<?php
// $Id: designkit.module,v 1.1.2.3 2010-01-04 17:18:06 yhahn Exp $

/**
 * Implementation of hook_theme().
 */
function designkit_theme() {
  return array(
    'designkit_image' => array(),
    'designkit_colorpicker' => array(),
    'designkit' => array(
      'template' => 'designkit',
      'arguments' => array('color' => array(), 'image' => array()),
    ),
  );
}

/**
 * Turn design choices into theme variables.
 */
function designkit_preprocess_page(&$vars) {
  $info = designkit_get_info();
  $color = !empty($info['designkit']['color']) ? variable_get('designkit_color', $info['designkit']['color']) : array();
  $image = !empty($info['designkit']['image']) ? variable_get('designkit_image', array()) : array();

  // Process images array into an array of filepaths & add processed
  // version to page template.
  foreach ($image as $name => $fid) {
    $file = db_fetch_object(db_query('SELECT * FROM {files} f WHERE f.fid = %d', $fid));
    if ($file && $file->filepath && file_exists($file->filepath)) {
      $image[$name] = $file->filepath;
      $vars[$name] = theme('designkit_image', $name, $file->filepath);
    }
    else {
      unset($image[$name]);
    }
  }

  // Generate CSS styles.
  if ($image || array_filter($color, 'designkit_valid_color')) {
    // Add in designkit styles.
    $vars['body_classes'] .= " designkit";
    // Add styles to closure -- safest way to affect the page.
    $vars['closure'] .= theme('designkit', $color, $image);
  }
}

/**
 * Implementation of hook_imagecache_default_presets().
 */
function designkit_imagecache_default_presets() {
  $presets = array();

  // Generate imagecache presets per image entry in theme info.
  $info = designkit_get_info();
  if (!empty($info['designkit']['image'])) {
    foreach ($info['designkit']['image'] as $name => $image_info) {
      if (isset($image_info['imagecache'])) {
        list($action, $dimensions) = explode(':', $image_info['imagecache']);
        list($width, $height) = explode('x', $dimensions);
        $valid_actions = imagecache_action_definitions();
        if (isset($valid_actions[$action]) && is_numeric($width) && is_numeric($height)) {
          $presets["designkit-image-{$name}"] = array (
            'presetname' => "designkit-image-{$name}",
            'actions' => array (
              0 => array (
                'weight' => '0',
                'module' => 'imagecache',
                'action' => $action,
                'data' => array (
                  // @TODO: decide what to do with this hardcoded param.
                  'fit' => 'inside',
                  'width' => $width,
                  'height' => $height,
                ),
              ),
            ),
          );
        }
      }
    }
  }

  return $presets;
}

/**
 * Determine whether a given color string is valid.
 * Must be in the form of #ffffff (6 digit hex with preceding #) or
 * #fff (3 digit hex with preceding #).
 */
function designkit_valid_color($color) {
  $matches = array();
  preg_match('/(#[0-9a-f]{6}|#[0-9a-f]{3})/i', $color, $matches);
  if ($matches && (strlen($color) === 7 || strlen($color) === 3)) {
    return TRUE;
  }
  return FALSE;
}

/**
 * Retrieve designkit info for the site's default theme.
 */
function designkit_get_info($reset = FALSE) {
  static $info;
  if (!isset($info) || $reset) {
    global $theme_key, $theme_info;
    if (isset($theme_info, $theme_key) && $theme_key == variable_get('theme_default', 'garland')) {
      $info = $theme_info->info;
    }
    else {
      $default = variable_get('theme_default', 'garland');
      $result = db_query("SELECT name,type,info FROM {system} WHERE type = 'theme' AND name = '%s'", $default);
      while ($row = db_fetch_object($result)) {
        $info = unserialize($row->info);
      }
    }
  }
  return isset($info) ? $info : FALSE;
}

/**
 * Apply a shift color to a source color by a certain opacity value.
 *
 *  @param $source
 *    An RGB hex string. The source color to which a shift
 *    should be applied.
 *  @param $shift
 *    An RGB hex string. The shift color which defines the
 *    color that the source should shift towards.
 *  @param $opacity
 *    A float between 0 and 1 that determines what opacity to use
 *    for the blending shift color.
 *  @return
 *    An RGB hex string.
 */
function designkit_colorshift($source, $shift, $opacity = .5) {
  if (designkit_valid_color($source) && designkit_valid_color($shift)) {
    $source  = _color_unpack($source, TRUE);
    $shift   = _color_unpack($shift, TRUE);
    $shifted = array();
    foreach (array_keys($source) as $key) {
      // shifted = original color + (difference * opacity).
      $shifted[$key] = $source[$key] + (($shift[$key] - $source[$key]) * $opacity);
    }
    return _color_pack($shifted, TRUE);
  }
  return $source;
}

/**
 * Retrieve the HSL of a color, or the specified component.
 *
 *  @param $source
 *    An RGB hex string. The source color from which to retrieve HSL values.
 *  @param $key
 *    Optional string key (either 'h', 's' or 'l') for the HSL component
 *    to retrieve.
 *  @return
 *    Either an array of HSL values or the single component specified by $key.
 */
function designkit_colorhsl($source, $key = NULL) {
  if (designkit_valid_color($source)) {
    $source  = _color_unpack($source, TRUE);
    $hsl = _color_rgb2hsl($source);
    $keys = array('h' => 0, 's' => 1, 'l' => 2);
    if (isset($key, $keys[$key])) {
      return isset($hsl[$keys[$key]]) ? $hsl[$keys[$key]] : NULL;
    }
    return $hsl;
  }
  return NULL;
}

/**
 * Spaces integration.
 * Implementation of hook_form_alter() for spaces_features_form.
 */
function designkit_form_spaces_features_form_alter(&$form, &$form_state) {
  module_load_include('inc', 'designkit', 'designkit.admin');
  _designkit_form_alter($form, $form_state);
}

/**
 * Theme integration.
 * Implementation of hook_form_alter() for system_theme_settings.
 */
function designkit_form_system_theme_settings_alter(&$form, &$form_state) {
  module_load_include('inc', 'designkit', 'designkit.admin');
  _designkit_form_alter($form, $form_state);

  // weight buttons if not weighted already.
  $form['buttons']['#weight'] = !isset($form['buttons']['#weight']) ? 10 : $form['buttons']['#weight'];

  // yank logo if DesignKit will provide one with the same key.
  $form['logo']['#access'] = !isset($form['designkit_image']['logo']);

  // system_theme_settings form requires an additional submit handler.
  $form['#submit'][] = '_designkit_system_theme_settings_submit';
}

/**
 * Preprocessor for theme('designkit').
 */
function template_preprocess_designkit(&$vars) {
  // Map each color to a corresponding variable name.
  foreach ($vars['color'] as $key => $color) {
    $vars[$key] = $color;
  }
  // Map each image to a corresponding variable name.
  // Provide a _raw version for non-imagecache processed URLs.
  foreach ($vars['image'] as $key => $filepath) {
    $vars[$key] = imagecache_create_url("designkit-image-{$key}", $filepath);
    $vars["{$key}_raw"] = file_create_url($filepath);
  }
}

/**
 * Make image markup overridable.
 */
function theme_designkit_image($name, $filepath) {
  return theme('imagecache', "designkit-image-{$name}", $filepath);
}

/**
 * Theme colorpicker element.
 */
function theme_designkit_colorpicker($element) {
  // Add Farbtastic color picker
  drupal_add_css('misc/farbtastic/farbtastic.css', 'module', 'all', FALSE);
  drupal_add_js('misc/farbtastic/farbtastic.js');
  drupal_add_js(drupal_get_path('module', 'designkit') .'/designkit.js');

  $output = theme('textfield', $element);
  $output .= "<div id='{$element['#id']}-colorpicker' style='display:none;'></div>";
  return $output;
}