/**
* Grabs weather data from Google.com's weather API and return a nicely formatted array
*
* @author Ashwin Surajbali
* @package Redink Design
* @version 0.9.2
*
* @example
* $w = new googleWeather();
* $w->enable_cache = 1;
* $w->cache_path = '/var/www/mysite.com/cache';
* $ar_data = $w->get_weather_data(10027);
* print_r($ar_data);
* echo $ar_data['forecast'][0]['day_of_week'];
*
* Requires PHP 5 or greater
*
*/

class googleWeather{

/**
* Search Value
*
* @var str
*/
public $search;

/**
* Disable or enable caching
*
* @var boolean
*/
public $enable_cache = 0;

/**
* Path to your cache directory
* eg. /www/website.com/cache
*
* @var string
*/
public $cache_path = '';

/**
* Cache expiration time in seconds
* Default: 3600 = 1 Hour
* If the cached file is older than 1 hour, new data is fetched
*
* @var int
*/
public $cache_time = 3600; // 1 hour

/**
* Full location of the cache file
*
* @var string
*/
private $cache_file;

/**
* Location of the google weather api
*
* @var string
*/
private $gweather_api_url = 'http://www.google.com/ig/api?hl=%s&weather=%s';

/**
* Storage var for data returned from curl request to the google api
*
* @var string
*/
private $raw_data;

/**
* Pull weather information for 'Zipcode' or 'City' passed in
* If enable_cache = true, data is cached and refreshed every hour
* Weather data is returned in an associative array
*
* @param int $zip
* @return array
*/
public function get_weather_data($search, $lang="en"){
$this->search = $search;

if ($this->search == 0 || strlen($this->search) < 5 || !is_numeric($this->search)){
$this->city = $this->search;
} else {
$this->zip = $this->search;
};

$this->cache_file = $this->cache_path . '/' . $this->search;

// build the url
$this->gweather_api_url = sprintf($this->gweather_api_url, $lang, urlencode($this->search));

if ($this->make_request()){

$xml = new SimpleXMLElement($this->raw_data);
$return_array = array();

$return_array['forecast_info']['city'] = $xml->weather->forecast_information->city['data'];
$return_array['forecast_info']['zip'] = $xml->weather->forecast_information->postal_code['data'];
$return_array['forecast_info']['date'] = $xml->weather->forecast_information->forecast_date['data'];
$return_array['forecast_info']['date_time'] = $xml->weather->forecast_information->current_date_time['data'];

$return_array['current_conditions']['condition'] = $xml->weather->current_conditions->condition['data'];
$return_array['current_conditions']['temp_f'] = $xml->weather->current_conditions->temp_f['data'];
$return_array['current_conditions']['temp_c'] = $xml->weather->current_conditions->temp_c['data'];
$return_array['current_conditions']['humidity'] = $xml->weather->current_conditions->humidity['data'];
$return_array['current_conditions']['icon'] = 'http://www.google.com' . $xml->weather->current_conditions->icon['data'];
$return_array['current_conditions']['wind'] = $xml->weather->current_conditions->wind_condition['data'];

for ($i = 0; $i < count($xml->weather->forecast_conditions); $i++){
$data = $xml->weather->forecast_conditions[$i];
$return_array['forecast'][$i]['day_of_week'] = $data->day_of_week['data'];
$return_array['forecast'][$i]['low'] = $data->low['data'];
$return_array['forecast'][$i]['high'] = $data->high['data'];
$return_array['forecast'][$i]['icon'] = 'http://img0.gmodules.com/' . $data->icon['data'];
$return_array['forecast'][$i]['condition'] = $data->condition['data'];
}

}

return $return_array;

}

private function load_from_cache(){
if ($this->enable_cache){
if (file_exists($this->cache_file)){
$file_time = filectime($this->cache_file);
$now = time();
$diff = ($now-$file_time);

if ($diff < = 3600){
return file_get_contents($this->cache_file);
}
}
}
}

private function write_to_cache($data){
if ($this->enable_cache) {
if (!file_exists($this->cache_path)){
// attempt to make the dir
mkdir($this->cache_path, 0777);
}
if (!file_put_contents($this->cache_file, $data)){
echo "
Could not save data to cache. Please make sure your cache directory exists and is writable.
";
}
};
}

private function make_request(){
/*
$ch = curl_init();
curl_setopt ($ch, CURLOPT_RETURNTRANSFER, 1);
curl_setopt ($ch, CURLOPT_URL, $this->gweather_api_url);
curl_setopt($ch, CURLOPT_USERAGENT, $_SERVER['HTTP_USER_AGENT']);
curl_setopt ($ch, CURLOPT_TIMEOUT, 60);
curl_setopt($ch, CURLOPT_FOLLOWLOCATION, true);
$this->raw_data = curl_exec ($ch);
curl_close ($ch);
*/

$data = $this->load_from_cache();
if (!empty($data)) {
$this->raw_data=$data;
return true;
} else {
$this->raw_data = file_get_contents($this->gweather_api_url);
if (empty($this->raw_data)){
return false;
} else {
$this->raw_data=str_replace('< ?xml version="1.0"?>', '< ?xml version="1.0" encoding="ISO-8859-1"?>', $this->raw_data);
$this->write_to_cache($this->raw_data);
return true;
};
};

}

}