<?php
// +----------------------------------------------------------------------+
// | PHP versions 4 and 5                                                 |
// +----------------------------------------------------------------------+
// | Copyright (c) 1998-2007 Manuel Lemos, Tomas V.V.Cox,                 |
// | Stig. S. Bakken, Lukas Smith                                         |
// | All rights reserved.                                                 |
// +----------------------------------------------------------------------+
// | MDB2 is a merge of PEAR DB and Metabases that provides a unified DB  |
// | API as well as database abstraction for PHP applications.            |
// | This LICENSE is in the BSD license style.                            |
// |                                                                      |
// | Redistribution and use in source and binary forms, with or without   |
// | modification, are permitted provided that the following conditions   |
// | are met:                                                             |
// |                                                                      |
// | Redistributions of source code must retain the above copyright       |
// | notice, this list of conditions and the following disclaimer.        |
// |                                                                      |
// | Redistributions in binary form must reproduce the above copyright    |
// | notice, this list of conditions and the following disclaimer in the  |
// | documentation and/or other materials provided with the distribution. |
// |                                                                      |
// | Neither the name of Manuel Lemos, Tomas V.V.Cox, Stig. S. Bakken,    |
// | Lukas Smith nor the names of his contributors may be used to endorse |
// | or promote products derived from this software without specific prior|
// | written permission.                                                  |
// |                                                                      |
// | THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS  |
// | "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT    |
// | LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS    |
// | FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE      |
// | REGENTS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,          |
// | INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, |
// | BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS|
// |  OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED  |
// | AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT          |
// | LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY|
// | WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE          |
// | POSSIBILITY OF SUCH DAMAGE.                                          |
// +----------------------------------------------------------------------+
// | Authors: Paul Cooper <pgc@ucecom.com>                                |
// |          Lorenzo Alberton <l.alberton@quipo.it>                      |
// +----------------------------------------------------------------------+
//
// $Id$

require_once 'MDB2/Driver/Reverse/Common.php';

/**
 * MDB2 PostGreSQL driver for the schema reverse engineering module
 *
 * @package MDB2
 * @category Database
 * @author  Paul Cooper <pgc@ucecom.com>
 */
class MDB2_Driver_Reverse_pgsql extends MDB2_Driver_Reverse_Common
{
    // {{{ getTableFieldDefinition()

    /**
     * Get the structure of a field into an array
     *
     * @param string    $table       name of table that should be used in method
     * @param string    $field_name  name of field that should be used in method
     * @return mixed data array on success, a MDB2 error on failure
     * @access public
     */
    function getTableFieldDefinition($table, $field_name)
    {
        $db =& $this->getDBInstance();
        if (PEAR::isError($db)) {
            return $db;
        }

        $result = $db->loadModule('Datatype', null, true);
        if (PEAR::isError($result)) {
            return $result;
        }

        $query = "SELECT a.attname AS name,
                         t.typname AS type,
                         CASE a.attlen
                           WHEN -1 THEN
	                         CASE t.typname
	                           WHEN 'numeric' THEN (a.atttypmod / 65536)
	                           WHEN 'decimal' THEN (a.atttypmod / 65536)
	                           WHEN 'money'   THEN (a.atttypmod / 65536)
	                           ELSE CASE a.atttypmod
                                 WHEN -1 THEN NULL
	                             ELSE a.atttypmod - 4
	                           END
                             END
	                       ELSE a.attlen
                         END AS length,
	                     CASE t.typname
	                       WHEN 'numeric' THEN (a.atttypmod % 65536) - 4
	                       WHEN 'decimal' THEN (a.atttypmod % 65536) - 4
	                       WHEN 'money'   THEN (a.atttypmod % 65536) - 4
	                       ELSE 0
                         END AS scale,
                         a.attnotnull,
                         a.atttypmod,
                         a.atthasdef,
                         (SELECT substring(pg_get_expr(d.adbin, d.adrelid) for 128)
                            FROM pg_attrdef d
                           WHERE d.adrelid = a.attrelid
                             AND d.adnum = a.attnum
                             AND a.atthasdef
                         ) as default
                    FROM pg_attribute a,
                         pg_class c,
                         pg_type t
                   WHERE c.relname = ".$db->quote($table, 'text')."
                     AND a.atttypid = t.oid
                     AND c.oid = a.attrelid
                     AND NOT a.attisdropped
                     AND a.attnum > 0
                     AND a.attname = ".$db->quote($field_name, 'text')."
                ORDER BY a.attnum";
        $column = $db->queryRow($query, null, MDB2_FETCHMODE_ASSOC);
        if (PEAR::isError($column)) {
            return $column;
        }

        if (empty($column)) {
            return $db->raiseError(MDB2_ERROR_NOT_FOUND, null, null,
                'it was not specified an existing table column', __FUNCTION__);
        }

        $column = array_change_key_case($column, CASE_LOWER);
        $mapped_datatype = $db->datatype->mapNativeDatatype($column);
        if (PEAR::IsError($mapped_datatype)) {
            return $mapped_datatype;
        }
        list($types, $length, $unsigned, $fixed) = $mapped_datatype;
        $notnull = false;
        if (!empty($column['attnotnull']) && $column['attnotnull'] == 't') {
            $notnull = true;
        }
        $default = null;
        if ($column['atthasdef'] === 't'
            && !preg_match("/nextval\('([^']+)'/", $column['default'])
        ) {
            $default = $column['default'];#substr($column['adsrc'], 1, -1);
            if (is_null($default) && $notnull) {
                $default = '';
            }
        }
        $autoincrement = false;
        if (preg_match("/nextval\('([^']+)'/", $column['default'], $nextvals)) {
            $autoincrement = true;
        }
        $definition[0] = array('notnull' => $notnull, 'nativetype' => $column['type']);
        if (!is_null($length)) {
            $definition[0]['length'] = $length;
        }
        if (!is_null($unsigned)) {
            $definition[0]['unsigned'] = $unsigned;
        }
        if (!is_null($fixed)) {
            $definition[0]['fixed'] = $fixed;
        }
        if ($default !== false) {
            $definition[0]['default'] = $default;
        }
        if ($autoincrement !== false) {
            $definition[0]['autoincrement'] = $autoincrement;
        }
        foreach ($types as $key => $type) {
            $definition[$key] = $definition[0];
            if ($type == 'clob' || $type == 'blob') {
                unset($definition[$key]['default']);
            }
            $definition[$key]['type'] = $type;
            $definition[$key]['mdb2type'] = $type;
        }
        return $definition;
    }

    // }}}
    // {{{ getTableIndexDefinition()
    /**
     * Get the structure of an index into an array
     *
     * @param string    $table      name of table that should be used in method
     * @param string    $index_name name of index that should be used in method
     * @return mixed data array on success, a MDB2 error on failure
     * @access public
     */
    function getTableIndexDefinition($table, $index_name)
    {
        $db =& $this->getDBInstance();
        if (PEAR::isError($db)) {
            return $db;
        }

        $query = 'SELECT relname, indkey FROM pg_index, pg_class';
        $query.= ' WHERE pg_class.oid = pg_index.indexrelid';
        $query.= " AND indisunique != 't' AND indisprimary != 't'";
        $query.= ' AND pg_class.relname = %s';
        $index_name_mdb2 = $db->getIndexName($index_name);
        $row = $db->queryRow(sprintf($query, $db->quote($index_name_mdb2, 'text')), null, MDB2_FETCHMODE_ASSOC);
        if (PEAR::isError($row) || empty($row)) {
            // fallback to the given $index_name, without transformation
            $row = $db->queryRow(sprintf($query, $db->quote($index_name, 'text')), null, MDB2_FETCHMODE_ASSOC);
        }
        if (PEAR::isError($row)) {
            return $row;
        }

        if (empty($row)) {
            return $db->raiseError(MDB2_ERROR_NOT_FOUND, null, null,
                'it was not specified an existing table index', __FUNCTION__);
        }

        $row = array_change_key_case($row, CASE_LOWER);

        $db->loadModule('Manager', null, true);
        $columns = $db->manager->listTableFields($table);

        $definition = array();

        $index_column_numbers = explode(' ', $row['indkey']);

        $colpos = 1;
        foreach ($index_column_numbers as $number) {
            $definition['fields'][$columns[($number - 1)]] = array(
                'position' => $colpos++,
                'sorting' => 'ascending',
            );
        }
        return $definition;
    }

    // }}}
    // {{{ getTableConstraintDefinition()
    /**
     * Get the structure of a constraint into an array
     *
     * @param string    $table      name of table that should be used in method
     * @param string    $constraint_name name of constraint that should be used in method
     * @return mixed data array on success, a MDB2 error on failure
     * @access public
     */
    function getTableConstraintDefinition($table, $constraint_name)
    {
        $db =& $this->getDBInstance();
        if (PEAR::isError($db)) {
            return $db;
        }
        
        $query = 'SELECT relname, indisunique, indisprimary, indkey FROM pg_index, pg_class';
        $query.= ' WHERE pg_class.oid = pg_index.indexrelid';
        $query.= " AND (indisunique = 't' OR indisprimary = 't')";
        $query.= ' AND pg_class.relname = %s';
        $constraint_name_mdb2 = $db->getIndexName($constraint_name);
        $row = $db->queryRow(sprintf($query, $db->quote($constraint_name_mdb2, 'text')), null, MDB2_FETCHMODE_ASSOC);
        if (PEAR::isError($row) || empty($row)) {
            // fallback to the given $index_name, without transformation
            $row = $db->queryRow(sprintf($query, $db->quote($constraint_name, 'text')), null, MDB2_FETCHMODE_ASSOC);
        }
        if (PEAR::isError($row)) {
            return $row;
        }

        if (empty($row)) {
            return $db->raiseError(MDB2_ERROR_NOT_FOUND, null, null,
                $constraint_name . ' is not an existing table constraint', __FUNCTION__);
        }

        $row = array_change_key_case($row, CASE_LOWER);

        $db->loadModule('Manager', null, true);
        $columns = $db->manager->listTableFields($table);

        $definition = array();
        if ($row['indisprimary'] == 't') {
            $definition['primary'] = true;
        } elseif ($row['indisunique'] == 't') {
            $definition['unique'] = true;
        }

        $index_column_numbers = explode(' ', $row['indkey']);

        $colpos = 1;
        foreach ($index_column_numbers as $number) {
            $definition['fields'][$columns[($number - 1)]] = array(
                'position' => $colpos++,
                'sorting' => 'ascending',
            );
        }
        return $definition;
    }

    // }}}
    // {{{ getTriggerDefinition()

    /**
     * Get the structure of a trigger into an array
     *
     * EXPERIMENTAL
     *
     * WARNING: this function is experimental and may change the returned value
     * at any time until labelled as non-experimental
     *
     * @param string    $trigger    name of trigger that should be used in method
     * @return mixed data array on success, a MDB2 error on failure
     * @access public
     *
     * @TODO: add support for plsql functions and functions with args
     */
    function getTriggerDefinition($trigger)
    {
        $db =& $this->getDBInstance();
        if (PEAR::isError($db)) {
            return $db;
        }

        $query = "SELECT trg.tgname AS trigger_name,
                         tbl.relname AS table_name,
                         CASE
                            WHEN p.proname IS NOT NULL THEN 'EXECUTE PROCEDURE ' || p.proname || '();'
                            ELSE ''
                         END AS trigger_body,
                         CASE trg.tgtype & cast(2 as int2)
                            WHEN 0 THEN 'AFTER'
                            ELSE 'BEFORE'
                         END AS trigger_type,
                         CASE trg.tgtype & cast(28 as int2)
                            WHEN 16 THEN 'UPDATE'
                            WHEN 8 THEN 'DELETE'
                            WHEN 4 THEN 'INSERT'
                            WHEN 20 THEN 'INSERT, UPDATE'
                            WHEN 28 THEN 'INSERT, UPDATE, DELETE'
                            WHEN 24 THEN 'UPDATE, DELETE'
                            WHEN 12 THEN 'INSERT, DELETE'
                         END AS trigger_event,
                         trg.tgenabled AS trigger_enabled,
                         obj_description(trg.oid, 'pg_trigger') AS trigger_comment
                    FROM pg_trigger trg,
                         pg_class tbl,
                         pg_proc p
                   WHERE trg.tgrelid = tbl.oid
                     AND trg.tgfoid = p.oid
                     AND trg.tgname = ". $db->quote($trigger, 'text');
        $types = array(
            'trigger_name'    => 'text',
            'table_name'      => 'text',
            'trigger_body'    => 'text',
            'trigger_type'    => 'text',
            'trigger_event'   => 'text',
            'trigger_comment' => 'text',
            'trigger_enabled' => 'boolean',
        );
        return $db->queryRow($query, $types, MDB2_FETCHMODE_ASSOC);
    }
    
    // }}}
    // {{{ tableInfo()

    /**
     * Returns information about a table or a result set
     *
     * NOTE: only supports 'table' and 'flags' if <var>$result</var>
     * is a table name.
     *
     * @param object|string  $result  MDB2_result object from a query or a
     *                                 string containing the name of a table.
     *                                 While this also accepts a query result
     *                                 resource identifier, this behavior is
     *                                 deprecated.
     * @param int            $mode    a valid tableInfo mode
     *
     * @return array  an associative array with the information requested.
     *                 A MDB2_Error object on failure.
     *
     * @see MDB2_Driver_Common::tableInfo()
     */
    function tableInfo($result, $mode = null)
    {
        if (is_string($result)) {
           return parent::tableInfo($result, $mode);
        }

        $db =& $this->getDBInstance();
        if (PEAR::isError($db)) {
            return $db;
        }

        $resource = MDB2::isResultCommon($result) ? $result->getResource() : $result;
        if (!is_resource($resource)) {
            return $db->raiseError(MDB2_ERROR_NEED_MORE_DATA, null, null,
                'Could not generate result resource', __FUNCTION__);
        }

        if ($db->options['portability'] & MDB2_PORTABILITY_FIX_CASE) {
            if ($db->options['field_case'] == CASE_LOWER) {
                $case_func = 'strtolower';
            } else {
                $case_func = 'strtoupper';
            }
        } else {
            $case_func = 'strval';
        }

        $count = @pg_num_fields($resource);
        $res   = array();

        if ($mode) {
            $res['num_fields'] = $count;
        }

        $db->loadModule('Datatype', null, true);
        for ($i = 0; $i < $count; $i++) {
            $res[$i] = array(
                'table' => function_exists('pg_field_table') ? @pg_field_table($resource, $i) : '',
                'name'  => $case_func(@pg_field_name($resource, $i)),
                'type'  => @pg_field_type($resource, $i),
                'length' => @pg_field_size($resource, $i),
                'flags' => '',
            );
            $mdb2type_info = $db->datatype->mapNativeDatatype($res[$i]);
            if (PEAR::isError($mdb2type_info)) {
               return $mdb2type_info;
            }
            $res[$i]['mdb2type'] = $mdb2type_info[0][0];
            if ($mode & MDB2_TABLEINFO_ORDER) {
                $res['order'][$res[$i]['name']] = $i;
            }
            if ($mode & MDB2_TABLEINFO_ORDERTABLE) {
                $res['ordertable'][$res[$i]['table']][$res[$i]['name']] = $i;
            }
        }

        return $res;
    }
}
?>