using Microsoft.Xna.Framework;
using Microsoft.Xna.Framework.Graphics;
using Microsoft.Xna.Framework.Input;

namespace Barotrauma
{
    public class GUIButton : GUIComponent
    {
        protected GUITextBlock textBlock;
        protected GUIFrame frame;

        public delegate bool OnClickedHandler(GUIButton button, object obj);
        public OnClickedHandler OnClicked;

        public delegate bool OnPressedHandler();
        public OnPressedHandler OnPressed;

        public bool CanBeSelected = true;

        private bool enabled;

        public bool Enabled 
        { 
            get
            {
                return enabled;
            }

            set
            {
                if (value == enabled) return;

                enabled = value;
                frame.Color = enabled ? color : Color.Gray * 0.7f;
            }
        }

        public override Color Color
        {
            get { return base.Color; }
            set
            {
                base.Color = value;
                frame.Color = value;
            }
        }

        public override Color HoverColor
        {
            get { return base.HoverColor; }
            set
            {
                base.HoverColor = value;
                frame.HoverColor = value;
            }
        }

        public override Color SelectedColor
        {
            get
            {
                return base.SelectedColor;
            }
            set
            {
                base.SelectedColor = value;
                frame.SelectedColor = value;
            }
        }

        public override Color OutlineColor
        {
            get { return base.OutlineColor; }
            set
            {
                base.OutlineColor = value;
                if (frame != null) frame.OutlineColor = value;
            }
        }

        public Color TextColor
        {
            get { return textBlock.TextColor; }
            set { textBlock.TextColor = value; }
        }

        public override ScalableFont Font
        {
            get
            {
                return (textBlock==null) ? GUI.Font : textBlock.Font;
            }
            set
            {
                base.Font = value;
                if (textBlock != null) textBlock.Font = value;                
            }
        }
        
        public string Text
        {
            get { return textBlock.Text; }
            set { textBlock.Text = value; }
        }

        public override string ToolTip
        {
            get
            {
                return base.ToolTip;
            }
            set
            {
                textBlock.ToolTip = value;
                base.ToolTip = value;
            }
        }

        public override Rectangle Rect
        {
            get
            {
                return rect;
            }
            set
            {
                base.Rect = value;

                frame.Rect = new Rectangle(value.X, value.Y, frame.Rect.Width, frame.Rect.Height);
                textBlock.Rect = value;
            }
        }

        public bool Selected { get; set; }

        public GUIButton(Rectangle rect, string text, string style, GUIComponent parent = null)
            : this(rect, text, null, Alignment.Left, style, parent)
        {
        }

        public GUIButton(Rectangle rect, string text, Alignment alignment, string style, GUIComponent parent = null)
            : this(rect, text, null, alignment, style, parent)
        {
        }

        public GUIButton(Rectangle rect, string text, Color? color, string style, GUIComponent parent = null)
            : this(rect, text, color, (Alignment.Left | Alignment.Top), style, parent)
        {
        }

        public GUIButton(Rectangle rect, string text, Color? color, Alignment alignment, string style = "", GUIComponent parent = null)
            : this(rect, text, color, alignment, Alignment.Center, style, parent)
        {

        }

        public GUIButton(Rectangle rect, string text, Color? color, Alignment alignment, Alignment textAlignment, string style = "", GUIComponent parent = null)
            : base(style)
        {
            this.rect = rect;
            if (color != null) this.color = (Color)color;
            this.alignment = alignment;

            if (parent != null) parent.AddChild(this);

            frame = new GUIFrame(Rectangle.Empty, style, this);
            GUI.Style.Apply(frame, style == "" ? "GUIButton" : style);

            textBlock = new GUITextBlock(Rectangle.Empty, text,
                Color.Transparent, (this.style == null) ? Color.Black : this.style.textColor,
                textAlignment, null, this);
            GUI.Style.Apply(textBlock, style, this);

            Enabled = true;
        }

        public override void ApplyStyle(GUIComponentStyle style)
        {
            base.ApplyStyle(style);

            if (frame != null) frame.ApplyStyle(style);
            if (textBlock != null) textBlock.ApplyStyle(style);
        }

        public override void Draw(SpriteBatch spriteBatch)
        {
            if (!Visible) return;
            
            DrawChildren(spriteBatch);
        }
        
        public override void Update(float deltaTime)
        {
            if (!Visible) return;
            base.Update(deltaTime);
            if (rect.Contains(PlayerInput.MousePosition) && CanBeSelected && Enabled && (MouseOn == null || MouseOn == this || IsParentOf(MouseOn)))
            {
                state = ComponentState.Hover;
                if (PlayerInput.LeftButtonHeld())
                {
                    if (OnPressed != null)
                    {
                        if (OnPressed()) state = ComponentState.Pressed;
                    }
                }
                else if (PlayerInput.LeftButtonClicked())
                {
                    GUI.PlayUISound(GUISoundType.Click);
                    if (OnClicked != null)
                    {
                        if (OnClicked(this, UserData) && CanBeSelected) state = ComponentState.Selected;
                    }
                    else
                    {
                        Selected = !Selected;
                        // state = state == ComponentState.Selected ? ComponentState.None : ComponentState.Selected;
                    }
                }
            }
            else
            {
                state = Selected ? ComponentState.Selected : ComponentState.None;
            }
            frame.State = state;
        }
    }
}