<?php
// $Id: designkit.module,v 1.1 2009-12-14 20:57:19 yhahn Exp $

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

/**
 * Turn design choices into theme variables.
 */
function designkit_preprocess_page(&$vars) {
  $info = designkit_get_info();
  if (!empty($info['designkit']['color'])) {
    $color = variable_get('designkit_color', $info['designkit']['color']);
    if ($color && 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', $color);
    }
  }
  if (!empty($info['designkit']['logo'])) {
    $logo = variable_get('designkit_logo', array());
    foreach ($logo 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)) {
        $vars[$name] = theme('designkit_logo', $name, $file->filepath);
      }
    }
  }
}

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

  // Generate imagecache presets per logo entry in theme info.
  $info = designkit_get_info();
  if (!empty($info['designkit']['logo'])) {
    foreach ($info['designkit']['logo'] as $name => $params) {
      list($action, $dimensions) = explode(':', $params);
      list($width, $height) = explode('x', $dimensions);
      $valid_actions = imagecache_action_definitions();
      if (isset($valid_actions[$action]) && is_numeric($width) && is_numeric($height)) {
        $presets["designkit-logo-{$name}"] = array (
          'presetname' => "designkit-logo-{$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.
 */
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.
 */
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);

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

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