<?php
	/* Libchart - PHP chart library
	 * Copyright (C) 2005-2007 Jean-Marc Trémeaux (jm.tremeaux at gmail.com)
	 *
	 * 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, see <http://www.gnu.org/licenses/>.
	 *
	 */

	defined('FULL_PATH') or die('restricted access!');

	/**
	 * Line chart.
	 *
	 * @author Jean-Marc Trémeaux (jm.tremeaux at gmail.com)
	 */
	class LibchartLineChart extends LibchartBarChart {
		/**
		 * Creates a new line chart.
		 * Line charts allow for XYDataSet and XYSeriesDataSet in order to plot several lines.
		 *
		 * @param integer width of the image
		 * @param integer height of the image
		 */
		public function __construct($width = 600, $height = 250) {
			parent::__construct($width, $height);

			$this->plot->setGraphPadding(new LibchartPadding(5, 30, 50, 50));
		}

		/**
		 * Computes the layout.
		 */
		protected function computeLayout() {
			if ($this->hasSeveralSerie) {
				$this->plot->setHasCaption(true);
			}
			$this->plot->computeLayout();
		}

		/**
		 * Print the axis.
		 */
		protected function printAxis() {
			$minValue = $this->axis->getLowerBoundary();
			$maxValue = $this->axis->getUpperBoundary();
			$stepValue = $this->axis->getTics();

			// Get graphical obects
			$img = $this->plot->getImg();
			$palette = $this->plot->getPalette();
			$text = $this->plot->getText();

			// Get the graph area
			$graphArea = $this->plot->getGraphArea();

			// Vertical axis
			for ($value = $minValue; $value <= $maxValue; $value += $stepValue) {
				$y = $graphArea->y2 - ($value - $minValue) * ($graphArea->y2 - $graphArea->y1) / ($this->axis->displayDelta);

				imagerectangle($img, $graphArea->x1 - 3, $y, $graphArea->x1 - 2, $y + 1, $palette->axisColor[0]->getColor($img));
				imagerectangle($img, $graphArea->x1 - 1, $y, $graphArea->x1, $y + 1, $palette->axisColor[1]->getColor($img));

				$text->printText($img, $graphArea->x1 - 5, $y, $this->plot->getTextColor(), $value, $text->fontCondensed, $text->HORIZONTAL_RIGHT_ALIGN | $text->VERTICAL_CENTER_ALIGN);
			}

			// Get first serie of a list
			$pointList = $this->getFirstSerieOfList();

			// Horizontal Axis
			$pointCount = count($pointList);
			reset($pointList);
			$columnWidth = ($graphArea->x2 - $graphArea->x1) / ($pointCount - 1);

			for ($i = 0; $i < $pointCount; $i++) {
				$x = $graphArea->x1 + $i * $columnWidth;

				imagerectangle($img, $x - 1, $graphArea->y2 + 2, $x, $graphArea->y2 + 3, $palette->axisColor[0]->getColor($img));
				imagerectangle($img, $x - 1, $graphArea->y2, $x, $graphArea->y2 + 1, $palette->axisColor[1]->getColor($img));

				$point = current($pointList);
				next($pointList);

				$label = $point->getX();

				$text->printDiagonal($img, $x - 5, $graphArea->y2 + 10, $this->plot->getTextColor(), $label);
			}
		}

		/**
		 * Print the lines.
		 */
		protected function printLine() {
			$minValue = $this->axis->getLowerBoundary();
			$maxValue = $this->axis->getUpperBoundary();

			// Get the data as a list of series for consistency
			$serieList = $this->getDataAsSerieList();

			// Get graphical obects
			$img = $this->plot->getImg();
			$palette = $this->plot->getPalette();
			$text = $this->plot->getText();
			$primitive = $this->plot->getPrimitive();

			// Get the graph area
			$graphArea = $this->plot->getGraphArea();

			$lineColorSet = $palette->lineColorSet;
			$lineColorSet->reset();
			for ($j = 0; $j < count($serieList); $j++) {
				$serie = $serieList[$j];
				$pointList = $serie->getPointList();
				$pointCount = count($pointList);
				reset($pointList);

				$columnWidth = ($graphArea->x2 - $graphArea->x1) / ($pointCount - 1);

				$lineColor = $lineColorSet->currentColor();
				$lineColorShadow = $lineColorSet->currentShadowColor();
				$lineColorSet->next();
				$x1 = null;
				$y1 = null;
				for ($i = 0; $i < $pointCount; $i++) {
					$x2 = $graphArea->x1 + $i * $columnWidth;

					$point = current($pointList);
					next($pointList);

					$value = $point->getY();

					$y2 = $graphArea->y2 - ($value - $minValue) * ($graphArea->y2 - $graphArea->y1) / ($this->axis->displayDelta);

					// Draw line
					if ($x1) {
						$primitive->line($x1, $y1, $x2, $y2, $lineColor, 4);
						$primitive->line($x1, $y1 - 1, $x2, $y2 - 1, $lineColorShadow, 2);
					}

					$x1 = $x2;
					$y1 = $y2;
				}
			}
		}

		/**
		 * Renders the caption.
		 */
		protected function printCaption() {
			// Get the list of labels
			$labelList = $this->dataSet->getTitleList();

			// Create the caption
			$caption = new LibchartCaption();
			$caption->setPlot($this->plot);
			$caption->setLabelList($labelList);

			$palette = $this->plot->getPalette();
			$lineColorSet = $palette->lineColorSet;
			$caption->setColorSet($lineColorSet);

			// Render the caption
			$caption->render();
		}

		/**
		 * Render the chart image.
		 *
		 * @param string name of the file to render the image to (optional)
		 */
		public function render($fileName = null) {
			// Check the data model
			$this->checkDataModel();

			$this->bound->computeBound($this->dataSet);
			$this->computeAxis();
			$this->computeLayout();
			$this->createImage();
			$this->plot->printLogo();
			$this->plot->printTitle();
			if (!$this->isEmptyDataSet(2)) {
				$this->printAxis();
				$this->printLine();
				if ($this->hasSeveralSerie) {
					$this->printCaption();
				}
			}

			$this->plot->render($fileName);
		}
	}