<?php
// $Id: charts_graphs.module,v 1.1 2009-03-04 11:08:45 inadarei Exp $

/**
* @File Drupal module file
*/


charts_graphs_noncache_init();

/**
* Can not use hook_init since that one is cached and
* this function may never be cached.
*/
function charts_graphs_noncache_init() {
  require_once( dirname(__FILE__) . '/charts_graphs.class.inc' );
  $api_providers = array();
  
  $hook = 'chartgraph_provider';
  foreach (module_implements($hook) as $module) {
    $function = $module .'_'. $hook;
    $result = call_user_func_array($function, array());
    if (!empty($result) && is_object($result)) {
      $result->modulename = $module;
      chart_graphs_apis($result); //save it as a provider;
    }
  }
    
}
/**
* Return the list of Graphing implementations available (if no parameter
* is passed) or add a new implementation to the static list.
**/
function chart_graphs_apis ( $api_class=null ) {
  static $apis;
  
  if (empty($apis)) $api = array();
  
  if (!empty($api_class)) {
    $apis[$api_class->name] = $api_class;    
    unset( $apis[$api_class->name]->name );
  } else {
    return $apis;
  }
}

/**
* Factory method that allows instantiating of a 
* charting implementation class by implementation
* name.
*/
function chart_graphs_get_graph($name) {
  $apis = chart_graphs_apis();
  $api = $apis[$name];
    
  if (!empty($api) && is_object($api)) {
    require_once($api->path);  
    $canvas = new $api->clazz($api->modulename);    
    return $canvas;    
  }
  else {
    return FALSE;
  }  

}


/** Sequential generator of IDs, guaranteeing unique value per HTTP request **/
function chart_graphs_chart_id_generator() {
  static $id;
  
  if (empty($id)) {$id = 0;}
  $id++;
  
  return $id;
}

/** Random, unique string generator, to be used for cache_id in async data retrieval **/
function chart_graphs_random_hash() {

  list($usec, $sec) = explode(' ', microtime());
  $seed =  (float) $sec + ((float) $usec * 100000);
  mt_srand($seed);
  
  $randval1 = (string)mt_rand();
  $randval2 = (string)mt_rand();
  $randval3 = (string)mt_rand();  
  
  $rand = $randval1 . $randval2 . $randval3;
  $randhash = md5($rand);
  
  return "chgr_" . (string)$randhash;

}

/** For debugging only

function charts_graphs_menu() {
  $items = array();

  $items['charts/test'] = array(
    'title' => 'Charts Test',
    'page callback' => 'charts_graphs_test',
    'access arguments' => array('access content'),
    'type' => MENU_CALLBACK,
  );

  return $items;
}

function charts_graphs_test() {
  $canvas = chart_graphs_get_graph('open-flash');
    
  $canvas->title = "Open Flash Chart";
  $canvas->type = "bar_glass"; //"bar_3d";
  $canvas->y_legend = "Y Legend";
  $canvas->colour = '#D54C78';
  $canvas->series = array(
    'Some Value' => array(9,6,7,9,5,7,6,9,7),
    'Page Views' => array(6,7,9,5,7,6,9,7,3),
  );
  
  $out = $canvas->get_chart();
  return $out;
}**/