<?php
class LedgerEntry extends AppModel {

	var $belongsTo = array(
		'Transaction',
		'Account',
		'Ledger',
	);

	var $hasOne = array(
		'Tender',
	);

	var $hasMany = array(
	);

	var $hasAndBelongsToMany = array(
		// The Debit half of the double entry matching THIS Credit (if it is one)
		'DebitEntry' => array(
			'className' => 'LedgerEntry',
			'joinTable' => 'double_entries',
			'linkalias' => 'DDE',
			'foreignKey' => 'credit_entry_id',
			'associationForeignKey' => 'debit_entry_id',
		),

		// The Credit half of the double entry matching THIS Debit (if it is one)
		'CreditEntry' => array(
			'className' => 'LedgerEntry',
			'joinTable' => 'double_entries',
			'linkalias' => 'CDE',
			'foreignKey' => 'debit_entry_id',
			'associationForeignKey' => 'credit_entry_id',
		),
	);


  /**************************************************************************
   **************************************************************************
   **************************************************************************
   * function: debitCreditFields
   *  - Returns the fields necessary to determine whether the queried
   *    entries are a debit, or a credit, and also the effect each have
   *    on the overall balance of the account/ledger.
   */

  function debitCreditFields($sum = false, $balance = true,
			     $entry_name = 'LedgerEntry', $account_name = 'Account') {
    $fields = array
      (
       ($sum ? 'SUM(' : '') .
       "IF({$entry_name}.crdr = 'DEBIT'," .
       "   {$entry_name}.amount, NULL)" .
       ($sum ? ')' : '') . ' AS debit' . ($sum ? 's' : ''),

       ($sum ? 'SUM(' : '') .
       "IF({$entry_name}.crdr = 'CREDIT'," .
       "   {$entry_name}.amount, NULL)" .
       ($sum ? ')' : '') . ' AS credit' . ($sum ? 's' : ''),
       );

    if ($balance)
      $fields[] = 
	($sum ? 'SUM(' : '') .
	"IF(${account_name}.type IN ('ASSET', 'EXPENSE')," .
	"   IF({$entry_name}.crdr = 'DEBIT',  1, -1)," .
	"   IF({$entry_name}.crdr = 'CREDIT', 1, -1))" .
	" * IF({$entry_name}.amount, {$entry_name}.amount, 0)" .
	($sum ? ')' : '') . ' AS balance';

    if ($sum)
      $fields[] = "COUNT({$entry_name}.id) AS entries";

    return $fields;
  }


  /**************************************************************************
   **************************************************************************
   **************************************************************************
   * function: addCharge
   *  - Adds a new charge
   */

  function addCharge($data, $transaction, $customer_id, $lease_id = null) {
    // Create some models for convenience
    $A = new Account();

    // Assume this will succeed
    $ret = true;

    // Establish the key charge parameters
    $charge = array_intersect_key($data, array('stamp'=>1, 'amount'=>1, 'account_id'=>1));
					       
    $charge['customer_id'] = $customer_id;
    $charge['lease_id'] = $lease_id;
    $charge['type'] = 'CHARGE';

    $ids = $this->Entry->Ledger->Account->postLedgerEntry
      ($transaction,
       $charge,
       array('debit_ledger_id' => $A->currentLedgerID($data['account_id']),
	     'credit_ledger_id' => $A->currentLedgerID($A->accountReceivableAccountID())
	     ) + $data
       );
    
    if ($ids['error'])
      $ret = false;

    return $ids['charge_id'];
  }


  /**************************************************************************
   **************************************************************************
   **************************************************************************
   * function: addPayment
   *  - Adds a new payment
   */

  function addPayment($data, $transaction, $customer_id, $lease_id = null) {
    // Create some models for convenience
    $A = new Account();

    // Assume this will succeed
    $ret = true;

    // Establish the key payment parameters
    $payment = array_intersect_key($data, array('stamp'=>1, 'name'=>1, 'monetary_type'=>1,
						'data1'=>1, 'data2'=>1, 'data3'=>1, 'data4'=>1,
						'amount'=>1, 'account_id'=>1));
    $payment['customer_id'] = $customer_id;
    $payment['type'] = 'PAYMENT';

    $ids = $this->Entry->Ledger->Account->postLedgerEntry
      ($transaction,
       $payment,
       array('debit_ledger_id' => $A->currentLedgerID($data['account_id']),
	     'credit_ledger_id' => $A->currentLedgerID($A->accountReceivableAccountID())
	     ) + $data
       );
    
    if ($ids['error'])
      $ret = false;

    return $ids['payment_id'];
  }


  /**************************************************************************
   **************************************************************************
   **************************************************************************
   * function: reverse
   *  - Reverses the charges
   *
   * SAMPLE MOVE IN w/ PRE PAYMENT
   * DEPOSIT   RENT      A/R    RECEIPT   CHECK    PETTY    BANK
   * -------  -------  -------  -------  -------  -------  -------
   *    |25      |      25|        |        |        |        |    
   *    |        |20    20|        |        |        |        |    
   *    |        |20    20|        |        |        |        |    
   *    |        |20    20|        |        |        |        |    
   *    |        |        |25    25|        |        |        |     
   *    |        |        |20    20|        |        |        |     
   *    |        |        |20    20|        |        |        |     
   *    |        |        |20    20|        |        |        |     
   *    |        |        |        |85    85|        |        |     
   *    |        |        |        |        |85      |      85|     

   * MOVE OUT and REFUND FINAL MONTH
   * DEPOSIT   RENT      C/P    RECEIPT   CHECK    PETTY    BANK
   * -------  -------  -------  -------  -------  -------  -------
   *  25|        |        |25      |        |        |        |    t20   e20a
   *    |      20|        |20      |        |        |        |    t20   e20b

   * -ONE REFUND CHECK-
   *    |        |      25|        |25      |        |        |    t30   e30a
   *    |        |      20|        |20      |        |        |    t30   e30b
   *    |        |        |      45|        |        |        |45  t40   e40
   * -OR MULTIPLE-
   *    |        |      15|        |15      |        |        |    t50a  e50a
   *    |        |        |      15|        |        |15      |    t60a  e60a
   *    |        |      30|        |30      |        |        |    t50b  e50b
   *    |        |        |      30|        |        |        |30  t60b  e60b
   *    |        |        |        |        |        |        |     


OPTION 1
   *    |-25     |     -25|        |        |        |        |     
   *    |        |-20  -20|        |        |        |        |     
   *    |        |        |-25  -25|        |        |        |     
   *    |        |        |-20  -20|        |        |        |     

OPTION 2
   *    |-25     |        |     -25|        |        |        |     
   *    |        |-20     |     -20|        |        |        |     
   *    |        |        |        |-15     |     -15|        |    
   *    |        |        |        |-30     |        |     -30|    
   *    |        |        |        |        |        |        |     
   *
   */
  function reverse($ledger_entries, $stamp = null) {
    pr(array('Entry::reverse',
	     compact('ledger_entries', 'stamp')));

    // If the user only wants to reverse one ID, we'll allow it
    if (!is_array($ledger_entries))
      $ledger_entries = $this->find
	('all', array
	 ('contain' => false,
	  'conditions' => array('Entry.id' => $ledger_entries)));

    $A = new Account();

    $ar_account_id = $A->accountReceivableAccountID();
    $receipt_account_id = $A->receiptAccountID();

    $transaction_id = null;
    foreach ($ledger_entries AS $entry) {
      $entry = $entry['Entry'];
      $amount = -1*$entry['amount'];

      if (isset($entry['credit_account_id']))
	$refund_account_id = $entry['credit_account_id'];
      elseif (isset($entry['CreditLedger']['Account']['id']))
	$refund_account_id = $entry['CreditLedger']['Account']['id'];
      elseif (isset($entry['credit_ledger_id']))
	$refund_account_id = $this->Ledger->accountID($entry['credit_ledger_id']);
      else
	return null;

      // post new refund in the income account
      $ids = $A->postEntry
	(array('transaction_id' => $transaction_id),
	 null,
	 array('debit_ledger_id' => $A->currentLedgerID($ar_account_id),
	       'credit_ledger_id' => $A->currentLedgerID($refund_account_id),
	       'effective_date' => $entry['effective_date'],
	       'through_date' => $entry['through_date'],
	       'amount' => $amount,
	       'lease_id' => $entry['lease_id'],
	       'customer_id' => $entry['customer_id'],
	       'comment' => "Refund; Entry #{$entry['id']}",
	       ),
	 array('debit'  => array
	       (array('Entry' =>
		      array('id' => $entry['id'],
			    'amount' => $amount))),
	       )
	 );

      if ($ids['error'])
	return null;
      $transaction_id = $ids['transaction_id'];
      
      pr(array('checkpoint' => 'Posted Refund Ledger Entry',
	       compact('ids', 'amount', 'refund_account_id', 'ar_account_id')));
    }

    return true;
  }


  /**************************************************************************
   **************************************************************************
   **************************************************************************
   * function: stats
   *  - Returns summary data from the requested ledger entry
   */
  function stats($id = null, $query = null, $set = null) {
    $this->queryInit($query);
    unset($query['group']);

    if (!isset($query['link']['DoubleEntry']))
      $query['link']['DoubleEntry'] = array();
/*     if (!isset($query['link']['DoubleEntry']['fields'])) */
/*       $query['link']['DoubleEntry']['fields'] = array(); */

    if (isset($id))
      $query['conditions'][] = array('Entry.id' => $id);

    if (isset($set))
      $set = strtoupper($set);

    //pr(array('stats()', compact('id', 'query', 'set')));

    $rtypes = array('charge', 'payment',
		    // 'debit', 'credit',
		    );

    $stats = array();
    foreach($rtypes AS $rtype) {
      $Rtype = ucfirst($rtype);

      if (($rtype == 'charge'  && (!isset($set) || $set == 'PAYMENT')) ||
	  ($rtype == 'payment' && (!isset($set) || $set == 'CHARGE'))
/* 	  ($rtype == 'debit'   && (!isset($set) || $set == 'CREDIT'))  || */
/* 	  ($rtype == 'credit'  && (!isset($set) || $set == 'DEBIT')) */
	  ) {

	$rquery = $query;
	$rquery['link'][$Rtype] =
	  array('fields' => array("SUM(COALESCE(Applied{$Rtype}.amount,0)) AS reconciled"));

	$rquery['fields'] = array();
	//$rquery['fields'][] = "SUM(DoubleEntry.amount) AS total";
	$rquery['fields'][] = "SUM(DoubleEntry.amount) - SUM(COALESCE(Applied{$Rtype}.amount,0)) AS balance";
	$rquery['conditions'][] = array("Applied{$Rtype}.id !=" => null);

	$result = $this->find('first', $rquery);
	//pr(compact('Rtype', 'rquery', 'result'));

	$sumfld = $Rtype;
	$stats[$sumfld] = $result[0];
/* 	if (!isset($stats[$sumfld]['applied'])) */
/* 	  $stats[$sumfld]['applied'] = 0; */
      }
    }

    return $stats;
  }

}