<?PHP 
//////////////////////////////////////////////////////////////////////////
// + $Id$
// +------------------------------------------------------------------+ //
// + Cake <http://sputnik.pl/cake>                                    + //
// + Copyright: (c) 2005 Michal Tatarynowicz                          + //
// +                                                                  + //
// + Author(s): (c) 2005 Michal Tatarynowicz <tatarynowicz@gmail.com> + //
// +                                                                  + //
// +------------------------------------------------------------------+ //
// + Licensed under the Public Domain Licence                         + //
// +------------------------------------------------------------------+ //
//////////////////////////////////////////////////////////////////////////

/**
  * Purpose: Model
  * DBO-backed object data model, loosly based on RoR (www.rubyonrails.com).
  * Automatically selects db table name based on pluralized lowercase object class name
  * (i.e. class 'User' => table 'users'; class 'Man' => table 'men')
  * The table is required to have at least 'id auto_increment', 'created datetime', 
  * and 'modified datetime' fields
  *
  * To do:
  *   - schema-related cross-table ($has_one, $has_many, $belongs_to)
  *
  * @filesource 
  * @modifiedby $LastChangedBy$  
  * @lastmodified $Date$
  * @author Michal Tatarynowicz <tatarynowicz@gmail.com>
  * @copyright Copyright (c) 2005, Michal Tatarynowicz <tatarynowicz@gmail.com>
  * @package cake
  * @subpackage cake.libs
  * @since Cake v 0.2.9
  * @version $Revision$
  * @license Public_Domain
  *
  */

/**
  * Enter description here...
  *
  */
uses('object', 'validators', 'inflector');

/**
  * Enter description here...
  *
  *
  * @package cake
  * @subpackage cake.libs
  * @since Cake v 0.2.9
  *
  */
class Model extends Object {
    
/**
  * Enter description here...
  *
  * @var unknown_type
  * @access public
  */
    var $parent = false;

/**
  * Enter description here...
  *
  * @var unknown_type
  * @access public
  */
    var $use_table = false;

/**
  * Enter description here...
  *
  * @var unknown_type
  * @access public
  */
    var $id = false;

/**
  * Enter description here...
  *
  * @var unknown_type
  * @access public
  */
    var $data = array();
    // protected
/**
  * Enter description here...
  *
  * @var unknown_type
  * @access public
  */
    var $table = false;
    // private
/**
  * Enter description here...
  *
  * @var unknown_type
  * @access private
  */
    var $_table_info = null;

/**
  * Enter description here...
  *
  * @var unknown_type
  * @access private
  */
    var $_one_to_many = array();

/**
  * Enter description here...
  *
  * @var unknown_type
  * @access private
  */
    var $_one_to_one = array();

/**
  * Enter description here...
  *
  * @var unknown_type
  * @access private
  */
    var $_has_multiple = array();

/**
  * Enter description here...
  *
  * append entries for validation as ('field_name' => '/^perl_compat_regexp$/') that has to match with preg_match()
  * validate with Model::validate()
  * @var unknown_type
  */
    var $validate = array();

/**
  * Enter description here...
  *
  * @param unknown_type $id
  */
    function __construct ($id=false) {
        global $DB;

        $this->db = &$DB;

        if ($id)
        $this->id = $id;

        $table_name = $this->use_table? $this->use_table: Inflector::tableize(get_class($this));
        $this->use_table ($table_name);
        parent::__construct();

        $this->create_links();
    }

/**
  * Enter description here...
  *
  */
    function create_links () {
        if (!empty($this->has_many))
        $this->_has_multiple = explode(',', $this->has_many);

        foreach ($this->_has_multiple as $model_name) {
            // todo fix strip the model name
            $model_name = Inflector::singularize($model_name);
            $this->$model_name = new $model_name();
        }

        $this->relink();
    }

/**
  * Enter description here...
  *
  */
    function relink () {
        foreach ($this->_has_multiple as $model) {
            $name = Inflector::singularize($model);
            $this->$name->clear_links();
            $this->$name->link_many_to_one(get_class($this), $this->id);
        }
    }

/**
  * Enter description here...
  *
  * @param unknown_type $model_name
  * @param unknown_type $value
  */
    function link_many_to_one ($model_name, $value=null) {
        $table_name = Inflector::tableize($model_name);
        $field_name = Inflector::singularize($table_name).'_id';
        $this->_one_to_many[] = array($table_name, $field_name, $value);
    }

/**
  * Enter description here...
  *
  */
    function clear_links () {
        $this->_one_to_many = array();
    }

/**
  * Enter description here...
  *
  * @param unknown_type $table_name
  */
    function use_table ($table_name) {
        if (!in_array($table_name, $this->db->tables()))
        trigger_error (sprintf(ERROR_NO_MODEL_TABLE, get_class($this), $table_name), E_USER_ERROR);
        else {
            $this->table = $table_name;
            $this->load_info();
        }
    }

/**
  * Enter description here...
  *
  * @param unknown_type $one
  * @param unknown_type $two
  * @return unknown
  */
    function set ($one, $two=null) {
        $data = is_array($one)? $one: array($one=>$two);

        foreach ($data as $n => $v) {
            if (!$this->has_field($n)) {
                DEBUG?
                trigger_error(sprintf(ERROR_NO_FIELD_IN_MODEL_DB, $n, $this->table), E_USER_ERROR):
                trigger_error('Application error occured, trying to set a field name that doesn\'t exist.', E_USER_WARNING);
            }

            $n == 'id'? $this->id = $v: $this->data[$n] = $v;
        }

        return $data;
    }

/**
  * Enter description here...
  *
  * @param unknown_type $id
  */
    function set_id ($id) {
        $this->id = $id;
        $this->relink();
    }

/**
  * Enter description here...
  *
  */
    function load_info () {
        if (empty($this->_table_info))
        $this->_table_info = new neatArray($this->db->fields($this->table));
    }

/**
  * Enter description here...
  *
  * @param unknown_type $name
  * @return unknown
  */
    function has_field ($name) {
        return $this->_table_info->find_in('Field', $name);
    }


    // returns data from db
    // requires $this->id
    // expects coma-separated field list, array of field names, or empty for all fields
/**
  * Enter description here...
  *
  * @param unknown_type $fields
  * @return unknown
  */
    function read ($fields=null) {
        return $this->id? $this->find("id = '{$this->id}'", $fields): false;
    }

    // returns a field value from db
    // requires $this->id
    // requires a field name
/**
  * Enter description here...
  *
  * @param unknown_type $name
  * @return unknown
  */
    function field ($name) {
        if (isset($this->data[$name]))
        return $this->data[$name];
        else {
            if ($this->id && $data = $this->read($name)) {
                return isset($data[$name])? $data[$name]: false;
            }
            else {
                return false;
            }
        }
    }

    // saves $this->data to db
    // if $this->id is set, updates a record, else inserts a records
/**
  * Enter description here...
  *
  * @param unknown_type $data
  * @return unknown
  */
    function save ($data=null) {
        if ($data) $this->set($data);

        if (!$this->validates())
        return false;

        $lines = array();
        foreach ($this->data as $n => $v)
        $lines[] = "{$n} = '{$v}'";

        // finds if 'created' and 'updated' fields exists and generates sql to handle them
        $update_sql = array();
        if ($this->has_field('created') && !$this->id) $update_sql[] = 'created = NOW()';
        if ($this->has_field('modified')) $update_sql[] = 'modified = NOW()';
        $update_sql = count($update_sql)? ', '.join(', ', $update_sql): null;

        if (count($lines)) {

            if ($this->id) {
                if ($this->db->q("UPDATE {$this->table} SET ".join(', ', $lines)."{$update_sql} WHERE id = '{$this->id}'")
                && $this->db->last_affected()) {
                    $this->data = false;
                    return true;
                }
                else
                return $this->db->has_any($this->table, "id = '{$this->id}'");
            }
            else {
                if ($this->db->q("INSERT INTO {$this->table} SET ".join(', ', $lines).$update_sql)) {
                    $this->id = $this->db->last_insert_id();
                    return true;
                }
                else {
                    return false;
                }
            }
        }
        else {
            return false;
        }
    }

    // deletes a record from db
    // requires $this->id
/**
  * Enter description here...
  *
  * @param unknown_type $id
  * @return unknown
  */
    function remove ($id=null) {
        return $this->del($id);
    }

/**
  * Enter description here...
  *
  * @param unknown_type $id
  * @return unknown
  */
    function del ($id=null) {
        if ($id) $this->id = $id;
        if ($this->id && $this->db->q("DELETE FROM {$this->table} WHERE id = '{$this->id}'")) {
            $this->id = false;
            return true;
        }
        else
        return false;
    }

    // returns true if record exists in db
    // requires $this->id
/**
  * Enter description here...
  *
  * @return unknown
  */
    function exists () {
        return $this->id? $this->db->has_any($this->table, "id = '{$this->id}'"): false;
    }

    // returns a row if found, or otherwise null
    // expects sql conditions, or empty for no conditions
    // expects coma-separated fields list, array of field names, or empty for all fields
/**
  * Enter description here...
  *
  * @param unknown_type $conditions
  * @param unknown_type $fields
  * @return unknown
  */
    function find ($conditions = null, $fields = null) {
        $data = $this->find_all($conditions, $fields, null, 1);
        return empty($data[0])? false: $data[0];
    }

    // returns specified fields from db records matching conditions
    // expects sql conditions, or empty for no conditions
    // expects coma-separated fields list, array of field names, or empty for all fields
    // expects sql order, or empty for default order
    // expects limit, or empty for no limit
    // expects page number for offset, or empty for no offset
/**
  * Enter description here...
  *
  * @param unknown_type $conditions
  * @param unknown_type $fields
  * @param unknown_type $order
  * @param unknown_type $limit
  * @param unknown_type $page
  * @return unknown
  */
    function find_all ($conditions = null, $fields = null, $order = null, $limit = null, $page = null) {
        if (is_array($fields))
        $f = $fields;
        elseif ($fields)
        $f = array($fields);
        else
        $f = array('*');

        $joins = $whers = array();

        foreach ($this->_one_to_many as $rule) {
            list($table, $field, $value) = $rule;
            $joins[] = "LEFT JOIN {$table} ON {$this->table}.{$field} = {$table}.id";
            $whers[] = "{$this->table}.{$field} = '{$value}'";
        }

        $joins = count($joins)? join(' ', $joins): null;
        $whers = count($whers)? '('.join(' AND ', $whers).')': null;
        $conditions .= ($conditions && $whers? ' AND ': null).$whers;

        $data = $this->db->all(
        "SELECT "
        .join(', ', $f)
        ." FROM {$this->table} {$joins}"
        .($conditions? " WHERE {$conditions}":null)
        .($order? " ORDER BY {$order}": null)
        .($limit? " LIMIT ".($page>0? $limit*($page-1): '0').",{$limit}": null), false, MYSQL_ASSOC);

        return $data;
    }

/**
  * Enter description here...
  *
  * @param unknown_type $sql
  * @param unknown_type $debug
  * @return unknown
  */
    function find_by_sql ($sql, $debug=0) {
        return $this->db->all($sql, $debug);
    }

/**
  * Enter description here...
  *
  * @param unknown_type $conditions
  * @param unknown_type $fields
  * @return unknown
  */
    function find_all_threaded ($conditions=null, $fields=null) {
        return $this->_do_thread($this->find_all($conditions, $fields), null);
    }

/**
  * Enter description here...
  *
  * @param unknown_type $conditions
  * @return unknown
  */
    function find_count ($conditions) {
        list($data) = $this->find_all($conditions, 'COUNT(id) AS count');
        return $data['count'];
    }

/**
  * Enter description here...
  *
  * @param unknown_type $data
  * @param unknown_type $root
  * @return unknown
  */
    function _do_thread ($data, $root) {
        $out = array();

        for ($ii=0; $ii<sizeof($data); $ii++) {
            if ($data[$ii]['parent_id'] == $root) {
                $tmp = $data[$ii];
                $tmp['children'] = isset($data[$ii]['id'])? $this->_do_thread($data, $data[$ii]['id']): null;
                $out[] = $tmp;
            }
        }

        return $out;
    }

/**
  * Enter description here...
  *
  * @param unknown_type $conditions
  * @param unknown_type $field
  * @param unknown_type $value
  * @return unknown
  */
    function find_neighbours ($conditions, $field, $value) {
        list($prev) = $this->find_all($conditions." AND {$field} < '{$value}'", $field, "{$field} DESC", 1);
        list($next) = $this->find_all($conditions." AND {$field} > '{$value}'", $field, "{$field} ASC", 1);

        return array('prev'=>$prev['id'], 'next'=>$next['id']);
    }

/**
  * Enter description here...
  *
  * @param unknown_type $sql
  * @return unknown
  */
    function query ($sql) {
        return $this->db->q($sql);
    }

/**
  * Enter description here...
  *
  * @param unknown_type $data
  * @return unknown
  */
    function validates ($data=null) {
        $errors = count($this->invalid_fields($data));

        return $errors == 0;
    }

/**
  * Enter description here...
  *
  * @param unknown_type $data
  * @return unknown
  */
    function invalid_fields ($data=null) {
        return $this->_invalid_fields($data);
    }

/**
  * Enter description here...
  *
  * @param unknown_type $data
  * @return unknown
  */
    function _invalid_fields ($data=null) {
        if (!isset($this->validate))
        return true;

        $data = ($data? $data: (isset($this->data)? $this->data: array()));
        $errors = array();

        foreach ($this->validate as $field_name=>$validator) {
            if (isset($data[$field_name])) {
                if (!preg_match($validator, $data[$field_name]))
                $errors[$field_name] = 1;
            }
        }

        return $errors;
    }

}

?>