using System;
using System.Collections.Generic;
using Robust.Client.Audio.Sources;
using Robust.Client.Graphics;
using Robust.Client.UserInterface.Controls;
using Robust.Client.UserInterface.CustomControls;
using Robust.Shared;
using Robust.Shared.Audio.Sources;
using Robust.Shared.Log;
using Robust.Shared.Map;
using Robust.Shared.Maths;

namespace Robust.Client.UserInterface
{
    [NotContentImplementable]
    public partial interface IUserInterfaceManager
    {
        void InitializeTesting();

        InterfaceTheme ThemeDefaults { get; }

        /// <summary>
        ///     Default style sheet that applies to all controls
        ///     that do not have a more specific style sheet via <see cref="Control.Stylesheet"/>.
        /// </summary>
        Stylesheet? Stylesheet { get; set; }

        /// <summary>
        /// A control can have "keyboard focus" separate from ControlFocused, obtained when calling
        /// Control.GrabKeyboardFocus. Corresponding events in Control are KeyboardFocusEntered/Exited
        /// </summary>
        Control? KeyboardFocused { get; }

        /// <summary>
        /// A control gets "ControlFocused" when a mouse button (or any KeyBinding which has CanFocus = true) is
        /// pressed down on the control. While it is focused, it will receive mouse hover events and the corresponding
        /// keyup event if it still has focus when that occurs (it will NOT receive the keyup if focus has
        /// been taken by another control). Focus is removed when a different control takes focus
        /// (such as by pressing a different mouse button down over a different control) or when the keyup event
        /// happens. When focus is lost on a control, it always fires Control.ControlFocusExited.
        /// </summary>
        Control? ControlFocused { get; set; }
        public void PostInitialize();

        ViewportContainer MainViewport { get; }

        LayoutContainer StateRoot { get; }

        LayoutContainer WindowRoot { get; }

        LayoutContainer PopupRoot { get; }

        PopupContainer ModalRoot { get; }

        Control? CurrentlyHovered { get; }

        /// <summary>
        ///     Gets the default UIScale that we will use if <see cref="CVars.DisplayUIScale"/> gets set to 0.
        ///     Based on the OS-assigned window scale factor.
        /// </summary>
        float DefaultUIScale { get; }

        /// <summary>
        ///     The root control for the main game window.
        /// </summary>
        WindowRoot RootControl { get; }

        IDebugMonitors DebugMonitors { get; }

        void Popup(string contents, string? title = null, bool clipboardButton = true);

        Control? MouseGetControl(ScreenCoordinates coordinates);

        /// <summary>
        ///     Gets the mouse position in UI space, accounting for <see cref="UIScale"/>.
        /// </summary>
        ScreenCoordinates MousePositionScaled { get; }

        ScreenCoordinates ScreenToUIPosition(ScreenCoordinates coordinates);

        /// <summary>
        ///     Give a control keyboard focus, releasing focus on the currently focused control (if any).
        /// </summary>
        /// <param name="control">The control to give keyboard focus to.</param>
        /// <exception cref="ArgumentNullException">Thrown if <see cref="control"/> is <c>null</c>.</exception>
        /// <exception cref="ArgumentException">
        ///     Thrown if <see cref="control"/> has <see cref="Control.CanKeyboardFocus"/> <c>false</c>.
        /// </exception>
        void GrabKeyboardFocus(Control control);

        /// <summary>
        ///     Release keyboard focus from the currently focused control, if any.
        /// </summary>
        void ReleaseKeyboardFocus();

        /// <summary>
        ///     Conditionally release keyboard focus if <see cref="ifControl"/> has keyboard focus.
        /// </summary>
        /// <exception cref="ArgumentNullException">
        ///     Thrown if <see cref="ifControl"/> is <c>null</c>.
        /// </exception>
        /// <seealso cref="ReleaseKeyboardFocus()"/>
        void ReleaseKeyboardFocus(Control ifControl);

        /// <summary>
        ///     Cursor automatically used when the mouse is not over any UI control.
        /// </summary>
        ICursor? WorldCursor { get; set; }

        void PushModal(Control modal);
        WindowRoot CreateWindowRoot(IClydeWindow window);
        void DestroyWindowRoot(IClydeWindow window);

        /// <summary>
        /// Get the UI root associated with a window.
        /// </summary>
        /// <returns>Null if the window has no UI root.</returns>
        WindowRoot? GetWindowRoot(IClydeWindow window);

        IEnumerable<UIRoot> AllRoots { get; }

        event Action<PostDrawUIRootEventArgs> OnPostDrawUIRoot;

        void DeferAction(Action action);

        public event Action<Control>? OnKeyBindDown;

        void SetClickSound(IAudioSource? source);

        /// <summary>
        /// Plays the UI click sound if relevant
        /// </summary>
        void ClickSound();

        void SetHoverSound(IAudioSource? source);

        /// <summary>
        /// Plays the UI hover sound if relevant.
        /// </summary>
        void HoverSound();

        /// <summary>
        /// Sets <see cref="CurrentlyHovered"/> to the given control.
        /// </summary>
        void SetHovered(Control? control);

        /// <summary>
        /// Forces <see cref="CurrentlyHovered"/> to get updated. This is done automatically when the mouse is moved,
        /// but not necessarily a new or existing control is rearranged.
        /// </summary>
        void UpdateHovered();

        /// <summary>
        /// Render a control and all of its children.
        /// </summary>
        void RenderControl(in Control.ControlRenderArguments args, Control control);

        /// <summary>
        /// Render a control and all of its children.
        /// </summary>
        void RenderControl(IRenderHandle handle, Control control, Vector2i position);

        /// <summary>
        /// Sawmill for use by controls.
        /// </summary>
        /// <remarks>
        /// Exists so that control don't have to inject dependencies or otherwise obtain an <see cref="ILogManager"/> instance just to log errors.
        /// </remarks>
        ISawmill ControlSawmill { get; }

        /// <summary>
        /// Get the UI root responsible for the current mouse position.
        /// </summary>
        /// <remarks>
        /// This is useful to open popups or similar on the current active window.
        /// </remarks>
        UIRoot GetRootForMouse();
    }

    public readonly struct PostDrawUIRootEventArgs
    {
        public readonly UIRoot Root;
        public readonly DrawingHandleScreen DrawingHandle;

        public PostDrawUIRootEventArgs(UIRoot root, DrawingHandleScreen drawingHandle)
        {
            Root = root;
            DrawingHandle = drawingHandle;
        }
    }
}