<?php
/*
 * Sparkline PHP Graphing Library
 * Copyright 2004 James Byers <jbyers@gmail.com>
 * http://sparkline.org
 *
 * Dual-licensed under the BSD (LICENSE-BSD.txt) and GPL (LICENSE-GPL.txt)
 * licenses.
 *
 * $Id: stock_chart2.php,v 1.1 2008-09-05 22:13:12 chris Exp $
 *
 * stock_chart2 adds min/max price bounds and an endpoint value label to
 * stock_chart
 *              
 * layout inspired by Mariano Belinky's SVG sparklines:
 * http://www.interactiva.com.ar/mariano/?pname=sparklines
 *
 */

//////////////////////////////////////////////////////////////////////////////
// verify parameters; bad form, but die to text error on failure
//
if (!isset($_GET['s']) ||
    !eregi('^[a-z\^]{1,5}$', $_GET['s'])) {
  die('bad ticker ' . $_GET['s']);
}

if (!isset($_GET['y']) ||
    !is_numeric($_GET['y']) ||
    $_GET['y'] > 5 ||
    $_GET['y'] < 0) {
  die('bad year ' . $_GET['y']);
}

//////////////////////////////////////////////////////////////////////////////
// load and process data from Yahoo! ichart csv source
//
$m  = date('n') - 1;
$d  = date('d');
$y2 = date('Y');
$y1 = $y2 - $_GET['y'];

// data sample:
//   0        1     2     3     4     5        6
//   Date,Open,High,Low,Close,Volume,Adj. Close*
//   5-Nov-04,29.21,29.36,29.03,29.31,95337696,29.31
//
$url = "http://ichart.finance.yahoo.com/table.csv?s=" . $_GET['s'] . "&a=$m&b=$d&c=$y1&d=$m&e=$d&f=$y2&g=d&ignore=.csv";
if (!$data = @file($url)) {
  die('error fetching stock data; verify ticker symbol');
}

//////////////////////////////////////////////////////////////////////////////
// build sparkline using standard flow:
//   construct, set, render, output
//
require_once('../lib/Sparkline_Line.php');

$sparkline = new Sparkline_Line();
$sparkline->SetDebugLevel(DEBUG_NONE);
//$sparkline->SetDebugLevel(DEBUG_ERROR | DEBUG_WARNING | DEBUG_STATS | DEBUG_CALLS, '../log.txt');

if (isset($_GET['b'])) {
  $sparkline->SetColorHtml('background', $_GET['b']);
  $sparkline->SetColorBackground('background');
}

$data = array_reverse($data);
$i = 0;
$min  = null;
$max  = null;
$last = null;
while (list(, $v) = each($data)) {
  $elements = explode(',', $v);
  $value    = @trim($elements[6]);

  if (ereg('^[0-9\.]+$', $value)) {

    $sparkline->SetData($i, $value);

    if (null == $max ||
        $value >= $max[1]) {
      $max = array($i, $value);
    }

    if (null == $min ||
        $value <= $min[1]) {
      $min = array($i, $value);
    }

    $last = array($i, $value);

    $i++;
  }
}

// set y-bound, min and max extent lines
//
$sparkline->SetYMin(0);
$sparkline->SetPadding(2); // setpadding is additive
$sparkline->SetPadding(imagefontheight(FONT_2), 
                       imagefontwidth(FONT_2) * strlen(" $last[1]"), 
                       0, //imagefontheight(FONT_2), 
                       0);
$sparkline->SetFeaturePoint($min[0],  $min[1],  'red',   5, $min[1],     TEXT_TOP,    FONT_2);
$sparkline->SetFeaturePoint($max[0],  $max[1],  'green', 5, $max[1],     TEXT_TOP,    FONT_2);
$sparkline->SetFeaturePoint($last[0], $last[1], 'blue',  5, " $last[1]", TEXT_RIGHT,  FONT_2);

if (isset($_GET['m']) &&
    $_GET['m'] == '0') {
  $sparkline->Render(200, 50);
} else {
  $sparkline->SetLineSize(3); // for renderresampled, linesize is on virtual image
  $sparkline->RenderResampled(200, 50);
}

// manually add a stock ticker label
//
$sparkline->DrawText(strtoupper($_GET['s']),
                     $sparkline->GetImageWidth() - (imagefontwidth(FONT_5) * strlen($_GET['s'])),
                     $sparkline->GetImageHeight() - imagefontheight(FONT_5),
                     'black',
                     FONT_5);

$sparkline->Output();

?>