import AppKit
import ConjureKit

@main
@MainActor
struct ConjureApp {
    static func main() {
        let application = NSApplication.shared
        let delegate = ApplicationDelegate()
        application.delegate = delegate
        application.setActivationPolicy(.accessory)
        application.mainMenu = makeMainMenu(delegate: delegate)

        // NSApplication holds its delegate weakly.
        withExtendedLifetime(delegate) {
            application.run()
        }
    }

    private static func makeMainMenu(delegate: ApplicationDelegate) -> NSMenu {
        let menu = NSMenu()
        let applicationItem = NSMenuItem(title: "Conjure", action: nil, keyEquivalent: "")
        let applicationMenu = NSMenu(title: "Conjure")
        applicationItem.submenu = applicationMenu
        menu.addItem(applicationItem)

        applicationMenu.addItem(
            withTitle: "About Conjure",
            action: #selector(NSApplication.orderFrontStandardAboutPanel(_:)),
            keyEquivalent: ""
        )
        let settings = applicationMenu.addItem(
            withTitle: "Settings…",
            action: #selector(ApplicationDelegate.showSettings(_:)),
            keyEquivalent: ","
        )
        settings.target = delegate
        applicationMenu.addItem(.separator())
        applicationMenu.addItem(
            withTitle: "Hide Conjure",
            action: #selector(NSApplication.hide(_:)),
            keyEquivalent: "h"
        )
        let hideOthers = applicationMenu.addItem(
            withTitle: "Hide Others",
            action: #selector(NSApplication.hideOtherApplications(_:)),
            keyEquivalent: "h"
        )
        hideOthers.keyEquivalentModifierMask = [.command, .option]
        applicationMenu.addItem(
            withTitle: "Show All",
            action: #selector(NSApplication.unhideAllApplications(_:)),
            keyEquivalent: ""
        )
        applicationMenu.addItem(.separator())
        applicationMenu.addItem(
            withTitle: "Quit Conjure",
            action: #selector(NSApplication.terminate(_:)),
            keyEquivalent: "q"
        )

        let fileItem = NSMenuItem(title: "File", action: nil, keyEquivalent: "")
        let fileMenu = NSMenu(title: "File")
        fileItem.submenu = fileMenu
        menu.addItem(fileItem)
        fileMenu.addItem(withTitle: "Close Window", action: #selector(NSWindow.performClose(_:)), keyEquivalent: "w")

        let editItem = NSMenuItem(title: "Edit", action: nil, keyEquivalent: "")
        let editMenu = NSMenu(title: "Edit")
        editItem.submenu = editMenu
        menu.addItem(editItem)
        editMenu.addItem(withTitle: "Cut", action: #selector(NSText.cut(_:)), keyEquivalent: "x")
        editMenu.addItem(withTitle: "Undo", action: Selector(("undo:")), keyEquivalent: "z")
        let redo = editMenu.addItem(withTitle: "Redo", action: Selector(("redo:")), keyEquivalent: "z")
        redo.keyEquivalentModifierMask = [.command, .shift]
        editMenu.addItem(withTitle: "Copy", action: #selector(NSText.copy(_:)), keyEquivalent: "c")
        editMenu.addItem(withTitle: "Paste", action: #selector(NSText.paste(_:)), keyEquivalent: "v")
        editMenu.addItem(.separator())
        editMenu.addItem(withTitle: "Select All", action: #selector(NSText.selectAll(_:)), keyEquivalent: "a")

        let windowItem = NSMenuItem(title: "Window", action: nil, keyEquivalent: "")
        let windowMenu = NSMenu(title: "Window")
        windowItem.submenu = windowMenu
        menu.addItem(windowItem)
        windowMenu.addItem(withTitle: "Minimize", action: #selector(NSWindow.performMiniaturize(_:)), keyEquivalent: "m")
        windowMenu.addItem(withTitle: "Zoom", action: #selector(NSWindow.performZoom(_:)), keyEquivalent: "")
        windowMenu.addItem(.separator())
        windowMenu.addItem(withTitle: "Bring All to Front", action: #selector(NSApplication.arrangeInFront(_:)), keyEquivalent: "")
        NSApplication.shared.windowsMenu = windowMenu
        return menu
    }
}

@MainActor
private final class ApplicationDelegate: NSObject, NSApplicationDelegate {
    private let uninstaller = ApplicationUninstaller()
    private lazy var launcher = LauncherWindowController(uninstaller: uninstaller)
    private lazy var shortcuts = GlobalShortcuts { [weak self] destination in
        switch destination {
        case .launcher: self?.launcher.toggle()
        case .command(let command): self?.launcher.toggle(command: command)
        }
    }
    private lazy var settings = makeSettings()

    private func makeSettings() -> SettingsWindowController {
        let controller = SettingsWindowController(shortcuts: shortcuts)
        controller.retryUninstallRecovery = { [uninstaller] in await uninstaller.recover() }
        return controller
    }
    private var startupError = ThemePalette.configurationError
    private var startupRecoveryMessage: String?

    private var isLoginLaunch: Bool {
        let event = NSAppleEventManager.shared().currentAppleEvent
        return event?.eventID == kAEOpenApplication
            && event?.paramDescriptor(forKeyword: keyAEPropData)?.enumCodeValue == keyAELaunchedAsLogInItem
    }

    func applicationDidFinishLaunching(_ notification: Notification) {
        let menu = NSMenu()
        let settingsItem = menu.addItem(withTitle: "Settings…", action: #selector(showSettings(_:)), keyEquivalent: ",")
        settingsItem.target = self
        menu.addItem(.separator())
        let quitItem = menu.addItem(withTitle: "Quit Conjure", action: #selector(NSApplication.terminate(_:)), keyEquivalent: "q")
        quitItem.target = NSApplication.shared
        launcher.window?.contentView?.menu = menu
        let loginLaunch = isLoginLaunch
        Task {
            let report = await uninstaller.recover()
            guard !report.messages.isEmpty else { return }
            startupRecoveryMessage = report.messages.joined(separator: "\n")
            settings.setUninstallRecoveryReport(report)
            if !loginLaunch { showSettings(nil) }
        }
        if !isLoginLaunch {
            launcher.present()
        }
        let shortcutErrors = shortcuts.start()
        startupError = ([startupError].compactMap { $0 } + shortcutErrors).joined(separator: "\n")
        if startupError?.isEmpty == true { startupError = nil }
        if startupError != nil && !loginLaunch { showSettings(nil) }
    }

    func applicationShouldHandleReopen(_ sender: NSApplication, hasVisibleWindows: Bool) -> Bool {
        guard !isLoginLaunch else { return false }
        launcher.present()
        if startupError != nil || startupRecoveryMessage != nil {
            showSettings(nil)
        }
        return false
    }

    @objc func showSettings(_ sender: Any?) {
        settings.present(error: startupError)
        startupError = nil
        startupRecoveryMessage = nil
    }

    func applicationShouldTerminate(_ sender: NSApplication) -> NSApplication.TerminateReply {
        launcher.saveNotes() ? .terminateNow : .terminateCancel
    }
    func applicationWillTerminate(_ notification: Notification) {
        shortcuts.stop()
    }

    func applicationShouldTerminateAfterLastWindowClosed(_ sender: NSApplication) -> Bool {
        false
    }
}