//  HotkeyBindings.swift
//  GreenshotMac
//
//  Maps the four capture actions onto global hotkeys and keeps them registered.

import AppKit

enum HotkeyAction: String, CaseIterable {
    case region
    case window
    case fullscreen
    case lastRegion

    var title: String {
        switch self {
        case .region: return "Capture region"
        case .window: return "Capture window"
        case .fullscreen: return "Capture full screen"
        case .lastRegion: return "Capture last region"
        }
    }

    var defaultsKey: String {
        switch self {
        case .region: return Configuration.Keys.hotkeyRegion
        case .window: return Configuration.Keys.hotkeyWindow
        case .fullscreen: return Configuration.Keys.hotkeyFullscreen
        case .lastRegion: return Configuration.Keys.hotkeyLastRegion
        }
    }

    var defaultSpec: HotkeySpec {
        switch self {
        case .region: return DefaultHotkeys.region
        case .window: return DefaultHotkeys.window
        case .fullscreen: return DefaultHotkeys.fullscreen
        case .lastRegion: return DefaultHotkeys.lastRegion
        }
    }
}

final class HotkeyBindings {
    static let shared = HotkeyBindings()

    private var registrations: [HotkeyAction: UInt32] = [:]

    private init() {}

    func spec(for action: HotkeyAction) -> HotkeySpec {
        Configuration.shared.hotkey(forKey: action.defaultsKey, default: action.defaultSpec)
    }

    func set(_ spec: HotkeySpec, for action: HotkeyAction) {
        Configuration.shared.setHotkey(spec, forKey: action.defaultsKey)
        registerAll()
        NotificationCenter.default.post(name: .hotkeysChanged, object: nil)
    }

    func registerAll() {
        for (_, id) in registrations { HotkeyManager.shared.unregister(id) }
        registrations.removeAll()

        for action in HotkeyAction.allCases {
            let spec = self.spec(for: action)
            guard !spec.isEmpty else { continue }
            if let id = HotkeyManager.shared.register(spec, handler: { HotkeyBindings.perform(action) }) {
                registrations[action] = id
            }
        }
    }

    static func perform(_ action: HotkeyAction) {
        Task { @MainActor in
            switch action {
            case .region: CaptureCoordinator.shared.captureRegion()
            case .window: CaptureCoordinator.shared.captureWindow()
            case .fullscreen: CaptureCoordinator.shared.captureFullscreen()
            case .lastRegion: CaptureCoordinator.shared.captureLastRegion()
            }
        }
    }
}

extension Notification.Name {
    static let hotkeysChanged = Notification.Name("GreenshotMacHotkeysChanged")
}