/*
 * Ticker.cs
 * Authors:     August Zinsser
 * 
 * Copyright Matthew Belmonte 2007
 */


using System;
using System.Collections.Generic;
using System.Text;
using Microsoft.Xna.Framework;
using Microsoft.Xna.Framework.Graphics;
using Microsoft.Xna.Framework.Content;
using Nuclex.Fonts;


namespace tAC_Engine
{
    /// <summary>
    /// Displays text and/or pictures in various manners on top of all other graphics.
    /// This is uesful for outputting text to a HUD or displaying popup text or graphics.
    /// </summary>
    public static class Ticker
    {
        /// <summary>
        /// Defines the possible fonts to use with the text ticker
        /// </summary>
        public enum Font { Standard, Standard_Big, Space, Space_Big, InGame_Tiny };


        /// <summary>
        /// Holds the information necsesary to display message
        /// </summary>
        private class Message
        {
            public Vector2 Position = Vector2.Zero;
            public Vector2 Velocity = Vector2.Zero;
            public int Width = 0;
            public int Height = 0;
            public int ImageWidth = 0;
            public int ImageHeight = 0;
            public bool FadesIn = false;
            public bool FadesOut = false;
            public Color Tint = Color.White;
            public float CurOpacity = 1f;
            public float FinOpacity = 1f;
            public string Text = "";
            public float Lifetime = 0f;
            public Texture2D Image = null;
            public Ticker.Font Font = Ticker.Font.Standard;


            /// <summary>
            /// Draws this message to its own spritebatch
            /// </summary>
            public void Draw(SpriteBatch spriteBatch)
            {
                int padding = 0;
                if (Image != null)
                {
                    spriteBatch.Draw(Image, new Rectangle((int)Position.X - Width / 2 - 5 - ImageWidth / 2, (int)Position.Y - ImageHeight / 2, (int)ImageWidth, (int)ImageHeight), new Color(Tint.R, Tint.G, Tint.B, (byte)(255 * CurOpacity)));
                    padding = 5;
                }

                switch (Font)
                {
                    case Ticker.Font.Standard:
                        GenericBaseApplication.GameManager.StandardFont.DrawString(new Vector2((int)Position.X - Width / 2 + padding + ImageWidth / 2, (int)Position.Y + Height / 2), Text, new Color(Tint.R, Tint.G, Tint.B, (byte)(255 * CurOpacity)));
                        break;

                    case Ticker.Font.Standard_Big:
                        GenericBaseApplication.GameManager.StandardFontBig.DrawString(new Vector2((int)Position.X - Width / 2 + padding + ImageWidth / 2, (int)Position.Y + Height / 2), Text, new Color(Tint.R, Tint.G, Tint.B, (byte)(255 * CurOpacity)));
                        break;

                    case Ticker.Font.Space:
                        GenericBaseApplication.GameManager.SpaceFont.DrawString(new Vector2((int)Position.X - Width / 2 + padding + ImageWidth / 2, (int)Position.Y + Height / 2), Text, new Color(Tint.R, Tint.G, Tint.B, (byte)(255 * CurOpacity)));
                        break;

                    case Ticker.Font.Space_Big:
                        GenericBaseApplication.GameManager.SpaceFontBig.DrawString(new Vector2((int)Position.X - Width / 2 + padding + ImageWidth / 2, (int)Position.Y + Height / 2), Text, new Color(Tint.R, Tint.G, Tint.B, (byte)(255 * CurOpacity)));
                        break;

                    case Ticker.Font.InGame_Tiny:
                        GenericBaseApplication.GameManager.InGameFontTiny.DrawString(new Vector2((int)Position.X - Width / 2 + padding + ImageWidth / 2, (int)Position.Y + Height / 2), Text, new Color(Tint.R, Tint.G, Tint.B, (byte)(255 * CurOpacity)));
                        break;
                }
            }
        }


        private static SpriteBatch mSpriteBatch = new SpriteBatch(GenericBaseApplication.GameManager.GraphicsDevice);
        private static List<Message> mMessages = new List<Message>();
        private static float mFadeTime = 1f;


        /// <summary>
        /// Displays a string and/or graphic on top of all other graphics
        /// </summary>
        /// <param name="offsetFromCenter">Offset in pixels to draw the message, relative to the screen's center and the message's center</param>
        /// <param name="font">Which font to use</param>
        /// <param name="text">The string to display</param>
        /// <param name="seconds">Duration to display the message</param>
        /// <param name="fade">Whether or not to fade in and fade out the message</param>
        /// <param name="image">The image to display</param>
        /// <param name="velocity">Velocity (in pixels/second) to scroll the text</param>
        public static void Display(string text, Texture2D image, Vector2 imageSize, Vector2 offsetFromCenter, Vector2 velocity, Ticker.Font font, Color color, float opacity, float seconds, bool fade)
        {
            Message mes = new Message();
            mes.Text = text;
            mes.Image = image;
            mes.Position = new Vector2(GenericBaseApplication.GameManager.ScreenWidth / 2f + offsetFromCenter.X, GenericBaseApplication.GameManager.ScreenHeight / 2f + offsetFromCenter.Y);
            mes.Velocity = velocity;
            mes.ImageWidth = (int)imageSize.X;
            mes.ImageHeight = (int)imageSize.Y;
            mes.Font = font;
            mes.Tint = color;
            mes.Lifetime = seconds;
            mes.FinOpacity = opacity;
            mes.FadesIn = fade;
            mes.FadesOut = fade;
            if (fade)
                mes.CurOpacity = 0f;
            else
                mes.CurOpacity = opacity;

            // Find the string's dimensions
            Rectangle size = Rectangle.Empty;
            switch (font)
            {
                case Ticker.Font.Standard:
                    size = GenericBaseApplication.GameManager.StandardFont.MeasureString(text);
                    break;

                case Ticker.Font.Standard_Big:
                    size = GenericBaseApplication.GameManager.StandardFontBig.MeasureString(text);
                    break;

                case Ticker.Font.Space:
                    size = GenericBaseApplication.GameManager.SpaceFont.MeasureString(text);
                    break;

                case Ticker.Font.Space_Big:
                    size = GenericBaseApplication.GameManager.SpaceFontBig.MeasureString(text);
                    break;

                case Ticker.Font.InGame_Tiny:
                    size = GenericBaseApplication.GameManager.InGameFontTiny.MeasureString(text);
                    break;
            }
            mes.Width = size.Width;
            mes.Height = size.Height;

            mMessages.Add(mes);
        }

        
        /// <summary>
        /// Call this during the main game's update cycle
        /// </summary>
        /// <param name="gametime"></param>
        public static void Update()
        {
            float dT = GenericBaseApplication.GameManager.ElapsedSeconds;
            List<Message> deathRow = new List<Message>();
            foreach (Message message in mMessages)
            {
                // Update clock
                message.Lifetime -= dT;

                // Alter position
                message.Position += message.Velocity * dT;

                // Alter opacity
                if (message.FadesIn && message.CurOpacity < message.FinOpacity)
                {
                    message.CurOpacity += dT * mFadeTime;
                    if (message.CurOpacity >= message.FinOpacity)
                    {
                        message.FadesIn = false;
                        message.CurOpacity = message.FinOpacity;
                    }
                }
                if (message.FadesOut && message.Lifetime < 0)
                {
                    message.CurOpacity -= dT * mFadeTime;
                }
                if (message.CurOpacity < 0)
                    message.CurOpacity = 0f;

                // Check for expired messages
                if (message.Lifetime < 0 && !message.FadesOut ||
                    message.Lifetime < 0 - mFadeTime && message.FadesOut)
                    deathRow.Add(message);
            }

            // Remove expired messages
            foreach (Message corpse in deathRow)
                mMessages.Remove(corpse);
        }


        /// <summary>
        /// Draws all registered text on a new spritebatch
        /// </summary>
        public static void Draw()
        {
            // Minimize creation of spritebatches
            if (mMessages.Count == 0)
                return;

            mSpriteBatch.Begin(SpriteBlendMode.AlphaBlend, SpriteSortMode.Texture, SaveStateMode.None);

            foreach (Message message in mMessages)
                message.Draw(mSpriteBatch);

            mSpriteBatch.End();
        }
    }
}