#!/usr/bin/php
<?php

// $Id$
// $Name$

/**
 * @file
 * For a given CVS identifier, convert all occurances of it as a tag
 * into a branch.
 *
 * @author Derek Wright (http://drupal.org/user/46549)
 *
 */

// ------------------------------------------------------------
// Required customization
// ------------------------------------------------------------

// The root of your Drupal installation, so we can properly bootstrap
// Drupal. This should be the full path to the directory that holds
// your index.php file, the "includes" subdirectory, etc.
$drupal_root = '/var/www/drupal.org/htdocs';

// The name of your site. Required so that when we bootstrap Drupal in
// this script, we find the right settings.php file in your sites folder. 
// For example, on drupal.org:
// $site_name = 'drupal.org';
$site_name = 'drupal.org';

// The CVSROOT for the repository this script will be packaging
// releases from.  For example, on drupal.org:
$cvs_root = ':pserver:cvsadmin@cvs.drupal.org:/cvs/drupal-contrib';

// Root of the temporary directory where you want packages to be
// made. Subdirectories will be created depending on the task.
$tmp_root = '/tmp/cvs-convert/drupal';


// ------------------------------------------------------------
// Optional customization
// ------------------------------------------------------------

// --------------
// External tools
// --------------
// If you want this program to always use absolute paths for all the
// tools it invokes, provide a full path for each one. Otherwise,
// the script will find these tools in your PATH.
$cvs = '/usr/bin/cvs';
$rm = '/bin/rm';


// ------------------------------------------------------------
// Initialization
// (Real work begins here, nothing else to customize)
// ------------------------------------------------------------

// Check if all required variables are defined
$vars = array(
  'drupal_root' => $drupal_root,
  'site_name' => $site_name,
  'cvs_root' => $cvs_root,
  'tmp_root' => $tmp_root,
);
foreach ($vars as $name => $val) {
  if (empty($val)) {
    print "ERROR: \"\$$name\" variable not set, aborting\n";
    $fatal_err = true;
  }
}
if ($fatal_err) {
  exit(1);
}

// Find what tag we're trying to convert
if ($argv[1]) {
  $tag = $argv[1];
}
else {
  print "ERROR: You must specify the tag to convert to a branch\n";
  exit(1);
}

putenv("CVSROOT=$cvs_root");
$script_name = $argv[0];

// Setup variables for Drupal bootstrap
$_SERVER['HTTP_HOST'] = $site_name;
$_SERVER['REQUEST_URI'] = '/' . $script_name;
$_SERVER['SCRIPT_NAME'] = '/' . $script_name;
$_SERVER['PHP_SELF'] = '/' . $script_name;
$_SERVER['SCRIPT_FILENAME'] = $_SERVER['PWD'] . '/' . $script_name;
$_SERVER['PATH_TRANSLATED'] = $_SERVER['SCRIPT_FILENAME'];

if (!chdir($drupal_root)) {
  print "ERROR: Can't chdir($drupal_root): aborting.\n";
  exit(1);
}

require_once 'includes/bootstrap.inc';
drupal_bootstrap(DRUPAL_BOOTSTRAP_FULL);

initialize_tmp_dir();
initialize_repository_info();

$conversions = array();
convert_tags($tag);


// ------------------------------------------------------------
// Functions: main work
// ------------------------------------------------------------

function convert_tags($tag) {
  global $conversions;
  $query = db_query("SELECT pp.uri, prn.nid, prn.pid, prn.tag, cp.directory, cp.rid FROM {project_release_nodes} prn INNER JOIN {project_projects} pp ON prn.pid = pp.nid INNER JOIN {node} np ON prn.pid = np.nid INNER JOIN {project_release_projects} prp ON prp.nid = prn.pid INNER JOIN {cvs_projects} cp ON prn.pid = cp.nid INNER JOIN {cvs_tags} ct ON ct.nid = prn.pid AND ct.tag = prn.tag WHERE prn.tag='%s' AND ct.branch = 0 ORDER BY cp.directory", $tag);

  $num_converted = 0;
  $num_considered = 0;
  while ($release = db_fetch_object($query)) {
    $uri = $release->uri;
    $tag = $release->tag;
    $nid = $release->nid;
    wd_msg(t("Working on converting %tag for %uri", array('%uri' => $uri, '%tag' => $tag)), l(t('view'), 'node/' . $nid));
    $uri = escapeshellcmd($uri);
    $tag = escapeshellcmd($tag);
    $dir = escapeshellcmd(trim($release->directory, '/'));
    if (convert_tag($tag, $nid, $uri, $dir, $release->rid)) {
      $num_converted++;
    }
    $num_considered++;
  }
  if ($num_converted) {
    wd_msg(t("Done converting %tag tags into branches: !num_converted converted, !num_considered considered.", array('%tag' => $tag, '!num_converted' => $num_converted, '!num_considered' => $num_considered)) . "<pre>\n" . implode("\n", $conversions));
  }
}

function convert_tag($tag, $nid, $uri, $dir, $rid) {
  global $tmp_dir, $repositories, $conversions;
  global $cvs, $rm;
  
  if (!drupal_chdir($tmp_dir)) {
    return false;
  }

  $view_link = l(t('view'), 'node/' . $nid);
  $tmp_tag = $tag .'_';
  $cvs_dir = $repositories[$rid]['modules'] . '/' . $dir;

  // Don't use drupal_exec or return if this fails, we expect it to be empty.
  exec("$rm -rf $tmp_dir/$uri");
  @mkdir("$tmp_dir/$uri");
  if (!drupal_chdir("$tmp_dir/$uri")) {
    return false;
  }

  drupal_exec("$cvs -q checkout -r $tag $cvs_dir");
  if (!drupal_chdir($cvs_dir)) {
    return false;
  }

  db_query("UPDATE {project_release_nodes} SET tag='%s' WHERE nid = %d", $tmp_tag, $nid);
  drupal_exec("$cvs tag -d $tag");
  drupal_exec("$cvs tag -b $tag");
  db_query("UPDATE {project_release_nodes} SET tag='%s' WHERE nid = %d", $tag, $nid);

  $conversions[] = "<a href=\"/node/$nid\">$dir</a>";
  return true;
}


// ------------------------------------------------------------
// Functions: utility methods
// ------------------------------------------------------------

/**
 * Wrapper for exec() that logs errors to the watchdog.
 * @param $cmd
 *   String of the command to execute (assumed to be safe, the caller is
 *   responsible for calling escapeshellcmd() if necessary).
 * @return true if the command was successful (0 exit status), else false.
 */
function drupal_exec($cmd) {
  // Made sure we grab stderr, too...
  exec("$cmd 2>&1", $output, $rval);
  if ($rval) {
    wd_err(t("ERROR: %cmd failed with status !rval", array('%cmd' => $cmd, '!rval' => $rval)) . '<pre>' . implode("\n", array_map('htmlspecialchars', $output)));
    return false;
  }
  wd_msg(t("%cmd success", array('%cmd' => $cmd)) . '<pre>' . implode("\n", array_map('htmlspecialchars', $output)));
  return true;
}

/**
 * Wrapper for chdir() that logs errors to the watchdog.
 * @param $dir Directory to change into.
 * @return true if the command was successful (0 exit status), else false.
 */
function drupal_chdir($dir) {
  if (!chdir($dir)) {
    wd_err(t("ERROR: Can't chdir(@dir)", array('@dir' => $dir)));
    return false;
  }
  return true;
}

/**
 * Wrapper function for watchdog() to log notice messages. Uses a
 * different watchdog message type depending on the task (branch vs. tag).
 */
function wd_msg($msg, $link = NULL) {
  watchdog('cvs_convert' . $task, $msg, WATCHDOG_NOTICE, $link);
}

/**
 * Wrapper function for watchdog() to log error messages.
 */
function wd_err($msg, $link = NULL) {
  watchdog('cvs_convert_error', $msg, WATCHDOG_ERROR, $link);
}

/**
 * Initialize the tmp directory.
 */
function initialize_tmp_dir() {
  global $tmp_dir, $tmp_root;
  global $rm;

  if (!is_dir($tmp_root)) {
    wd_err(t("ERROR: tmp_root: @dir is not a directory", array('@dir' => $tmp_root)));
    exit(1);
  }

  $tmp_dir = $tmp_root . '/tag-convert';
  if (is_dir($tmp_dir)) {
    // Make sure we start with a clean slate
    drupal_exec("$rm -rf $tmp_dir/*");
  }
  else if (!@mkdir($tmp_dir)) {
    wd_err(t("ERROR: mkdir(@dir) failed", array('@dir' => $tmp_dir)));
    exit(1);
  }
}

/**
 * Initialize info from the {cvs_repositories} table, since there are
 * usually only a tiny handful of records, and it'll be faster to do
 * whatever we need via php than another JOIN...
 */
function initialize_repository_info() {
  global $repositories;
  $query = db_query("SELECT rid, root, modules, name FROM {cvs_repositories}");
  while ($repo = db_fetch_object($query)) {
    $repositories[$repo->rid] = array('root' => $repo->root, 'modules' => $repo->modules, 'name' => $repo->name);
  }
}