)
    }
    
    deinit {
        print("🗑️ LicenseEntryWindow deinitialized safely")
    }
}

// MARK: - Window Delegate
extension LicenseEntryWindow: NSWindowDelegate {
    func windowShouldClose(_ sender: NSWindow) -> Bool {
        // Allow closing
        return true
    }
    
    func windowWillClose(_ notification: Notification) {
        // Clean up when window is about to close
        contentView = nil
        delegate = nil
        print("🪟 License window closing gracefully")
    }
}

// MARK: - Trial Expired View
struct TrialExpiredView: View {
    @ObservedObject private var licenseManager = LicenseManager.shared
    
    var body: some View {
        VStack(spacing: 24) {
            // Replace with ShotScreen icon using 200x200 source at smaller display size
            Group {
                if let shotScreenIcon = NSImage(named: "ShotScreenIcon_200x200") {
                    Image(nsImage: shotScreenIcon)
                        .resizable()
                        .aspectRatio(contentMode: .fit)
                        .frame(width: 100, height: 100)
                        .cornerRadius(16)
                } else if let bundle = Bundle.main.url(forResource: "images/ShotScreenIcon_200x200", withExtension: "png"),
                          let nsImage = NSImage(contentsOf: bundle) {
                    Image(nsImage: nsImage)
                        .resizable()
                        .aspectRatio(contentMode: .fit)
                        .frame(width: 100, height: 100)
                        .cornerRadius(16)
                } else {
                    // Fallback icon
                    Image(systemName: "exclamationmark.triangle.fill")
                        .font(.system(size: 64))
                        .foregroundColor(.orange)
                }
            }
            
            // Title
            Text("Trial Expired")
                .font(.largeTitle)
                .fontWeight(.bold)
            
            // Message
            Text("Your 7-day trial of ShotScreen has expired.\nPlease purchase a license to continue using the app.")
                .font(.body)
                .multilineTextAlignment(.center)
                .foregroundColor(.secondary)
            
            // Buttons - matching new style
            VStack(spacing: 12) {
                Button("Purchase License") {
                    openPurchaseURL()
                }
                .buttonStyle(.borderedProminent)
                
                Button("Enter License Key") {
                    licenseManager.showLicenseEntryDialog()
                }
                .buttonStyle(.bordered)
                
                Button("Quit ShotScreen") {
                    NSApplication.shared.terminate(nil)
                }
                .buttonStyle(.bordered)
                .foregroundColor(.red)
            }
        }
        .padding(40)
        .frame(width: 400, height: 350)
        .background(Color(NSColor.windowBackgroundColor))
    }
    
    private func openPurchaseURL() {
        // ShotScreen Gumroad license product
        if let url = URL(string: "https://roodenrijs.gumroad.com/l/uxexr") {
            NSWorkspace.shared.open(url)
        }
    }
}

#Preview {
    LicenseEntryView()
}