<?php
// $Id: crayon.module,v 1.1 2010/08/10 16:15:27 yhahn Exp $

/**
 * Implementation of hook_enable().
 * Weight crayon to be after a set of modules.
 */
function crayon_enable() {
  $weight = db_result(db_query("SELECT MAX(weight) FROM {system} WHERE type = 'module' AND name IN('casetracker', 'og', 'spaces_og')"));
  if (!empty($weight)) {
    db_query("UPDATE {system} SET weight = %d WHERE name = 'crayon'", ($weight + 1));
  }
}

/**
 * Implementation of hook_views_api().
 */
function crayon_views_api() {
  return array('api' => '2');
}

/**
 * Implementation of hook_theme().
 */
function crayon_theme() {
  $items = array();
  $items['crayon_popup'] = array(
    'arguments' => array('label' => '', 'color' => NULL),
    'template' => 'crayon-popup',
    'file' => 'crayon.theme.inc',
  );
  $items['crayon_swatch'] = array(
    'arguments' => array('label' => '', 'color' => NULL, 'popup' => NULL, 'path' => NULL, 'options' => array()),
    'template' => 'crayon-swatch',
    'file' => 'crayon.theme.inc',
  );
  return $items;
}

/**
 * Determine whether a given string is a css RGB color value.
 */
function crayon_is_color($value) {
  return preg_match('/(#[0-9a-f]{6}|#[0-9a-f]{3})/i', $value);
}

/**
 * Use mod math to generate a palette index.
 */
function crayon_generate_index($id, $palette_size = 42) {
  static $crayon = array();
  static $strings = array();

  // Do a string to int conversion if necessary.
  // @TODO: Determine the best distinct string to distinct int conversion here.
  if (!is_numeric($id)) {
    if (!isset($strings[$id])) {
      $strings[$id] = abs(crc32($id));
    }
    $id = $strings[$id];
  }

  // Return the modulo crayon color id.
  if (!isset($crayon[$id])) {
    $modulo = $id % $palette_size;
    // Try 5 times to avoid color collision.
    $try = 0;
    while (in_array($modulo, $crayon, TRUE) && $try < 5) {
      $modulo = ($modulo + 1) % 42;
      $try++;
    }
    $crayon[$id] = $modulo;
  }
  return $crayon[$id];
}

/**
 * Generate an acronym from a given string.
 */
function crayon_generate_acronym($string, $reset = FALSE) {
  static $cache = array();

  if (!isset($cache[$string]) || $reset) {
    $split = preg_split('/[ .-]+/', $string, -1, PREG_SPLIT_NO_EMPTY);
    $acro = '';

    // Capital-letter based acronyms
    if (preg_match('/[0-9A-Z]+/', $string)) {

      // Eliminate small words
      foreach ($split as $k => $chunk) {
        // No caps or numbers, trash it
        if (!preg_match('/[0-9A-Z]+/', $chunk)) {
          unset($split[$k]);
        }
      }
      reset($split);

      // Multiword titles -- form acronym from key characters.
      if (count($split) > 1) {
        foreach ($split as $chunk) {
          $char = array();
          preg_match_all('/[0-9A-Z]/', $chunk, $char);
          $acro .= implode('', $char[0]);
        }
      }
      // 1 word titles
      else {
        $split = array_shift($split);
        $char = array();
        preg_match_all('/[0-9A-Z]/', $split, $char);
        // Use caps as the acronym, but if there's only 1 cap use the whole string.
        $acro = count($char[0]) > 1 ? implode('', $char[0]) : $split;
      }
    }
    // Lower case title, bail and use first word
    else {
      // Multi-word -- use first letter of each
      if (count($split) > 1) {
        foreach ($split as $chunk) {
          $acro .= drupal_substr($chunk, 0, 1);
        }
      }
      // Bail, use first word
      else {
        $acro = current($split);
      }
    }
    $cache[$string] = $acro;
  }

  return $cache[$string];
}