/******************************************************************************/
/*!
\file Game1.cs
\author Kevin Carey

    Core XNA game class
    Copyright © 2007 DigiPen(USA) Corporation. All rights reserved.

*/
/******************************************************************************/


#region Using Statements
using System;
using System.Collections.Generic;
using Microsoft.Xna.Framework;
using Microsoft.Xna.Framework.Audio;
using Microsoft.Xna.Framework.Content;
using Microsoft.Xna.Framework.Graphics;
using Microsoft.Xna.Framework.Input;
using Microsoft.Xna.Framework.Storage;
#endregion

namespace Shooting_Range
{
    /// <summary>
    /// This is the main type for your game
    /// Called Game1 by default in XNA.  Never changed it.
    /// </summary>
    public class Game1 : Microsoft.Xna.Framework.Game
    {
        // Game1 Members
        GameFunctions gameFunctions;
        public KeyboardState previousKeyboardState;
        public MouseState previousMouseState;

        // Game1 constructor
        public Game1()
        {
            // Initialize members (stored in a class to make this file prettier!)
            gameFunctions = new GameFunctions(this);
        }


        /// <summary>
        /// Allows the game to perform any initialization it needs to before starting to run.
        /// This is where it can query for any required services and load any non-graphic
        /// related content.  Calling base.Initialize will enumerate through any components
        /// and initialize them as well.
        /// </summary>
        protected override void Initialize()
        {
            // Set the title
            Window.Title = "Egnar 85521C";

            // Set the mouse position
            Mouse.SetPosition(gameFunctions.Graphics.DeviceManager.GraphicsDevice.Viewport.Width / 2, 
                              gameFunctions.Graphics.DeviceManager.GraphicsDevice.Viewport.Height / 2);

            // Set the input states
            previousMouseState = Mouse.GetState();
            previousKeyboardState = Keyboard.GetState();

            // Initialize the game members
            gameFunctions.Initialize();

            base.Initialize();
        }

        /// <summary>
        /// Load your graphics content.  If loadAllContent is true, you should
        /// load content from both ResourceManagementMode pools.  Otherwise, just
        /// load ResourceManagementMode. Manual content.
        /// </summary>
        /// <param name="loadAllContent">Which type of content to load.</param>
        protected override void LoadGraphicsContent(bool loadAllContent)
        {
            if (loadAllContent)
            {
                gameFunctions.LoadGraphicsContent();
            }
        }


        /// <summary>
        /// Unload your graphics content.  If unloadAllContent is true, you should
        /// unload content from both ResourceManagementMode pools.  Otherwise, just
        /// unload ResourceManagementMode.Manual content.  Manual content will get
        /// Disposed by the GraphicsDevice during a Reset.
        /// </summary>
        /// <param name="unloadAllContent">Which type of content to unload.</param>
        protected override void UnloadGraphicsContent(bool unloadAllContent)
        {
            if (unloadAllContent)
            {
                // Unload game content
                gameFunctions.Graphics.Content.Unload();
                // Shutdown sounds
                gameFunctions.Sounds.Shutdown();
            }
        }


        /// <summary>
        /// Allows the game to run logic such as updating the world,
        /// checking for collisions, gathering input and playing audio.
        /// </summary>
        /// <param name="gameTime">Provides a snapshot of timing values.</param>
        protected override void Update(GameTime gameTime)
        {
            // Update based on input
            UpdateInput(gameTime.ElapsedGameTime);

            // Update the game
            gameFunctions.Update(gameTime.ElapsedGameTime);

            // Update the input states
            previousKeyboardState = Keyboard.GetState();
            previousMouseState = Mouse.GetState();

            base.Update(gameTime);
        }

        private void UpdateInput(TimeSpan deltaTime)
        {
            // Get the current input states
            KeyboardState currentKeyboardState = Keyboard.GetState();
            MouseState currentMouseState = Mouse.GetState();

            // If the Back button of Esc is pressed
            if (GamePad.GetState(PlayerIndex.One).Buttons.Back == ButtonState.Pressed ||
                (previousKeyboardState.IsKeyUp(Keys.Escape) && currentKeyboardState.IsKeyDown(Keys.Escape)))
            {
                switch (gameFunctions.State)
                {
                    // In the GAME state
                    case GameState.GAME:
                        // Shutdown the game state
                        gameFunctions.ShutdownGameState();
                        // Initialize the stats state
                        gameFunctions.InitStatsState();
                        break;

                    // In the STATS state
                    case GameState.STATS:
                        // Shutdon the stats state
                        gameFunctions.ShutdownStatsState();
                        // Initialize the menu state
                        gameFunctions.InitMenuState();
                        break;

                    // In the CREDITS state
                    case GameState.CREDITS:
                        // Shutdown the credits state
                        gameFunctions.ShutdownCreditsState();
                        // Initialize the menu state
                        gameFunctions.InitMenuState();
                        break;

                    // In the MENU state
                    case GameState.MENU:
                        // Exit the game
                        this.Exit();
                        break;
                }
            }

            // If the left mouse button is pressed
            if ((previousMouseState.LeftButton == ButtonState.Released) && (currentMouseState.LeftButton == ButtonState.Pressed))
            {
                switch (gameFunctions.State)
                {
                    // In the GAME state
                    case GameState.GAME:
                        // If able to shoot a bullet
                        if (gameFunctions.FailTimer == TimeSpan.MinValue)
                        {
                            // Spawn a bullet
                            gameFunctions.SpawnBullet();
                        }
                        break;

                    // In the other states
                    case GameState.MENU:
                    case GameState.STATS:
                    case GameState.CREDITS:
                        // Do nothing
                        break;
                }
            }

            // If the mouse position has changed
            if (previousMouseState.X != currentMouseState.X ||
                previousMouseState.Y != currentMouseState.Y)
            {
                // Adjust the camera
                gameFunctions.Graphics.CameraData.LookAtPositionX += currentMouseState.X - previousMouseState.X;
                gameFunctions.Graphics.CameraData.LookAtPositionY += previousMouseState.Y - currentMouseState.Y;

                // If not in the game state
                if (gameFunctions.State != GameState.GAME)
                {
                    // Move the cursor sprite
                    gameFunctions.CursorSprite.PositionX = currentMouseState.X;
                    gameFunctions.CursorSprite.PositionY = currentMouseState.Y;
                }
            }
        }

        /// <summary>
        /// This is called when the game should draw itself.
        /// </summary>
        /// <param name="gameTime">Provides a snapshot of timing values.</param>
        protected override void Draw(GameTime gameTime)
        {
            // Clear the screen to black
            gameFunctions.Graphics.DeviceManager.GraphicsDevice.Clear(Color.Black);

            // Draw!
            gameFunctions.Draw();

            base.Draw(gameTime);
        }
    }
}