<?php

$USER = 'llucax';
$PERIOD = '7day'; // 7day, 3moth, 6month, 12month, overall
// black, gray, blue, red, orange, turquoise, trans, white
// or array(R, G, B) for an arbitrary color
$STYLE = array(246,146,30);
$N_ARTISTS = 10;
$COLUMNS = 1; // 1 or 2
$API_KEY = "db109383394640f2b5e174b4514f0014";
$GRAY_VALUE = 239;
$MARGIN_SIDE = 4; // Side margin (in px)
$MARGIN_TOP = 4; // Between the first logo and top
$SEPERATION = 5; // Separation between logos
$LOGOS_DIR = 'logos';

/**
 * @param string Name of the artist
 * @return Artist Infos of the artist
 */
function get_artist_image($name)
{
	global $LOGOS_DIR;
	foreach (glob($LOGOS_DIR . '/' . $name . '.*') as $file) {
		$info = pathinfo($file);
		$ext = strtolower($info['extension']);
		if ($ext == 'gif')
			return imagecreatefromgif($file);
		if ($ext == 'jpeg' || $ext == 'jpg')
			return imagecreatefromjpeg($file);
		if ($ext == 'png')
			return imagecreatefrompng($file);
	}
	return null;
}

/**
 * Invert color from an image ressource.
 *
 * @param ressource $image Image
 * "param string $color ID of a filter
 */
function img_apply_filter($image, $color)
{
	if ($color == 'black')
		img_add_invert_filter($image);
	elseif ($color == 'gray')
		img_add_gray_filter($image);
	elseif ($color == 'blue')
		img_add_color_filter($image, array(40,79,148));
	elseif ($color == 'red')
		img_add_color_filter($image, array(214,17,2));
	elseif ($color == 'orange')
		img_add_color_filter($image, array(222,54,0));
	elseif ($color == 'turquoise')
		img_add_color_filter($image, array(69,168,196));
	elseif ($color == 'trans')
		img_add_trans_filter($image);
	elseif ($color == 'white')
		return;
	elseif (is_array($color))
		img_add_color_filter($image, $color);
	else
		throw new Exception("Unknown filter.");
}


/**
 * Invert color from an image ressource.
 *
 * @param ressource $image Image
 */
function img_add_invert_filter($image)
{
	$width = imagesx($image);
	$height = imagesy($image);

	for ($x = 0; $x < $width; $x++) {
		for ($y = 0; $y < $height; $y++) {
			$oldCol = img_get_color_array($image,$x,$y);
			$newColor = img_get_invert_color($oldCol);
			imagesetpixel($image, $x, $y,
				img_get_col_ref($image,$newColor));
		}
	}
}

/**
 * Make the image darker and make the background transparent.
 *
 * @param ressource $image Image
 */
function img_add_trans_filter($image) {
	global $GRAY_VALUE;
	$height = imagesy($image);
	// Set gray as the transparent color
	$ref = imagecolorresolve($image, $GRAY_VALUE, $GRAY_VALUE, $GRAY_VALUE);
	imagecolortransparent($image, $ref);

	for ($x = 0; $x < $width; $x++) {
		for ($y = 0; $y < $height; $y++) {
			$oldCol = img_get_color_array($image, $x, $y);
			$newColor = img_get_darker_color($oldCol, $GRAY_VALUE);
			imagesetpixel($image, $x, $y,
				img_get_col_ref($image,$newColor,$ref));
		}
	}
}

/**
 * Make the image darker.
 * - White pixel become darker.
 * - Black pixel stay the same.
 *
 * @param ressource $image Image
 */
function img_add_gray_filter($image)
{
	global $GRAY_VALUE;

	$width = imagesx($image);
	$height = imagesy($image);

	for ($x = 0; $x < $width; $x++) {
		for ($y = 0; $y < $height; $y++) {
			$oldCol = img_get_color_array($image, $x, $y);
			$newColor = img_get_darker_color($oldCol, $GRAY_VALUE);
			imagesetpixel($image, $x, $y,
				img_get_Col_Ref($image,$newColor));
		}
	}
}

/**
 * Replace the black color and dark tone to the given color.
 *
 * @param ressource $image Image
 * @param array $color Color that will replace black
 */
function img_add_color_filter($image, array $color)
{
	global $GRAY_VALUE;

	$width = imagesx($image);
	$height = imagesy($image);

	$ref = imagecolorresolve($image, $GRAY_VALUE, $GRAY_VALUE, $GRAY_VALUE);
	imagecolortransparent($image,$ref);

	for ($x = 0; $x < $width; $x++) {
		for ($y = 0; $y < $height; $y++) {
			$oldCol = img_get_color_array($image, $x, $y);
			$newColor = img_change_dark_to_spec_color(
				img_get_darker_color($oldCol, $GRAY_VALUE),$color);
			imagesetpixel($image, $x, $y,
				img_get_col_ref($image, $newColor, $ref));
		}
	}
}

////// Color basic util. //////

/**
 * Simple shortcut to get a color ref for the current image.
 *
 * @param ressource $image Image
 * @param array $newColor RGB color array of the color added
 * @param int $transRef If set should  reference the transparent color id
 * @return Return the ref id to the new color (can only be use for the given image)
 */
function img_get_col_ref($image, array $newColor, $transRef=NULL)
{
	global $GRAY_VALUE;

	$ref = imagecolorresolve($image, $newColor[0], $newColor[1],
		$newColor[2]);
	if ($transRef && (array_sum($newColor) >= ($GRAY_VALUE - 15) * 3))
		$ref = $transRef; // imagecolortransparent($image,$ref);
	return $ref;
}

/**
 * @param ressource $image Image
 * @param int $x X position
 * @param int $y Y position
 * @return Get the RGB array for a given position
 */
function img_get_color_array($image, $x, $y)
{
	$pos = imagecolorat($image, $x, $y);
	$f = imagecolorsforindex($image, $pos);
	$col = NULL;

	if (count($f) == 3) {
		$col = array($f['red'], $f['green'], $f['blue']);
	}
	else {
		$gst = $f['red'] * 0.15 + $f['green'] * 0.5 + $f['blue'] * 0.35;
		$col = array($gst, $gst, $gst);
	}

	return $col;
}

////// Color modifications pattern //////

/**
 * @param array $color RGB color
 * @return the RGB opposite
 */
function img_get_invert_color(array $color)
{
	return array(255 - $color[0], 255 - $color[1], 255 - $color[2]);
}

/**
 * @param array $color RGB color
 * @param int $gray Gray Level (0-255) Lower is darker
 * @return a RGB color darker than the original
 */
function img_get_Darker_color(array $color, $gray)
{
	$color[0] -= $color[0] / 255 * (255 - $gray);

	// Base on the assumption the color are grayscale
	$color[2] = $color[1] = $color[0];

	return $color;
}

 /**
 * 
 */
function img_change_dark_to_spec_color(array $color, array $newColor)
{
	global $GRAY_VALUE;

	$sum = array_sum($color);

	if ($sum < ($GRAY_VALUE - 15) * 3) {
		$color[0] += $newColor[0] * (255 - $color[0]) / 255;
		$color[1] += $newColor[1] * (255 - $color[1]) / 255;
		$color[2] += $newColor[2] * (255 - $color[2]) / 255;
	}
	return $color;
}

/**
 * Output the image with the logos of each artist
 */
function show_one_col($artists, $artists_no, $color, $width)
{
	global $MARGIN_TOP, $MARGIN_SIDE, $SEPERATION;

	$totalHeight=0;
	$listImageRessources = array();

	foreach ($artists as $name) {
		if (count($listImageRessources) == $artists_no)
			break;

		$image = get_artist_image($name);

		if ($image !== null) {
			$totalHeight += imagesy($image) + $SEPERATION;
			array_push($listImageRessources, $image);
		}
	}
	$totalHeight += $MARGIN_TOP;

	$container = imagecreatetruecolor($width, $totalHeight);

	// Some colors needed
	$colWhite = imagecolorallocate($container, 255, 255, 255);

	// Background color
	imagefilledrectangle($container, 0, 0, $width, $totalHeight, $colWhite);

	$expectWidth = $width - (2 * $MARGIN_SIDE);
	$currentHeight = $MARGIN_TOP;
	foreach ($listImageRessources as $image) {
		$widthImg = imagesx($image);
		imagecopymerge($container, $image,
			$MARGIN_SIDE + ($widthImg < $expectWidth ?
					($expectWidth - $widthImg) * 0.5 : 0),
			$currentHeight, 0, 0, imagesx($image), imagesy($image),
			100);
		$currentHeight += imagesy($image) + $SEPERATION;
	}

	img_apply_filter($container, $color);

	imagepng($container);
}

/**
 * Output the image with the logos of each artist
 */
function show_two_col($artists, $artists_no, $color, $width)
{
	global $MARGIN_TOP, $MARGIN_SIDE, $SEPERATION;

	if (count($artists) == 0)
		throw new Exception("Missing some informations (artists).");

	$totalHeight = array($MARGIN_TOP, $MARGIN_TOP);
	$listImageRessources = array(array(), array());

	$forcedWidth = ($width / 2) - ($SEPERATION / 2);

	foreach ($artists as $name) {
		if (count($listImageRessources[0]) +
				count($listImageRessources[1]) == $artists_no)
			break;

		$image = get_artist_image($name);

		if ($image !== null) {
			$i = 0;
			if ($totalHeight[1] < $totalHeight[0])
				$i = 1;

			$x = imagesx($image);
			$y = imagesy($image);
			$newHeight = floor(($y * $forcedWidth) / $x);

			$totalHeight[$i] += $newHeight + $SEPERATION;
			array_push($listImageRessources[$i], $image);
		}
	}

	$container = imagecreatetruecolor($width, max($totalHeight));

	// Some colors needed
	$colWhite = imagecolorallocate($container, 255, 255, 255);

	// Background color
	imagefilledrectangle($container, 0, 0, $width, max($totalHeight), $colWhite);

	$currentHeight = array($MARGIN_TOP, $MARGIN_TOP);
	for ($l = 0; $l < count($listImageRessources); $l++) {
		$list = $listImageRessources[$l];

		foreach ($list as $image) {
			$x = imagesx($image);
			$y = imagesy($image);

			$newHeight = floor(($y * $forcedWidth) / $x);

			$resized = imagecreatetruecolor($forcedWidth, $newHeight);				
			imagecopyresampled($resized, $image, 0, 0, 0, 0,
				$forcedWidth, $newHeight, $x, $y);

			imagecopymerge($container, $resized,
				($forcedWidth + $SEPERATION) * $l,
				$currentHeight[$l], 0, 0,
				$forcedWidth, $newHeight, 100);

			$currentHeight[$l] += $newHeight + $SEPERATION;
		}
	}

	img_apply_filter($container, $color);

	imagepng($container);
}

/**
 * Optain the list of Top artists from a user
 * @param string $accountName Unique name
 * @param int $nbArtists Number of artists to list
 */
function get_list_top_artists($username, $type='overall', $nbArtists=0)
{
	global $API_KEY;
	if (strlen($username) == 0 || strlen($username) > 15)
		throw new Exception("Invalid username.");

	$content = file_get_contents("http://ws.audioscrobbler.com/2.0/" .
		"?method=user.gettopartists" .
		"&user=" . $username.
		"&period=" . $type.
		"&api_key=" . $API_KEY);
        $lines = explode("\n", $content);
	if (count($lines) == 0)
		throw new Exception("Feed is empty.");

	$artists = array();
	$noartist = 0;
	foreach ($lines as $line) {
		// Skip useless line
		if (strrpos($line, "<url>http://www.last.fm/music/") ===
				false)
			continue;

		// Extract the encode name from the url
		preg_match("(http://www.last.fm/music/([^<]+))", $line,
			$proper);
		array_push($artists, $proper[1]);
		$noartist++;

		if ($noartist == $nbArtists) // Stop when max
			break;
	}

	if (count($artists) == 0)
		throw new Exception("No Artist found. Invalid feed??");

	return $artists;
}

$artists = get_list_top_artists($USER, $PERIOD);

if (count($artists) > 0)
	if ($COLUMNS == 1)
		show_one_col($artists, $N_ARTISTS, $STYLE, 168);
	elseif ($COLUMNS == 2)
		show_two_col($artists, $N_ARTISTS, $STYLE, 300);
	else
		throw new Exception("Invalid number of columns.");
else
	throw new Exception("No artist found.");

?>