drupal/modules/book/book.module

<?php

class Book {
  function Book($book) {
    $this = new Node($book);
    $this->body = $book[body];
    $this->parent = $book[parent];
    $this->weight = $book[weight];
  }
}

function book_perm() {
  return array("edit book");
}

function book_status() {
  return array(dumped, expired, queued, posted);
}

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

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

  if ($main) {
    $theme->node($node, $main);
  }
  else {
    if ($node->nid && $node->parent) {
      $list = book_parent_query($node->parent);
      $next = db_fetch_object(db_query("SELECT n.nid, n.title FROM node n LEFT JOIN book b ON n.nid = b.nid AND n.lid = b.lid WHERE n.status = '$status[posted]' AND $list AND b.weight > '$node->weight' ORDER BY b.weight ASC"));
      $prev = db_fetch_object(db_query("SELECT n.nid, n.title FROM node n LEFT JOIN book b ON n.nid = b.nid AND n.lid = b.lid WHERE n.status = '$status[posted]' AND $list AND b.weight < '$node->weight' ORDER BY b.weight 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\">". node_control($node) ."</TD></TR>\n";
      $output .= " <TR><TD COLSPAN=\"3\"><HR></TD></TR>";
      $output .= " <TR><TD COLSPAN=\"3\"><B><BIG>". check_output($node->title) ."</BIG></B>". ($node->body ? "<BR><SMALL><I>Last updated by ". format_username($node->userid) ." on ". format_date($node->timestamp) ."</I></SMALL> " : "") ."</TD></TR>\n";
    }

    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>\n";
    $output .= " <TR><TD ALIGN=\"left\" WIDTH=\"33%\">". ($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>\n";
    $output .= "</TABLE>\n";

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

function book_search($keys) {
  global $status, $user;
  $result = db_query("SELECT n.*, u.userid FROM node n LEFT JOIN book b ON n.nid = b.nid AND n.lid = b.lid LEFT JOIN users u ON n.author = u.id WHERE n.type = 'book' AND n.status = '$status[posted]' AND (n.title LIKE '%". check_input($keys) ."%' OR b.body LIKE '%". check_input($keys) ."%') ORDER BY n.timestamp DESC LIMIT 20");
  while ($node = db_fetch_object($result)) {
    $find[$i++] = array("title" => check_output($node->title), "link" => (user_access($user, "add and edit nodes") ? "admin.php?mod=node&type=book&op=edit&id=$node->nid" : "node.php?id=$node->nid"), "user" => $node->userid, "date" => $node->timestamp);
  }
  return $find;
}

function book_parent_query($parent) {
  if ($parent != "") {
    $list = array();
    foreach (book_parent($parent) as $pid) array_push($list, "b.parent = $pid");
  }
  else {
    $list = array("b.parent = ''");
  }
  return "(". implode(" OR ", $list) .")";
}

function book_toc($parent = "", $indent = "", $toc = array()) {
  global $status, $user;

  // select all child nodes:
  $result = db_query("SELECT n.*, b.* FROM node n LEFT JOIN book b ON n.nid = b.nid AND n.lid = b.lid WHERE n.type = 'book' AND n.status = '$status[posted]' AND ". book_parent_query($parent) ." ORDER BY b.weight");

  // add root node:
  if (user_access($user, "add and edit nodes")) {
    $toc[0] = "&nbsp;";
  }

  // build 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_form($edit = array()) {
  global $REQUEST_URI, $user;

  if ($edit[title]) {
    $form .= book_view(new Book(node_preview($edit)));
  }

  $form .= form_item(t("Author"), format_username(($edit[userid] ? $edit[userid] : $user->userid)));
  $form .= form_hidden(userid, $edit[userid]);
  $form .= form_textfield(t("Subject"), "title", $edit[title], 50, 64);

  if ($edit[pid] > 0) {
    $form .= form_hidden("pid", $edit[pid]);
  }
  else {
    $form .= form_select(t("Parent"), "parent", $edit[parent], book_toc(), t("The parent subject or category the page belongs in."));
  }

  $form .= form_textarea(t("Content"), "body", $edit[body], 70, 20, t("Allowed HTML tags") .": ". htmlspecialchars(variable_get("allowed_html", "")));
  $form .= form_textarea(t("Log message"), "log", $edit[log], 70, 5, t("An explanation of the additions or updates being made to help the group understand your motivations."));

  if (user_access($user, "add and edit nodes")) {
    $form .= form_select(t("Weight"), "weight", $edit[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."));
  }

  if ($edit[nid] > 0) {
    $form .= form_hidden("nid", $edit[nid]);
  }

  if ($edit && !$edit[title]) {
    $form .= "<FONT COLOR=\"red\">". t("Warning: you did not supply a title.") ."</FONT><P>\n";
    $form .= form_submit(t("Preview"));
  }
  else {
    $form .= form_submit(t("Preview"));
    $form .= form_submit(t("Submit"));
  }

  return form($REQUEST_URI, $form);
}

function book_save($edit) {
  global $status, $user;

  if (!$edit[nid]) {
    node_save($edit, array(author => $user->id, body, comment => variable_get("book_comment", 0), log, moderate => variable_get("book_moderate", ""), parent, pid, promote => variable_get("book_promote", 0), score => 0, status => variable_get("book_status", $status[queued]), timestamp => time(), title, type => "book", votes => 0, weight));
  }
  else if (user_access($user, "add and edit nodes")) {
    node_save($edit, array(body, log, parent, title, type => "book", weight));
  }
}

function book_delete($node) {
  if ($node->pid && $node->status == node_status("posted")) {
    db_query("UPDATE node SET status = '". node_status("posted") ."' WHERE nid = '$node->pid'");
  }
}

function book_insert($node) {
  if ($node->pid && $node->status == node_status("posted")) {
    db_query("UPDATE node SET status = '". node_status("expired") ."' WHERE nid = '$node->pid'");
  }
}

function book_update($node) {
  if ($node->pid && $node->status == node_status("posted")) {
    db_query("UPDATE node SET status = '". node_status("expired") ."' WHERE nid = '$node->pid'");
  }
}

function book_parent($nid) {
  global $status;
  if ($node = node_get_object(array("nid" => $nid))) {
    $list[$nid] = $nid;
  }
  if ($node->pid) {
    $list = array_merge($list, book_parent($node->pid));
  }
  return $list ? $list : array();
}

function book_tree($parent = "", $depth = 0) {
  global $PHP_SELF, $status;

  if ($depth < 3 || strstr($PHP_SELF,"admin.php")) {
    // select all child nodes:
    $result = db_query("SELECT n.*, b.* FROM node n LEFT JOIN book b ON n.nid = b.nid AND n.lid = b.lid WHERE n.type = 'book' AND n.status = '$status[posted]' AND ". book_parent_query($parent) ." ORDER BY b.weight");

    // render output:
    while ($node = db_fetch_object($result)) {
      $output .= "<LI><A HREF=\"node.php?id=$node->nid\">". check_output($node->title) ."</A>". ($PHP_SELF == "/admin.php" ? " <SMALL>(weight: $node->weight/$node->parent, status: $node->status) (<A HREF=\"admin.php?mod=node&type=book&op=edit&id=$node->nid\">edit</A>)</SMALL>" : "") ."</LI>\n";
      $output .= book_tree($node->nid, $depth + 1);
    }
    $output = "<UL>$output</UL>";
  }
  return $output;
}

function book_admin() {
  global $user;
  if (user_access($user, "edit book")) {
    print book_tree();
  }
  else {
    print message_access();
  }
}

function book_page() {
  global $user, $status, $theme;

  if (user_access($user, "view content")) {
    $result = db_query("SELECT n.*, b.* FROM node n LEFT JOIN book b ON n.nid = b.nid AND n.lid = b.lid WHERE b.parent = 0 AND n.status = $status[posted] ORDER BY b.weight");

    while ($node = db_fetch_object($result)) {
      $output .= "<DT><A HREF=\"node.php?id=$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();
  }
  else {
    $theme->header();
    $theme->box(t("Access denied"), message_access());
    $theme->footer();
  }
}

function book_edit($id) {
  global $status;

  if ($node = node_get_object(array("nid" => $id))) {
    if ($node->status != $status[posted]) {
      return t("You can only update accepted pages: pages that are still queued or already expired can not be updated.");
    }
    else if (db_result(db_query("SELECT COUNT(n.nid) FROM node n LEFT JOIN book b ON n.nid = b.nid AND n.lid = b.lid WHERE b.pid = '$node->nid' AND n.status = '$status[queued]'"))) {
      return t("There is already an update for this node in the queue: we can only process one update at once.");
    }
    else {
      return book_form(array(nid => -1, pid => $id, title => $node->title, body => $node->body, parent => $node->parent));
    }
  }
}

function book_user() {
  global $edit, $id, $op, $theme, $user;

  $title = t("Submit");

  switch($op) {
    case "update":
      $theme->box($title, book_edit($id));
      break;
    case t("Preview"):
      $theme->box($title, book_form($edit));
      break;
    case t("Submit"):
      book_save($edit);
      $theme->box($title, t("Thank you for your submission."));
      break;
    default:
      $theme->box($title, book_form());
  }
}

function book_export_html($parent = "", $depth = 0) {
  global $status;

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

  while ($node = db_fetch_object($result)) {
    $output .= "<H$depth>". check_output($node->title) ."</H$depth>";
    if ($node->body) $output .= check_output($node->body, 1);
    if ($node->pid) $output .= book_export_html($node->pid, $depth + 1);
    $output .= book_export_html($node->nid, $depth + 1);
  }
  return $output;
}

function book_export($uri) {
  $uri = explode("&", $uri);
  if ($uri[0] == "book") {
    print book_export_html($uri[1], $depth = 1);
  }
}

?>