using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

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

namespace BehaviourDemoPort
{
    enum EditMode
    {
        Select,
        Move,
    }

    class SceneEditor
    {
        EditMode editMode;

        public SceneEditor()
        {
            Keys[] allKeys = (Keys[])Enum.GetValues(typeof(Keys));
            foreach (var key in allKeys)
                KeyboardInput.AddKey(key);

            KeyboardInput.KeyRelease += new KeyHandler(KeyboardInput_KeyRelease);

            MouseInput.MouseMove += new MouseMoveHandler(MouseInput_MouseMove);
            MouseInput.MouseDown += new MouseClickHandler(MouseInput_MouseDown);
            MouseInput.MouseUp += new MouseClickHandler(MouseInput_MouseUp);
        }

        void KeyboardInput_KeyRelease(Keys key, KeyboardState keyState)
        {
            if (key == Keys.Q)
            {
                this.editMode = EditMode.Select;
            }
            else if (key == Keys.W)
            {
                this.editMode = EditMode.Move;
            }
            else if (key == Keys.Delete)
            {
                foreach (var actor in Actor.Selection)
                {
                    actor.Delete();
                }
                Actor.Selection.Clear();
            }
            else if (key == Keys.C && Actor.Selection.Count >= 2)
            {
                for (int i = 1; i < Actor.Selection.Count; i++)
                {
                    Node nodeA = Actor.Selection[i - 1] as Node;
                    Node nodeB = Actor.Selection[i] as Node;

                    if (nodeA != null & nodeB != null)
                        nodeA.BidiConnect(nodeB);
                }
            }
            else if (key == Keys.X && Actor.Selection.Count >= 2)
            {
                for (int i = 1; i < Actor.Selection.Count; i++)
                {
                    Node nodeA = Actor.Selection[i - 1] as Node;
                    Node nodeB = Actor.Selection[i] as Node;

                    if (nodeA != null & nodeB != null)
                        nodeA.BidiDisconnect(nodeB);
                }
            }
        }

        void MouseInput_MouseMove(Vector2 position, Vector2 movement)
        {
            if (this.editMode == EditMode.Move && MouseInput.IsLeftButtonDown)
            {
                foreach (var actor in Actor.Selection)
                {
                    actor.Position += movement;
                }
            }
        }

        void MouseInput_MouseDown(Vector2 position)
        {
            if (KeyboardInput.IsShiftDown)
            {
                Node node = new Node();
                node.Position = position;
                Node lastNode = Actor.LastSelected as Node;
                if (lastNode != null)
                {
                    node.BidiConnect(lastNode);
                }

                Actor.Selection.Clear();
                node.Select();

                return;
            }

            Actor actor = GetActorAt(position);
            if (actor != null)
            {
                if (!actor.IsSelected && !KeyboardInput.IsControlDown)
                    Actor.Selection.Clear();
                if (KeyboardInput.IsControlDown)
                    actor.ToggleSelect();
                else
                    actor.Select();
            }
            else if (!KeyboardInput.IsControlDown)
                Actor.Selection.Clear();
        }

        void MouseInput_MouseUp(Vector2 position)
        {
            if (Actor.Selection.Count > 0 && !KeyboardInput.IsControlDown)
            {
                Actor.Selection.Clear();

                Actor actor = GetActorAt(position);
                if (actor != null)
                    actor.Select();
            }
        }

        Actor GetActorAt(Vector2 position)
        {
            for (int i = Actor.Actors.Count -1; i >= 0; i--)
            {
                Actor actor = Actor.Actors[i];
                if (Vector2.Distance(actor.Position, position) < actor.Radius)
                {
                    return actor;
                }
            }
            return null;
        }


        public void Draw(SpriteBatch SpriteBatch)
        {
            string text = String.Format("mode: {0}", this.editMode);
            SpriteBatch.DrawString(Style.FontLarge, text, new Vector2(10, 10), Color.White);
        }
    }
}