<?php

/*
 * @file
 * Technorati module for Drupal 6.x.
 *
 * This module enables Technorati (http://technorati.com) tags for Drupal
 * node. Tags can be stored in a separate database table or can be taken from
 * the taxonomy tags.
 *
 * Copyright (c) 2006 http://2bits.com
 * Copyright (c) 2008 Jan Dittberner <jan@dittberner.info>
 */

define('TECHNORATI_NODE_TYPE',       'technorati_node_type_');

define('TECHNORATI_MODE_NONE',       0);
define('TECHNORATI_MODE_MANUAL',     1);
define('TECHNORATI_MODE_TAXONOMY',   2);
define('TECHNORATI_MODE_BOTH',       3);

define('TECHNORATI_DISPLAY_TYPE',    'technorati_display_type');

define('TECHNORATI_DISPLAY_NONE',    0);
define('TECHNORATI_DISPLAY_TEASER',  1);
define('TECHNORATI_DISPLAY_FULL',    2);
define('TECHNORATI_DISPLAY_BOTH',    3);

/**
 * Implementation of hook_help().
 */
function technorati_help($path, $arg) {
  switch ($path) {
    case 'admin/help#technorati' :
      return '<p>'. t('Enables Technorati tags for selected content types, and pings Technorati when new content is created.') .'</p>';
  }
}

/**
 * Implementation of hook_menu().
 */
function technorati_menu() {
  $items = array();

  $items['admin/settings/technorati'] = array(
      'title' => 'Technorati',
      'description' => 'technorati settings',
      'page callback' => 'drupal_get_form',
      'page arguments' => array('technorati_admin_settings'),
      'access arguments' => array('administer site configuration'),
      'type' => MENU_NORMAL_ITEM
  );
  return $items;
}

/**
 * Form definition for technorati module settings.
 */
function technorati_admin_settings() {
  if (!module_exists('ping')) {
    drupal_set_message(t('This module requires that the %pingmodule be enabled',
      array('%pingmodule' => l('ping module', 'admin/modules'))), 'error');
      return;
  }

  $display_options = array(
    TECHNORATI_DISPLAY_NONE    => t('None'),
    TECHNORATI_DISPLAY_TEASER  => t('Teaser view'),
    TECHNORATI_DISPLAY_FULL    => t('Full page view'),
    TECHNORATI_DISPLAY_BOTH    => t('Both'),
  );

  $node_options = array(
    TECHNORATI_MODE_NONE     => t('None'),
    TECHNORATI_MODE_MANUAL   => t('Manual entry'),
    TECHNORATI_MODE_TAXONOMY => t('Drupal categories'),
    TECHNORATI_MODE_BOTH     => t('Both'),
  );

  $form[TECHNORATI_DISPLAY_TYPE] = array(
    '#type'          => 'select',
    '#title'         => t('How to display the technorati tags'),
    '#default_value' => variable_get(TECHNORATI_DISPLAY_TYPE, TECHNORATI_DISPLAY_FULL),
    '#options'       => $display_options,
    '#description' => t('Select how to display the tags.<ul><li>None: means that the module will not display the tags. The theme can use the $node->technorati object to display the tags anywhere.</li><li>Teaser: means that the tags will only be displayed when the node is in teaser view.</li><li>Full page: means that the tags will only be displayed when the node is in full page view.</li><li>Both: means the tags will be displayed in both teaser and full view.</li></ul>'),
  );

  $form['types'] = array(
    '#type' => 'fieldset',
    '#title' => t('Content types'),
    '#collapsible' => TRUE,
    '#description' => t('Select the type of tags to use for each content type.<ul><li>None: means do not do any Technorati tags for this content type.</li><li>Manual entry: means that the tags have to be entered manually for each node.</li><li>Drupal categories: means that the terms the node belong to will be used as Technorati tags.</li><li>Both: means a combination of manual entries and categories.</li></ul>'),
  );

  foreach (node_get_types() as $node_type => $node_name) {
    $type = TECHNORATI_NODE_TYPE . $node_type;
    $form['types'][$type] = array(
      '#type'          => 'select',
      '#title'         => $node_type,
      '#default_value' => variable_get($type, TECHNORATI_MODE_NONE),
      '#options'       => $node_options,
    );
  }

  return system_settings_form($form);
}

/**
 * Implementation of hook_form_alter().
 */
function technorati_form_alter(&$form, &$form_state, $form_id) {
  if (preg_match('/^(.*)_node_form$/', $form_id, $matches)) {
    // Get the node type we are processing
    $node_type = $matches[1];

    // Check what the technorati mode for that node type
    $mode = variable_get(TECHNORATI_NODE_TYPE . $node_type, TECHNORATI_MODE_NONE);
    switch ($mode) {
      case TECHNORATI_MODE_NONE:
      case TECHNORATI_MODE_TAXONOMY:
        // No need to do anything in the node form
        return;

      case TECHNORATI_MODE_MANUAL:
      case TECHNORATI_MODE_BOTH:
        // We need to inject the texfield for technorati tags in the form
        $tags = '';
        // Load the node and get the technorati tags, if present
        if ($nid = $form['nid']['#value']) {
          $node = node_load($nid);
          if (is_array($node->technorati_tags)) {
            $tags = implode(',', $node->technorati_tags);
          }
        }

        $form['technorati'] = array(
          '#type'        => 'fieldset',
          '#title'       => t('Technorati'),
          '#collapsible' => TRUE,
          '#collapsed'   => TRUE,
        );

        $form['technorati']['technorati_tags'] = array(
          '#type'          => 'textfield',
          '#title'         => t('Technorati tags'),
          '#default_value' => $tags,
          '#size'          => 80,
          '#maxlength'     => 120,
          '#description'   => t('Enter your Technorati tags, separated by commas.'),
        );
    }
  }
}

/**
 * Implementation of hook_theme().
 */
function technorati_theme() {
  return array(
    'technorati_tags' => array(
                               'arguments' => array('tags' => NULL),
    ),
  );
}

/**
 * Implementation of hook_nodeapi().
 */
function technorati_nodeapi(&$node, $op, $a3, $a4) {
  $mode = variable_get(TECHNORATI_NODE_TYPE . $node->type, TECHNORATI_MODE_NONE);
  switch ($mode) {
    case TECHNORATI_MODE_NONE:
    case TECHNORATI_MODE_TAXONOMY:
      // No need to do anything in the node form
      return;
  }

  switch ($op) {
    case 'insert':
      db_query("INSERT INTO {technorati} (nid, tags) VALUES (%d, '%s')",
        $node->nid, serialize(explode(',', $node->technorati_tags)));
      break;

    case 'update':
      db_query('DELETE FROM {technorati} WHERE nid = %d', $node->nid);
      db_query("INSERT INTO {technorati} (nid, tags) VALUES (%d, '%s')",
        $node->nid, serialize(explode(',', $node->technorati_tags)));
      break;

    case 'delete':
      db_query('DELETE FROM {technorati} WHERE nid = %d', $node->nid);
      break;

    case 'load':
      $result = db_query('SELECT tags FROM {technorati} WHERE nid = %d', $node->nid);
      $tags = unserialize(db_result($result));
      if ($tags) {
        return array('technorati_tags' => $tags);
      }
      break;

    case 'view':
      $technorati = array(
        '#value' => theme('technorati_tags', _technorati_process_tags($node)),
        '#weight' => 10,
      );
      $mode = variable_get(TECHNORATI_DISPLAY_TYPE, TECHNORATI_DISPLAY_FULL);
      switch ($mode) {
        case TECHNORATI_DISPLAY_NONE:
          // No inline display. Theme will handle it all.
          break;
        case TECHNORATI_DISPLAY_TEASER:
          // Teaser view only
          if ($a3) {
            $node->content['technorati'] = $technorati;
          }
          break;
        case TECHNORATI_DISPLAY_FULL:
          // Full page view only
          if (!$a3) {
            $node->content['technorati'] = $technorati;
          }
          break;
        case TECHNORATI_DISPLAY_BOTH:
          // Teaser and full page view
          $node->content['technorati'] = $technorati;
          break;
      }
      break;
  }
}

/**
 * Theme function for registered theme 'technorati_tags'.
 */
function theme_technorati_tags($tags) {
  $path = base_path() . drupal_get_path('module', 'technorati') .'/technobubble.gif';
  $output = '<div class="technorati_tags">';
  $output .= '<img src="'. $path .'"/>';
  $output .= '<strong>'. t('Technorati Tags: ') .'</strong>';
  $output .= implode(' ', $tags);
  $output .= '</div>';
  //$output .= '<script type="text/javascript" src="http://technorati.com/embed/CODE.js"></script>';
  return $output;
}

/**
 * This function is called by technorati_nodeapi() with $op 'view' and
 * processes the tags in a node type and technorati mode specific way.
 */
function _technorati_process_tags($node) {
  $mode = variable_get(TECHNORATI_NODE_TYPE . $node->type, TECHNORATI_MODE_NONE);
  switch ($mode) {
    case TECHNORATI_MODE_MANUAL:
      return _technorati_manual($node);

    case TECHNORATI_MODE_TAXONOMY:
      return _technorati_taxonomy($node);

    case TECHNORATI_MODE_BOTH:
      return array_merge(_technorati_taxonomy($node),  _technorati_manual($node));
  }
}

/**
 * This function handles the manually assigned technorati tags of a node. It
 * is called by _technorati_process_tags() for the technorati modes 'manual'
 * and 'both'.
 */
function _technorati_manual($node) {
  $links = array();
  if (is_array($node->technorati_tags)) {
    foreach ($node->technorati_tags as $tag) {
      $links[] = _technorati_link($tag);
    }
  }
  return $links;
}

/**
 * This function handles the taxonomy tags of a node and creates technorati
 * links from them. It is called by _technorati_process_tags() for the
 * technorati modes 'taxonomy' and 'both'.
 */
function _technorati_taxonomy($node) {
  $links = array();
  $terms = taxonomy_node_get_terms($node);
  foreach ($terms as $term) {
    $links[] = _technorati_link($term->name);
  }
  return $links;
}

/**
 * Calls the Technorati ping service at http://rpc.technorati.com/rpc/ping and
 * notifies changes to the given URL.
 */
function technorati_ping($name = '', $url = '') {
  $result = xmlrpc('http://rpc.technorati.com/rpc/ping', 'weblogUpdates.ping', $name, $url);
  if ($result) {
    watchdog("directory ping", 'Successfully notified technorati.com site.', WATCHDOG_NOTICE);
  }
  else {
    watchdog('directory ping', 'Failed to notify technorati.com site.', WATCHDOG_WARNING);
  }
}

/**
 * Remove whitespace between tags, and format the n words making up
 * multi-word tags with (n-1) "+" symbols.
 */
function _technorati_link($tag) {
  $tag = _technorati_wsstrip(str_replace('+', ' ', check_plain($tag)));
  $output  = '<a href="http://technorati.com/tag/';
  $output .= str_replace(" ", "+", $tag);
  $output .= '" rel="tag">';
  $output .= $tag;
  $output .= '</a>';

  return $output;
}

/**
 * Strip whitespace from left and/or right of tags, and reduce multiples
 * to just one.
 *
 * Reference: daggillies's comment on http://www.php.net/trim
 */
function _technorati_wsstrip($str) {
  $str = ereg_replace(' +', ' ', trim($str));
  return ereg_replace("[\r\t\n]", '', $str);
}