<?php
class DoubleEntry extends AppModel {

	var $belongsTo = array(
		'DebitEntry' => array(
			'className' => 'LedgerEntry',
		),
		'CreditEntry' => array(
			'className' => 'LedgerEntry',
		),
	);


  /**************************************************************************
   **************************************************************************
   **************************************************************************
   * function: verifyDoubleEntry
   *  - Verifies consistenty of new double entry data
   *    (not in a pre-existing double entry)
   */
  function verifyDoubleEntry($entry1, $entry2, $entry1_tender = null) {
/*     pr(array("DoubleEntry::verifyDoubleEntry()" */
/* 	     => compact('entry1', 'entry2', 'entry1_tender'))); */

    $LE = new LedgerEntry();
    if (!$LE->verifyLedgerEntry($entry1, $entry1_tender)) {
/*       pr(array("DoubleEntry::verifyDoubleEntry()" */
/* 	       => "Entry1 verification failed")); */
      return false;
    }
    if (!$LE->verifyLedgerEntry($entry2)) {
/*       pr(array("DoubleEntry::verifyDoubleEntry()" */
/* 	       => "Entry2 verification failed")); */
      return false;
    }

    if (!(($entry1['crdr'] === 'DEBIT' && $entry2['crdr'] === 'CREDIT') ||
	  ($entry1['crdr'] === 'CREDIT' && $entry2['crdr'] === 'DEBIT')) ||
	($entry1['amount'] != $entry2['amount'])) {
/*       pr(array("DoubleEntry::verifyDoubleEntry()" */
/* 	       => "Double Entry verification failed")); */
      return false;
    }

    return true;
  }

  /**************************************************************************
   **************************************************************************
   **************************************************************************
   * function: addDoubleEntry
   *  - Inserts new Double Entry into the database
   */

  function addDoubleEntry($entry1, $entry2, $entry1_tender = null) {
    //$this->prFunctionLevel(16);
    $this->prEnter(compact('entry1', 'entry2', 'entry1_tender'));

    $ret = array();
    if (!$this->verifyDoubleEntry($entry1, $entry2, $entry1_tender))
      return $this->prReturn(array('error' => true) + $ret);

    // Handle the case where a double entry involves the same
    // exact ledger.  This would not serve any useful purpose.
    // It is not, however, an error.  It is semantically correct
    // just not really logically correct.  To make this easier,
    // just ensure ledger_id is set for each entry, even though
    // it would be handled later by the LedgerEntry model.
    //array($entry1, $entry2) AS &$entry) {
    for ($i=1; $i <= 2; ++$i) {
      if (empty(${'entry'.$i}['ledger_id']))
	${'entry'.$i}['ledger_id'] =
	  $this->DebitEntry->Account->currentLedgerID(${'entry'.$i}['account_id']);
    }
    if ($entry1['ledger_id'] == $entry2['ledger_id'])
      return $this->prReturn(array('error' => false));

    // Since this model only relates to DebitEntry and CreditEntry...
    $LE = new LedgerEntry();

    // Add the first ledger entry to the database
    $result = $LE->addLedgerEntry($entry1, $entry1_tender);
    $ret['Entry1'] = $result;
    if ($result['error'])
      return $this->prReturn(array('error' => true) + $ret);
    
    // Add the second ledger entry to the database
    $result = $LE->addLedgerEntry($entry2);
    $ret['Entry2'] = $result;
    if ($result['error'])
      return $this->prReturn(array('error' => true) + $ret);

    // Now link them as a double entry
    $double_entry = array();
    $double_entry['debit_entry_id'] = 
      ($entry1['crdr'] === 'DEBIT') ? $ret['Entry1']['ledger_entry_id'] : $ret['Entry2']['ledger_entry_id'];
    $double_entry['credit_entry_id'] = 
      ($entry1['crdr'] === 'CREDIT') ? $ret['Entry1']['ledger_entry_id'] : $ret['Entry2']['ledger_entry_id'];

    $ret['data'] = $double_entry;

    $this->create();
    if (!$this->save($double_entry))
      return $this->prReturn(array('error' => true) + $ret);

    $ret['double_entry_id'] = $this->id;
    return $this->prReturn($ret + array('error' => false));
  }
}