/*
GanttProject is an opensource project management tool.
Copyright (C) 2011 GanttProject Team

This program is free software; you can redistribute it and/or
modify it under the terms of the GNU General Public License
as published by the Free Software Foundation; either version 3
of the License, or (at your option) any later version.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
 */
package net.sourceforge.ganttproject;

import java.awt.Color;
import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.RenderingHints;
import java.awt.image.BufferedImage;
import java.util.Iterator;
import java.util.List;

import biz.ganttproject.core.chart.render.TextLengthCalculatorImpl;

import net.sourceforge.ganttproject.font.Fonts;
import net.sourceforge.ganttproject.resource.HumanResource;
import net.sourceforge.ganttproject.resource.HumanResourceManager;
import net.sourceforge.ganttproject.task.ResourceAssignment;

class ResourceTreeImageGenerator {
  private HumanResourceManager myResourceManager;
  private final Color BORDER_COLOR_3D = new Color(0.807f, 0.807f, 0.807f);
  private final Color ODD_ROW_COLOR = new Color(0.933f, 0.933f, 0.933f);
  private final int myRowHeight;

  ResourceTreeImageGenerator(HumanResourceManager resourceManager) {
    myResourceManager = resourceManager;
    final BufferedImage testImage = new BufferedImage(10, 10, BufferedImage.TYPE_INT_RGB);
    final Graphics g = testImage.getGraphics();
    final int nameFontHeight = g.getFontMetrics().getHeight();
    final int nameLinePadding = 3;
    myRowHeight = nameFontHeight + 2 * nameLinePadding;
  }

  BufferedImage createImage() {
    Dimension d = calculateDimension();
    BufferedImage image = new BufferedImage(d.width, d.height, BufferedImage.TYPE_INT_RGB);
    Graphics g = image.getGraphics();
    g.setColor(Color.white);
    g.fillRect(0, 0, d.width, d.height);
    printResources(g, d.width);
    return image;
  }

  protected int getRowHeight() {
    return myRowHeight;
  }

  private Dimension calculateDimension() {
    int width = 0;
    int assignmentsCount = 0;
    final BufferedImage testImage = new BufferedImage(10, 10, BufferedImage.TYPE_INT_RGB);
    final Graphics2D g = (Graphics2D) testImage.getGraphics();
    final int tabSize = 5;
    final List<HumanResource> users = myResourceManager.getResources();
    for (Iterator<HumanResource> user = users.iterator(); user.hasNext();) {
      HumanResource hr = user.next();
      int nameWidth = TextLengthCalculatorImpl.getTextLength(g, hr.getName());
      if (nameWidth > width) {
        width = nameWidth;
      }
      ResourceAssignment[] assignments = hr.getAssignments();
      if (assignments != null) {
        for (int i = 0; i < assignments.length; i++) {
          if (isAssignmentVisible(assignments[i])) {
            int taskWidth = tabSize + TextLengthCalculatorImpl.getTextLength(g, assignments[i].getTask().getName());
            if (taskWidth > width) {
              width = taskWidth;
            }
            assignmentsCount++;
          }
        }
      }
    }
    width += 20;
    int height = (assignmentsCount + users.size()) * getRowHeight() + 90;
    return new Dimension(width, height);
  }

  private void printResources(Graphics g, int width) {
    ((Graphics2D) g).setRenderingHint(RenderingHints.KEY_TEXT_ANTIALIASING, RenderingHints.VALUE_TEXT_ANTIALIAS_ON);

    g.setColor(Color.black);
    g.setFont(Fonts.RESSOURCE_FONT);

    List<HumanResource> users = myResourceManager.getResources();

    int y = 67;

    final int nameLinePadding = 3;
    final int nameLineHeight = getRowHeight();
    boolean isOddRow = false;
    for (Iterator<HumanResource> user = users.iterator(); user.hasNext();) {
      HumanResource hr = user.next();
      {
        // paint resource name here
        String nameOfRes = hr.toString();

        if (isOddRow) {
          g.setColor(ODD_ROW_COLOR);
          g.fillRect(0, y, width, nameLineHeight);
        }
        g.setColor(Color.black);

        g.drawRect(0, y, width, nameLineHeight);

        g.drawString(nameOfRes, 5, y + nameLineHeight - nameLinePadding);
        g.setColor(BORDER_COLOR_3D);
        g.drawLine(1, y + nameLineHeight - 1, width - 1, y + nameLineHeight - 1);
        y += nameLineHeight;
        isOddRow = !isOddRow;
      }
      {
        // paint assigned task names
        ResourceAssignment[] assignments = hr.getAssignments();
        if (assignments != null) {
          for (int i = 0; i < assignments.length; i++) {
            if (isAssignmentVisible(assignments[i])) {
              if (isOddRow) {
                g.setColor(ODD_ROW_COLOR);
                g.fillRect(0, y, width, nameLineHeight);
              }
              g.setColor(Color.black);
              g.drawRect(0, y, width, nameLineHeight);
              g.drawString("  " + assignments[i].getTask().getName(), 5, y + nameLineHeight - nameLinePadding);
              g.setColor(BORDER_COLOR_3D);
              g.drawLine(1, y + nameLineHeight, width - 1, y + nameLineHeight - 1);
              y += nameLineHeight;
              isOddRow = !isOddRow;
            }
          }
        }
      }
    }
  }

  protected boolean isAssignmentVisible(ResourceAssignment assignment) {
    return true;
  }
}