macbackend/Sources/Core/Window/Window.swift

//
//  Window.swift
//  MacBackend
//
//  Created by david-swift on 14.09.23.
//

import AppKit

/// A structure representing an application window type.
///
/// Note that it may be possible to open multiple instances of a window at the same time.
public struct Window: MacSceneElement {

    /// The window's identifier.
    public var id: String
    /// The window's content.
    var content: (MacWindow) -> Body
    /// Whether an instance of the window type should be opened when the app is starting up.
    var `open`: Int
    /// The window's title.
    var title: String
    /// Whether the window is miniaturizable.
    var miniaturizable = true
    /// Whether the window is resizable.
    var resizable = true
    /// The window's width.
    var width: Binding<Int>?
    /// The window's height.
    var height: Binding<Int>?

    // swiftlint:disable function_default_parameter_at_end
    /// Create a window type with a certain identifier and user interface.
    /// - Parameters:
    ///   - id: The identifier.
    ///   - open: The number of instances of the window type when the app is starting.
    ///   - content: The window's content.
    ///   - title: The window's title.
    public init(
        _ title: String = "",
        id: String,
        `open`: Int = 1,
        @ViewBuilder content: @escaping (MacWindow) -> Body
    ) {
        self.title = title
        self.content = content
        self.id = id
        self.open = open
    }
    // swiftlint:enable function_default_parameter_at_end

    /// The window type.
    public struct MacWindow {

        /// The window.
        var window: NSWindow

        /// Close the window.
        public func close() {
            window.close()
        }

    }

    /// Set up the initial scene storages.
    /// - Parameter app: The app storage.
    public func setupInitialContainers<Storage>(app: Storage) where Storage: AppStorage {
        for _ in 0..<open {
            let container = container(app: app)
            container.show()
            app.storage.sceneStorage.append(container)
        }
    }

    /// The scene storage.
    /// - Parameter app: The app storage.
    public func container<Storage>(app: Storage) -> SceneStorage where Storage: AppStorage {
        let window = NSWindow()
        let storage = SceneStorage(id: id, pointer: window) {
            window.makeKeyAndOrderFront(nil)
        }
        NotificationCenter.default
            .addObserver(forName: NSWindow.willCloseNotification, object: window, queue: nil) { _ in
                storage.destroy = true
            }
        let content = content(.init(window: window))
            .storage(data: .init(sceneStorage: storage, appStorage: app), type: MacMainView.self)
        if let pointer = content.pointer as? NSView {
            window.contentView = pointer
        }
        storage.content[.mainContent] = [content]
        window.styleMask = [.titled, .closable, .fullSizeContentView, .resizable, .miniaturizable]
        update(storage, app: app, updateProperties: true)
        window.setFrame(
            .init(origin: .zero, size: .init(width: width?.wrappedValue ?? -1, height: height?.wrappedValue ?? -1)),
            display: true
        )
        return storage
    }

    /// Update the stored content.
    /// - Parameters:
    ///     - storage: The storage to update.
    ///     - app: The app storage.
    ///     - updateProperties: Whether to update the view's properties.
    public func update<Storage>(
        _ storage: SceneStorage,
        app: Storage,
        updateProperties: Bool
    ) where Storage: AppStorage {
        guard let window = storage.pointer as? NSWindow else {
            return
        }
        if let content = storage.content[.mainContent]?.first {
            self.content(.init(window: window)).updateStorage(
                content,
                data: .init(sceneStorage: storage, appStorage: app),
                updateProperties: updateProperties,
                type: MacMainView.self
            )
        }
        guard updateProperties else {
            return
        }
        let previousState = storage.previousState as? Self
        if previousState?.title != title {
            window.title = title
        }
        if previousState?.miniaturizable != miniaturizable {
            if miniaturizable {
                window.styleMask.insert(.miniaturizable)
            } else {
                window.styleMask.remove(.miniaturizable)
            }
        }
        if previousState?.resizable != resizable {
            if resizable {
                window.styleMask.insert(.resizable)
            } else {
                window.styleMask.remove(.resizable)
            }
        }
        storage.previousState = self
    }

    /// The window's width and height.
    /// - Parameters:
    ///   - width: The width.
    ///   - height: The height.
    /// - Returns: The window.
    public func frame(width: Binding<Int>? = nil, height: Binding<Int>? = nil) -> Self {
        var newSelf = self
        newSelf.width = width
        newSelf.height = height
        return newSelf
    }

    /// Whether the window is miniaturizable.
    /// - Parameter miniaturizable: Whether the window is miniaturizable.
    /// - Returns: The window.
    public func miniaturizable(_ miniaturizable: Bool = true) -> Self {
        var newSelf = self
        newSelf.miniaturizable = miniaturizable
        return newSelf
    }

    /// Whether the window is resizable.
    /// - Parameter resizable: Whether the window is resizable.
    /// - Returns: The window.
    public func resizable(_ resizable: Bool = true) -> Self {
        var newSelf = self
        newSelf.resizable = resizable
        return newSelf
    }

}

/// The window type.
public typealias MacWindow = Window.MacWindow