book.module

<?php
// $Id$

function book_node($field) {
  global $user;

  $info["name"] = t("book page");
  $info["description"] = t("A book is a collaborative effort on a certain subject. Users collaborate writing the pages of the book, positioning the pages in the right order, and reviewing or modifying pages previously written.  You can add a new book page or you can modify existing pages.");

  return $info[$field];
}

function book_access($op, $node) {
  global $user;

  if ($op == "view") {
    /*
    ** Everyone can access all published book pages whether these pages
    ** are still waiting for approval or not.  We might not always want
    ** to display pages that are waiting for approval, but we take care
    ** of that problem in the book_view() function.
    */

    return $node->status;
  }

  if  ($op == "create") {
    return 1;
  }

  if ($op == "update") {

    /*
    ** Everyone can upate a book page if there are no suggested updates
    ** of that page waiting for approval and as long as the "create new
    ** revision"-bit is set; that is, only updates that don't overwrite
    ** the current or pending information are allowed.
    */

    return !$node->moderate && $node->revision;
  }
}

function book_link($type) {
  if ($type == "page" && user_access("access content")) {
    $links[] = "<a href=\"module.php?mod=book\">". t("collaborative book") ."</a>";
  }

  return $links ? $links : array();
}

function book_load($node) {
  $book = db_fetch_object(db_query("SELECT parent, weight, revision FROM book WHERE nid = '$node->nid'"));
  return $book;
}

function book_insert($node) {
  db_query("INSERT INTO book (nid, parent, weight) VALUES ('$node->nid', '$node->parent', '$node->weight')");
}

function book_update($node) {
  db_query("UPDATE book SET parent = '$node->parent', weight = '$node->weight' WHERE nid = '$node->nid'");
}

function book_delete($node) {
  db_query("DELETE FROM book WHERE nid = '$node->nid'");
}

function book_save($node) {
  if ($node->nid) {
    if (user_access("administer nodes")) {
      /*
      ** If a node administrator updates a book page, we don't create a
      ** new revision unless we are explicitly instructed to.
      */

      return array("parent", "weight");
    }
    else {
      /*
      ** If a regular user updates a book page, we always create a new
      ** revision.  All new revisions have to be approved (moderation)
      ** and are not promoted by derault.
      */

      return array("created" => time(), "moderate" => 1, "parent", "promote" => 0, "score" => 0, "status" => 1, "users" => "", "revisions", "votes" => 0, "weight");
    }
  }
  else {
    return array("moderate" => 1, "parent", "promote" => 0, "status" => 1, "weight");
  }
}

function book_form($node, $help, $error) {
  global $user;

  $output .= form_select(t("Parent"), "parent", $node->parent, book_toc(), t("The parent subject or category the page belongs in."));
  $output .= form_textarea(t("Content"), "body", $node->body, 60, 20, t("Allowed HTML tags") .": ". htmlspecialchars(variable_get("allowed_html", "")));
  $output .= form_textarea(t("Log message"), "history", $node->history, 60, 5, t("An explanation of the additions or updates being made to help the group understand your motivations."));

  if (user_access("administer nodes")) {
    $output .= form_select(t("Weight"), "weight", $node->weight, array(0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30), t("The heavier nodes will sink and the lighter nodes will be positioned nearer the top."));
  }
  else {

    /*
    ** Carry out some explanation or submission guidelines:
    */

    $help = t("\"update book page\"-help: to be written!  It should explain the basic idea behind our collaborative book and how their update helps to improve the quality of the book.  Also mention that all updates are subject to moderation or review.  Any who can put this into a fluent English help text?");

    /*
    ** If a regular user updates a book page, we create a new revision
    ** authored by that user:
    */

    $output .= form_hidden("revision", 1);

    $node->uid = $user->uid;    // $node is passed by reference
    $node->name = $user->name;

  }

  return $output;
}

function book_location($node, $nodes = array()) {
  $parent = db_fetch_object(db_query("SELECT n.nid, n.title, b.parent FROM node n LEFT JOIN book b ON n.nid = b.nid WHERE n.nid = '$node->parent'"));
  if ($parent->title) {
    $nodes = book_location($parent, $nodes);
    array_push($nodes, $parent);
  }
  return $nodes;
}

function book_view($node, $main = 0) {
  global $theme, $mod;

  /*
  ** Always display the most recently approved revision of a node
  ** unless we have to display it in the context of the moderation
  ** queue.
  */

  if ($node->moderate && $mod != "queue") {
    $node = node_revision_load($node, end(node_revision_list($node)));
  }

  /*
  ** Display the node.  If not displayed on the main page, we render
  ** the node as a page in the book with extra links to the previous
  ** and the next page.
  */

  if ($main) {
    $theme->node($node, $main);
  }
  else {
    if ($node->nid && $node->parent) {
      $next = db_fetch_object(db_query("SELECT n.nid, n.title FROM node n LEFT JOIN book b ON n.nid = b.nid WHERE n.status = 1 AND b.parent = '$node->parent' AND (b.weight > '$node->weight' OR (b.weight = '$node->weight' AND n.title > '". check_query($node->title) ."')) ORDER BY b.weight ASC, n.title ASC"));
      $prev = db_fetch_object(db_query("SELECT n.nid, n.title FROM node n LEFT JOIN book b ON n.nid = b.nid WHERE n.status = 1 AND b.parent = '$node->parent' AND (b.weight < '$node->weight' OR (b.weight = '$node->weight' AND n.title < '". check_query($node->title) ."')) ORDER BY b.weight DESC, n.title DESC"));
    }

    $output .= "<table border=\"0\" cellpadding=\"0\" cellspacing=\"0\" width=\"100%\">\n";

    if ($node->title) {
      foreach (book_location($node) as $level) {
        $location .= "$indent <a href=\"node.php?id=$level->nid\">$level->title</a><br />";
        $indent .= "-";
      }

      $output .= " <tr><td colspan=\"2\">$location</td><td align=\"right\"><a href=\"module.php?mod=node&op=edit&id=$node->nid\">". t("update this book page") ."</a></td></tr>";
      $output .= " <tr><td colspan=\"3\"><hr /></td></tr>";
      $output .= " <tr><td colspan=\"3\"><b><big>". check_output($node->title) ."</big></b>". ($node->body ? "<br /><small><i>". sprintf(t("Last updated by %s on %s"), format_name($node), format_date($node->created)) ."</i></small> " : "") ."</td></tr>";
    }

    if ($node->body) {
      $output .= " <tr><td colspan=\"3\"><br />". check_output($node->body, 1) ."</td></tr>";
    }

    if ($node->nid) {
      $output .= " <tr><td colspan=\"3\"><br />". book_tree($node->nid) ."</td></tr>";
    }

    $output .= " <tr><td colspan=\"3\"><hr /></td></tr>";
    $output .= " <tr><td align=\"left\" width=\"33%\">". ($prev ? "<a href=\"node.php?id=$prev->nid\">". t("previous") ."</a>" : t("previous")) ."</td><td align=\"center\" width=\"34%\"><a href=\"module.php?mod=book\">index</a></td><td align=\"right\" width=\"33%\">". ($next ? "<a href=\"node.php?id=$next->nid\">". t("next") ."</a>" : t("next")) ."</td></tr>";
    $output .= " <tr><td align=\"left\" width=\"33%\">". ($prev ? "<small>". check_output($prev->title) ."</small>" : "&nbsp;") ."</td><td align=\"center\" width=\"34%\">". ($node->parent ? "<a href=\"node.php?id=$node->parent\">". t("up") ."</a>" : t("up")) ."</td><td align=\"right\" width=\"33%\">". ($next ? "<small>". check_output($next->title) ."</small>" : "&nbsp;") ."</td></tr>";
    $output .= "</table>";

    $theme->box(t("Handbook"), $output);
  }
}

function book_toc($parent = "", $indent = "", $toc = array()) {

  /*
  ** Select all child nodes:
  */

  $result = db_query("SELECT n.nid, n.title FROM node n LEFT JOIN book b ON n.nid = b.nid WHERE n.type = 'book' AND n.status = 1 AND b.parent = '$parent' ORDER BY b.weight");

  /*
  ** Add the root node:
  */

  if (user_access("administer nodes")) {
    $toc[0] = "<root>";
  }

  /*
  ** Build the table of contents:
  */

  while ($node = db_fetch_object($result)) {
    $toc[$node->nid] = "$indent $node->title";
    $toc = book_toc($node->nid, "$indent-", $toc);
  }

  return $toc;
}

function book_tree($parent = "", $depth = 0) {

  if ($depth < 3) {
    /*
    ** Select all child nodes and render them into a table of contents:
    */

    $result = db_query("SELECT n.nid FROM node n LEFT JOIN book b ON n.nid = b.nid WHERE n.type = 'book' AND b.parent = '$parent' ORDER BY b.weight, n.title");

    while ($page = db_fetch_object($result)) {
      // load the node:
      $node = node_load(array("nid" => $page->nid));

      // take the most recent approved revision:
      if ($node->moderate) {
        $node = node_revision_load($node, end(node_revision_list($node)));
      }

      // output the content:
      $output .= "<li><a href=\"node.php?id=$node->nid\">". check_output($node->title) ."</a></li>";

      // build the sub-tree of each child:
      $output .= book_tree($node->nid, $depth + 1);
    }

    $output = "<ul>$output</ul>";
  }

  return $output;
}

function book_render() {
  global $theme;

  $result = db_query("SELECT n.nid FROM node n LEFT JOIN book b ON n.nid = b.nid WHERE b.parent = 0 AND n.status = 1 ORDER BY b.weight");

  while ($page = db_fetch_object($result)) {
    // load the node:
    $node = node_load(array("nid" => $page->nid));

    // take the most recent approved revision:
    if ($node->moderate) {
      $node = node_revision_load($node, end(node_revision_list($node)));
    }

    // output the content:
    $output .= "<dt><a href=\"node.php?id=$node->nid\">". check_output($node->title) ."</a></dt><dd>". check_output($node->body, 1) ."<br /><br /></dd>";
  }

  $theme->header();
  $theme->box(t("Handbook"), "<dl>$output</dl>");
  $theme->footer();
}

function book_page() {
  global $op, $id, $theme;

  if (user_access("access content")) {
    switch ($op) {
      case "feed":
        print book_export_html($id, $depth = 1);
        break;
      default:
        book_render();
    }
  }
  else {
    $theme->header();
    $theme->box(t("Access denied"), message_access());
    $theme->footer();
  }
}

function book_export_html($id = "", $depth = 1) {
  $result = db_query("SELECT n.nid FROM node n LEFT JOIN book b ON n.nid = b.nid WHERE n.type = 'book' AND n.status = 1 AND n.nid = '". check_input($id) ."'");

  while ($page = db_fetch_object($result)) {
    // load the node:
    $node = node_load(array("nid" => $page->nid));

    // take the most recent approved revision:
    if ($node->moderate) {
      $node = node_revision_load($node, end(node_revision_list($node)));
    }

    // output the content:
    $output .= "<h$depth>". check_output($node->title) ."</h$depth>";

    if ($node->body) {
      $output .= "<blockquote>". check_output($node->body, 1) ."</blockquote>";
    }
  }

  $output .= book_export_html_recursive($id, $depth);

  return $output;
}

function book_export_html_recursive($parent = "", $depth = 1) {
  $result = db_query("SELECT n.nid FROM node n LEFT JOIN book b ON n.nid = b.nid WHERE n.type = 'book' AND n.status = 1 AND b.parent = '$parent' ORDER BY b.weight");

  while ($page = db_fetch_object($result)) {
    // load the node:
    $node = node_load(array("nid" => $page->nid));

    // take the most recent approved revision:
    if ($node->moderate) {
      $node = node_revision_load($node, end(node_revision_list($node)));
    }

    // output the content:
    $output .= "<h$depth>". check_output($node->title) ."</h$depth>";

    if ($node->body) {
      $output .= "<blockquote>". check_output($node->body, 1) ."</blockquote>";
    }

    $output .= book_export_html_recursive($node->nid, $depth + 1);
  }

  return $output;
}

?>