using System;
using System.Collections.Generic;
using Coroutine;
using Microsoft.Xna.Framework;
using Microsoft.Xna.Framework.Graphics;
using MLEM.Font;
using MLEM.Input;
using MLEM.Startup;
using MLEM.Textures;
using MLEM.Ui;
using MLEM.Ui.Elements;
using MLEM.Ui.Style;

namespace Examples {
    public class GameImpl : MlemGame {

        private Texture2D testTexture;
        private NinePatch testPatch;

        public GameImpl() {
            this.IsMouseVisible = true;
        }

        protected override void LoadContent() {
            this.testTexture = LoadContent<Texture2D>("Textures/Test");
            this.testPatch = new NinePatch(new TextureRegion(this.testTexture, 0, 8, 24, 24), 8);
            base.LoadContent();

            var style = new UiStyle {
                Font = new GenericSpriteFont(LoadContent<SpriteFont>("Fonts/TestFont")),
                TextScale = 0.2F,
                PanelTexture = this.testPatch,
                ButtonTexture = new NinePatch(new TextureRegion(this.testTexture, 24, 8, 16, 16), 4),
                TextFieldTexture = new NinePatch(new TextureRegion(this.testTexture, 24, 8, 16, 16), 4),
                ButtonHoveredColor = Color.LightGray,
                TextFieldHoveredColor = Color.LightGray
            };
            var untexturedStyle = this.UiSystem.Style;
            this.UiSystem.Style = style;
            this.UiSystem.GlobalScale = 5;

            var root = new Panel(Anchor.Center, new Vector2(100, 120), Point.Zero, true);
            this.UiSystem.Add("Test", root);

            root.AddChild(new Paragraph(Anchor.AutoLeft, 1, "This is a test text that is hopefully long enough to cover at least a few lines, otherwise it would be very sad."));
            var image = root.AddChild(new Image(Anchor.AutoCenter, new Vector2(20, 20), new TextureRegion(this.testTexture, 0, 0, 8, 8)) {IsHidden = true});
            root.AddChild(new Button(Anchor.AutoCenter, new Vector2(1, 15), "Test Button") {
                OnClicked = (element, button) => {
                    if (button == MouseButton.Left)
                        image.IsHidden = !image.IsHidden;
                }
            });
            root.AddChild(new Button(Anchor.AutoCenter, new Vector2(1, 15), "Change Style") {
                OnClicked = (element, button) => {
                    if (button == MouseButton.Left)
                        this.UiSystem.Style = this.UiSystem.Style is UntexturedStyle ? style : untexturedStyle;
                },
                HasCustomStyle = true,
                Texture = this.testPatch,
                HoveredColor = Color.LightGray
            });
            root.AddChild(new TextField(Anchor.AutoLeft, new Vector2(1, 15)));

            root.AddChild(new VerticalSpace(3));
            root.AddChild(new Button(Anchor.AutoLeft, new Vector2(15), "+") {
                OnClicked = (element, button) => {
                    if (element.Root.Scale < 2)
                        element.Root.Scale += 0.1F;
                }
            });
            root.AddChild(new Button(Anchor.AutoInline, new Vector2(15), "-") {
                OnClicked = (element, button) => {
                    if (element.Root.Scale > 0.5F)
                        element.Root.Scale -= 0.1F;
                }
            });
            root.AddChild(new Button(Anchor.AutoInline, new Vector2(30, 15), "Woop") {
                OnClicked = (element, button) => CoroutineHandler.Start(Woop(element))
            });
        }

        private static IEnumerator<Wait> Woop(Element element) {
            var angle = 0;
            var startScale = element.Root.Scale;
            while (angle < 180) {
                element.Root.Scale = startScale + (float) Math.Sin(MathHelper.ToRadians(angle));
                angle++;
                yield return new WaitSeconds(0.01F);
            }
        }

        protected override void Draw(GameTime gameTime) {
            this.GraphicsDevice.Clear(Color.Black);
            base.Draw(gameTime);
        }

    }
}