package be.nikiroo.fanfix_swing.gui.book;

import java.awt.Color;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.Polygon;
import java.awt.Rectangle;
import java.awt.image.BufferedImage;
import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.net.MalformedURLException;

import javax.imageio.ImageIO;

import be.nikiroo.fanfix.Instance;
import be.nikiroo.fanfix.data.MetaData;
import be.nikiroo.fanfix.library.BasicLibrary;
import be.nikiroo.fanfix.reader.ui.GuiReaderBookInfo;
import be.nikiroo.utils.Image;
import be.nikiroo.utils.ui.ImageUtilsAwt;
import be.nikiroo.utils.ui.UIUtils;

/**
 * This class can create a cover icon ready to use for the graphical
 * application.
 * 
 * @author niki
 */
class BookCoverImager {
	// TODO: export some of the configuration options?
	static final int COVER_WIDTH = 100;
	static final int COVER_HEIGHT = 150;
	static final int SPINE_WIDTH = 5;
	static final int SPINE_HEIGHT = 5;
	static final int HOFFSET = 20;
	static final Color SPINE_COLOR_BOTTOM = new Color(180, 180, 180);
	static final Color SPINE_COLOR_RIGHT = new Color(100, 100, 100);
	static final Color BORDER = Color.black;

	public static final Color UNCACHED_ICON_COLOR = new Color(0, 80, 220);

	public static final int TEXT_HEIGHT = 50;
	public static final int TEXT_WIDTH = COVER_WIDTH + 40;

	//

	static public Color getBackground(boolean enabled, boolean selected, boolean hovered) {
		Color color = new Color(255, 255, 255, 0);
		if (!enabled) {
		} else if (selected && !hovered) {
			color = new Color(80, 80, 100, 40);
		} else if (!selected && hovered) {
			color = new Color(230, 230, 255, 100);
		} else if (selected && hovered) {
			color = new Color(200, 200, 255, 100);
		}

		return color;
	}

	/**
	 * Draw a partially transparent overlay if needed depending upon the selection
	 * and mouse-hover states on top of the normal component, as well as a possible
	 * "cached" icon if the item is cached.
	 * 
	 * @param g        the {@link Graphics} to paint onto
	 * @param enabled  draw an enabled overlay
	 * @param selected draw a selected overlay
	 * @param hovered  draw a hovered overlay
	 * @param cached   draw a non-cached overlay if needed
	 */
	static public void paintOverlay(Graphics g, boolean enabled, boolean selected, boolean hovered, boolean cached) {
		Rectangle clip = g.getClipBounds();
		if (clip.getWidth() <= 0 || clip.getHeight() <= 0) {
			return;
		}

		int h = COVER_HEIGHT;
		int w = COVER_WIDTH;
		int xOffset = (TEXT_WIDTH - COVER_WIDTH) - 1;
		int yOffset = HOFFSET;

		if (BORDER != null) {
			if (BORDER != null) {
				g.setColor(BORDER);
				g.drawRect(xOffset, yOffset, COVER_WIDTH, COVER_HEIGHT);
			}

			xOffset++;
			yOffset++;
		}

		int[] xs = new int[] { xOffset, xOffset + SPINE_WIDTH, xOffset + w + SPINE_WIDTH, xOffset + w };
		int[] ys = new int[] { yOffset + h, yOffset + h + SPINE_HEIGHT, yOffset + h + SPINE_HEIGHT, yOffset + h };
		g.setColor(SPINE_COLOR_BOTTOM);
		g.fillPolygon(new Polygon(xs, ys, xs.length));
		xs = new int[] { xOffset + w, xOffset + w + SPINE_WIDTH, xOffset + w + SPINE_WIDTH, xOffset + w };
		ys = new int[] { yOffset, yOffset + SPINE_HEIGHT, yOffset + h + SPINE_HEIGHT, yOffset + h };
		g.setColor(SPINE_COLOR_RIGHT);
		g.fillPolygon(new Polygon(xs, ys, xs.length));

		Color color = getBackground(enabled, selected, hovered);

		g.setColor(color);
		g.fillRect(clip.x, clip.y, clip.width, clip.height);

		if (!cached) {
			UIUtils.drawEllipse3D(g, UNCACHED_ICON_COLOR, COVER_WIDTH + HOFFSET + 30, 10, 20, 20);
		}
	}

	/**
	 * Generate a cover icon based upon the given {@link MetaData}.
	 * 
	 * @param lib  the library the meta comes from
	 * @param meta the {@link MetaData}
	 * 
	 * @return the image
	 */
	static public java.awt.Image generateCoverImage(BasicLibrary lib, MetaData meta) {
		return generateCoverImage(lib, BookInfo.fromMeta(lib, meta));
	}

	/**
	 * The width of a cover image.
	 * 
	 * @return the width
	 */
	static public int getCoverWidth() {
		return SPINE_WIDTH + COVER_WIDTH;
	}

	/**
	 * The height of a cover image.
	 * 
	 * @return the height
	 */
	static public int getCoverHeight() {
		return COVER_HEIGHT + HOFFSET;
	}

	/**
	 * Generate a cover icon based upon the given {@link GuiReaderBookInfo}.
	 * 
	 * @param lib  the library the meta comes from (can be NULL)
	 * @param info the {@link GuiReaderBookInfo}
	 * 
	 * @return the image
	 */
	static public java.awt.Image generateCoverImage(BasicLibrary lib, BookInfo info) {
		BufferedImage resizedImage = null;
		String id = getIconId(info);

		InputStream in = Instance.getInstance().getCache().getFromCache(id);
		if (in != null) {
			try {
				resizedImage = ImageUtilsAwt.fromImage(new Image(in));
				in.close();
				in = null;
			} catch (IOException e) {
				Instance.getInstance().getTraceHandler().error(e);
			}
		}

		if (resizedImage == null) {
			try {
				Image cover = null;
				if (info != null) {
					cover = info.getBaseImage(lib);
				}

				resizedImage = new BufferedImage(getCoverWidth(), getCoverHeight(), BufferedImage.TYPE_4BYTE_ABGR);

				Graphics2D g = resizedImage.createGraphics();
				try {
					g.setColor(Color.white);
					g.fillRect(0, HOFFSET, COVER_WIDTH, COVER_HEIGHT);

					if (cover != null) {
						BufferedImage coverb = ImageUtilsAwt.fromImage(cover);
						g.drawImage(coverb, 0, HOFFSET, COVER_WIDTH, COVER_HEIGHT, null);
					} else {
						g.setColor(Color.black);
						g.drawLine(0, HOFFSET, COVER_WIDTH, HOFFSET + COVER_HEIGHT);
						g.drawLine(COVER_WIDTH, HOFFSET, 0, HOFFSET + COVER_HEIGHT);
					}
				} finally {
					g.dispose();
				}

				// Only save image with a cover, not the X thing
				if (id != null && cover != null) {
					ByteArrayOutputStream out = new ByteArrayOutputStream();
					ImageIO.write(resizedImage, "png", out);
					byte[] imageBytes = out.toByteArray();
					in = new ByteArrayInputStream(imageBytes);
					Instance.getInstance().getCache().addToCache(in, id);
					in.close();
					in = null;
				}
			} catch (MalformedURLException e) {
				Instance.getInstance().getTraceHandler().error(e);
			} catch (IOException e) {
				Instance.getInstance().getTraceHandler().error(e);
			}
		}

		return resizedImage;
	}

	/**
	 * Manually clear the icon set for this item.
	 * 
	 * @param info the info about the story or source/type or author
	 */
	static public void clearIcon(BookInfo info) {
		String id = getIconId(info);
		Instance.getInstance().getCache().removeFromCache(id);
	}

	/**
	 * Get a unique ID from this {@link GuiReaderBookInfo} (note that it can be a
	 * story, a fake item for a source/type or a fake item for an author).
	 * 
	 * @param info the info or NULL for a generic (non unique!) ID
	 * @return the unique ID
	 */
	static private String getIconId(BookInfo info) {
		return (info == null ? "" : info.getId() + ".") + "book-thumb_" + SPINE_WIDTH + "x" + COVER_WIDTH + "+"
				+ SPINE_HEIGHT + "+" + COVER_HEIGHT + "@" + HOFFSET;
	}
}