<?php {
   
   /**
    **  abook_database.php
    **
    **  Backend for personal addressbook stored in a database,
    **  accessed using the DB-casses in PEAR.
    **
    **  IMPORTANT:  The PEAR modules must be in the include path
    **  for this class to work.
    **
    **  An array with the following elements must be passed to
    **  the class constructor (elements marked ? are optional):
    **
    **     dsn       => database DNS (see PEAR for syntax)
    **     table     => table to store addresses in (must exist)
    **     owner     => current user (owner of address data)
    **   ? writeable => set writeable flag (true/false)
    **
    ** The table used should have the following columns:
    **  owner, nickname, firstname, lastname, email, label
    ** The pair (owner,nickname) should be unique (primary key).
    **
    **  NOTE. This class should not be used directly. Use the
    **        "AddressBook" class instead.
    **/
   
   require_once("DB.php");
   
   class abook_database extends addressbook_backend {
      var $btype = "local";
      var $bname = "database";
      
      var $dsn       = "";
      var $table     = "";
      var $owner     = "";
      var $dbh       = false;
      
      var $writeable = true;
      
      // ========================== Private =======================
      
      // Constructor
      function abook_database($param) {
         $this->sname = _("Personal address book");
         
         if(is_array($param)) {
            if(empty($param["dsn"]) || 
               empty($param["table"]) || 
               empty($param["owner"]))
               return $this->set_error("Invalid parameters");
            
            $this->dsn   = $param["dsn"];
            $this->table = $param["table"];
            $this->owner = $param["owner"];
            
            if(!empty($param["name"]))
               $this->sname = $param["name"];

            if(isset($param["writeable"]))
               $this->writeable = $param["writeable"];

            $this->open(true);
         } else {
            return $this->set_error("Invalid argument to constructor");
         }
      }
      
      
      // Open the database. New connection if $new is true
      function open($new = false) {
         $this->error = "";
         
         // Return true is file is open and $new is unset
         if($this->dbh && !$new)
            return true;
         
         // Close old file, if any
         if($this->dbh) $this->close();
         
         $dbh = DB::connect($this->dsn, true);
         
         if(DB::isError($dbh) || DB::isWarning($dbh)) 
            return $this->set_error(sprintf(_("Database error: %s"),
                                            DB::errorMessage($dbh)));
         
         $this->dbh = $dbh;
         return true;
      }

      // Close the file and forget the filehandle
      function close() {
         $this->dbh->disconnect();
         $this->dbh = false;
      }

      // ========================== Public ========================
     
      // Search the file
      function &search($expr) {
         $ret = array();
         if(!$this->open())
            return false;
         
         // To be replaced by advanded search expression parsing
         if(is_array($expr)) return;

         // Make regexp from glob'ed expression 
         $expr = ereg_replace("\?", "_", $expr);
         $expr = ereg_replace("\*", "%", $expr);
         $expr = $this->dbh->quoteString($expr);
         $expr = "%$expr%";

         $query = sprintf("SELECT * FROM %s WHERE owner='%s' AND ".
                          "(firstname LIKE '%s' OR lastname LIKE '%s')",
                          $this->table, $this->owner, $expr, $expr);
         $res = $this->dbh->query($query);

         if(DB::isError($res)) 
            return $this->set_error(sprintf(_("Database error: %s"),
                                            DB::errorMessage($res)));

         while ($row = $res->fetchRow(DB_FETCHMODE_ASSOC)) {
            array_push($ret, array("nickname"  => $row["nickname"],
                                   "name"      => $row["firstname"] . " " . $row["lastname"],
                                   "firstname" => $row["firstname"],
                                   "lastname"  => $row["lastname"],
                                   "email"     => $row["email"],
                                   "label"     => $row["label"],
                                   "backend"   => $this->bnum,
                                   "source"    => &$this->sname));
         }
         return $ret;
      }
     
      // Lookup alias
      function &lookup($alias) {
         if(empty($alias))
            return array();
         
         $alias = strtolower($alias);

         if(!$this->open())
            return false;
         
         $query = sprintf("SELECT * FROM %s WHERE owner='%s' AND nickname='%s'",
                          $this->table, $this->owner, $alias);

         $res = $this->dbh->query($query);

         if(DB::isError($res)) 
            return $this->set_error(sprintf(_("Database error: %s"),
                                            DB::errorMessage($res)));

         if ($row = $res->fetchRow(DB_FETCHMODE_ASSOC)) {
            return array("nickname"  => $row["nickname"],
                         "name"      => $row["firstname"] . " " . $row["lastname"],
                         "firstname" => $row["firstname"],
                         "lastname"  => $row["lastname"],
                         "email"     => $row["email"],
                         "label"     => $row["label"],
                         "backend"   => $this->bnum,
                         "source"    => &$this->sname);
         }

         return array();
      }

      // List all addresses
      function &list_addr() {
         $ret = array();
         if(!$this->open())
            return false;

         $query = sprintf("SELECT * FROM %s WHERE owner='%s'",
                          $this->table, $this->owner);

         $res = $this->dbh->query($query);

         if(DB::isError($res)) 
            return $this->set_error(sprintf(_("Database error: %s"),
                                            DB::errorMessage($res)));

         while ($row = $res->fetchRow(DB_FETCHMODE_ASSOC)) {
            array_push($ret, array("nickname"  => $row["nickname"],
                                   "name"      => $row["firstname"] . " " . $row["lastname"],
                                   "firstname" => $row["firstname"],
                                   "lastname"  => $row["lastname"],
                                   "email"     => $row["email"],
                                   "label"     => $row["label"],
                                   "backend"   => $this->bnum,
                                   "source"    => &$this->sname));
         }
         return $ret;
      }

      // Add address
      function add($userdata) {
         if(!$this->writeable) 
            return $this->set_error(_("Addressbook is read-only"));

         if(!$this->open())
            return false;
         
         // See if user exist already
         $ret = $this->lookup($userdata["nickname"]);
         if(!empty($ret))
            return $this->set_error(sprintf(_("User '%s' already exist"), 
                                            $ret["nickname"]));

         // Create query
         $query = sprintf("INSERT INTO %s (owner, nickname, firstname, ".
                          "lastname, email, label) VALUES('%s','%s','%s',".
                          "'%s','%s','%s')",
                          $this->table, $this->owner,
                          $this->dbh->quoteString($userdata["nickname"]),
                          $this->dbh->quoteString($userdata["firstname"]), 
                          $this->dbh->quoteString($userdata["lastname"]),
                          $this->dbh->quoteString($userdata["email"]), 
                          $this->dbh->quoteString($userdata["label"]) );

         // Do the insert
         $r = $this->dbh->simpleQuery($query);
         if($r == DB_OK) return true;

         // Fail
         return $this->set_error(sprintf(_("Database error: %s"),
                                         DB::errorMessage($r)));
      }

      // Delete address
      function remove($alias) {
         if(!$this->writeable) 
            return $this->set_error(_("Addressbook is read-only"));

         if(!$this->open())
            return false;
         
         // Create query
         $query = sprintf("DELETE FROM %s WHERE owner='%s' AND (",
                          $this->table, $this->owner);

         $sepstr = "";
         while(list($undef, $nickname) = each($alias)) {
            $query .= sprintf("%s nickname='%s' ", $sepstr,
                              $this->dbh->quoteString($nickname));
            $sepstr = "OR";
         }
         $query .= ")";

         // Delete entry
         $r = $this->dbh->simpleQuery($query);
         if($r == DB_OK) return true;

         // Fail
         return $this->set_error(sprintf(_("Database error: %s"),
                                         DB::errorMessage($r)));
      }

      // Modify address
      function modify($alias, $userdata) {
         if(!$this->writeable) 
            return $this->set_error(_("Addressbook is read-only"));

         if(!$this->open())
            return false;
         
         // See if user exist
         $ret = $this->lookup($alias);
         if(empty($ret))
            return $this->set_error(sprintf(_("User '%s' does not exist"), 
                                            $alias));

         // Create query
         $query = sprintf("UPDATE %s SET nickname='%s', firstname='%s', ".
                          "lastname='%s', email='%s', label='%s' ".
                          "WHERE owner='%s' AND nickname='%s'",
                          $this->table, 
                          $this->dbh->quoteString($userdata["nickname"]),
                          $this->dbh->quoteString($userdata["firstname"]), 
                          $this->dbh->quoteString($userdata["lastname"]),
                          $this->dbh->quoteString($userdata["email"]), 
                          $this->dbh->quoteString($userdata["label"]),
                          $this->owner,
                          $this->dbh->quoteString($alias) );

         // Do the insert
         $r = $this->dbh->simpleQuery($query);
         if($r == DB_OK) return true;

         // Fail
         return $this->set_error(sprintf(_("Database error: %s"),
                                         DB::errorMessage($r)));
      }
   } // End of class abook_database

} ?>