<?php
// +----------------------------------------------------------------------+
// | Anuko Time Tracker
// +----------------------------------------------------------------------+
// | Copyright (c) Anuko International Ltd. (https://www.anuko.com)
// +----------------------------------------------------------------------+
// | LIBERAL FREEWARE LICENSE: This source code document may be used
// | by anyone for any purpose, and freely redistributed alone or in
// | combination with other software, provided that the license is obeyed.
// |
// | There are only two ways to violate the license:
// |
// | 1. To redistribute this code in source form, with the copyright
// |    notice or license removed or altered. (Distributing in compiled
// |    forms without embedded copyright notices is permitted).
// |
// | 2. To redistribute modified versions of this code in *any* form
// |    that bears insufficient indications that the modifications are
// |    not the work of the original author(s).
// |
// | This license applies to this document only, not any other software
// | that it may be combined with.
// |
// +----------------------------------------------------------------------+
// | Contributors:
// | https://www.anuko.com/time_tracker/credits.htm
// +----------------------------------------------------------------------+

import('ttClientHelper');
import('DateAndTime');

// Class ttInvoiceHelper is used for help with invoices.
class ttInvoiceHelper {

  // insert - inserts an invoice in database.
  static function insert($fields)
  {
    $mdb2 = getConnection();

    $team_id = (int) $fields['team_id'];
    $name = $fields['name'];
    if (!$name) return false;

    $client_id = (int) $fields['client_id'];
    $date = $fields['date'];
    if (array_key_exists('status', $fields)) { // Key exists and may be NULL during migration of data.
      $status_f = ', status';
      $status_v = ', '.$mdb2->quote($fields['status']);
    }

    // Insert a new invoice record.
    $sql = "insert into tt_invoices (team_id, name, date, client_id $status_f)
      values($team_id, ".$mdb2->quote($name).", ".$mdb2->quote($date).", $client_id $status_v)"; 
    $affected = $mdb2->exec($sql);

    if (is_a($affected, 'PEAR_Error')) return false;

    $last_id = 0;
    $sql = "select last_insert_id() as last_insert_id";
    $res = $mdb2->query($sql);
    $val = $res->fetchRow();
    $last_id = $val['last_insert_id'];

    return $last_id;
  }

  // getInvoice - obtains invoice data from the database.
  static function getInvoice($invoice_id) {
    global $user;
    $mdb2 = getConnection();

    if ($user->isClient()) $client_part = " and client_id = $user->client_id";

    $sql = "select * from tt_invoices where id = $invoice_id and team_id = $user->team_id $client_part and status = 1";
    $res = $mdb2->query($sql);
    if (!is_a($res, 'PEAR_Error')) {
      if ($val = $res->fetchRow())
        return $val;
    }
    return false;
  }

  // The getInvoiceByName looks up an invoice by name.
  static function getInvoiceByName($invoice_name) {

    $mdb2 = getConnection();
    global $user;

    $sql = "select id from tt_invoices where team_id = $user->team_id and name = ".$mdb2->quote($invoice_name)." and status = 1";
    $res = $mdb2->query($sql);
    if (!is_a($res, 'PEAR_Error')) {
      $val = $res->fetchRow();
      if ($val['id']) {
        return $val;
      }
    }
    return false;
  }

  // The isPaid determines if an invoice is paid by looking at the paid status of its items.
  // If any non-paid item is found, the entire invoice is considered not paid.
  // Therefore, the paid status of the invoice is a calculated value.
  // This is because we maintain the paid status on individual item level.
  static function isPaid($invoice_id) {

    $mdb2 = getConnection();
    global $user;

    $sql = "select count(*) as count from tt_log where invoice_id = $invoice_id and status = 1 and paid < 1";
    $res = $mdb2->query($sql);
    if (!is_a($res, 'PEAR_Error')) {
      $val = $res->fetchRow();
      if ($val['count'] > 0)
        return false; // A non-paid time item exists.
    }
    $sql = "select count(*) as count from tt_expense_items where invoice_id = $invoice_id and status = 1 and paid < 1";
    $res = $mdb2->query($sql);
    if (!is_a($res, 'PEAR_Error')) {
      $val = $res->fetchRow();
      if ($val['count'] > 0)
        return false; // A non-paid expense item exists.
      else
        return true; // All time and expense items in invoice are paid.
    }
    return false;
  }

  // markPaid marks invoice items as paid.
  static function markPaid($invoice_id, $mark_paid = true) {

    global $user;
    $mdb2 = getConnection();

    $paid_status = $mark_paid ? 1 : 0;
    $sql = "update tt_log set paid = $paid_status where invoice_id = $invoice_id and status = 1";
    $affected = $mdb2->exec($sql);
    if (is_a($affected, 'PEAR_Error')) return false;

    $sql = "update tt_expense_items set paid = $paid_status where invoice_id = $invoice_id and status = 1";
    $affected = $mdb2->exec($sql);
    if (is_a($affected, 'PEAR_Error')) return false;

    return true;
  }

  // The getInvoiceItems retrieves tt_log items associated with the invoice. 
  static function getInvoiceItems($invoice_id) {
    global $user;
    $mdb2 = getConnection();

    // At this time only detailed invoice is supported.
    // It is anticipated to support "totals only" option later on.

    // Our query is different depending on tracking mode.
    if (MODE_TIME == $user->tracking_mode) {
      // In "time only" tracking mode there is a single user rate.
      $sql = "select l.date as date, 1 as type, u.name as user_name, p.name as project_name,
      t.name as task_name, l.comment as note,
      time_format(l.duration, '%k:%i') as duration,
      cast(l.billable * u.rate * time_to_sec(l.duration)/3600 as decimal(10, 2)) as cost,
      l.paid as paid from tt_log l
      inner join tt_users u on (l.user_id = u.id)
      left join tt_projects p on (p.id = l.project_id)
      left join tt_tasks t on (t.id = l.task_id)
      where l.status = 1 and l.billable = 1 and l.invoice_id = $invoice_id order by l.date, u.name";
    } else {
      $sql = "select l.date as date, 1 as type, u.name as user_name, p.name as project_name,
        t.name as task_name, l.comment as note,
        time_format(l.duration, '%k:%i') as duration,
        cast(l.billable * coalesce(upb.rate, 0) * time_to_sec(l.duration)/3600 as decimal(10, 2)) as cost,
        l.paid as paid from tt_log l
        inner join tt_users u on (l.user_id = u.id)
        left join tt_projects p on (p.id = l.project_id)
        left join tt_tasks t on (t.id = l.task_id)
        left join tt_user_project_binds upb on (upb.user_id = l.user_id and upb.project_id = l.project_id)
        where l.status = 1 and l.billable = 1 and l.invoice_id = $invoice_id order by l.date, u.name";
    }

    // If we have expenses, we need to do a union with a separate query for expense items from tt_expense_items table.
    if ($user->isPluginEnabled('ex')) {
      $sql_for_expense_items = "select ei.date as date, 2 as type, u.name as user_name, p.name as project_name,
        null as task_name, ei.name as note,
        null as duration, ei.cost as cost,
        ei.paid as paid from tt_expense_items ei
        inner join tt_users u on (ei.user_id = u.id)
        left join tt_projects p on (p.id = ei.project_id)
        where ei.invoice_id = $invoice_id and ei.status = 1";

      // Construct a union.
      $sql = "($sql) union all ($sql_for_expense_items)";

      $sort_part = " order by date, user_name, type";
      $sql .= $sort_part;
    }

    $res = $mdb2->query($sql);
    if (!is_a($res, 'PEAR_Error')) {
      $dt = new DateAndTime(DB_DATEFORMAT);
      while ($val = $res->fetchRow()) {
        $dt->parseVal($val['date']);
        $val['date'] = $dt->toString($user->date_format);
        $result[] = $val;
      }
    }
    return $result;
  }

  // delete - deletes the invoice data from the database.
  static function delete($invoice_id, $delete_invoice_items) {
    global $user;
    $mdb2 = getConnection();

    // Handle custom field log records.
    if ($delete_invoice_items) {
      $sql = "update tt_custom_field_log set status = NULL where log_id in (select id from tt_log where invoice_id = $invoice_id and status = 1)";
      $affected = $mdb2->exec($sql);
      if (is_a($affected, 'PEAR_Error')) return false;
    }

    // Handle time records.
    if ($delete_invoice_items)
      $sql = "update tt_log set status = NULL where invoice_id = $invoice_id";
    else
      $sql = "update tt_log set invoice_id = NULL where invoice_id = $invoice_id";
    $affected = $mdb2->exec($sql);
    if (is_a($affected, 'PEAR_Error')) return false;

    // Handle expense items.
    if ($delete_invoice_items)
      $sql = "update tt_expense_items set status = NULL where invoice_id = $invoice_id";
    else
      $sql = "update tt_expense_items set invoice_id = NULL where invoice_id = $invoice_id";
    $affected = $mdb2->exec($sql);
    if (is_a($affected, 'PEAR_Error')) return false;

    $sql = "update tt_invoices set status = NULL where id = $invoice_id and team_id = $user->team_id";
    $affected = $mdb2->exec($sql);
    return (!is_a($affected, 'PEAR_Error'));
  }

  // The invoiceableItemsExist determines whether invoiceable records exist in the specified period.
  static function invoiceableItemsExist($fields) {

    $mdb2 = getConnection();
    global $user;

    $client_id = (int) $fields['client_id'];

    $start_date = new DateAndTime($user->date_format, $fields['start_date']);
    $start = $start_date->toString(DB_DATEFORMAT);

    $end_date = new DateAndTime($user->date_format, $fields['end_date']);
    $end = $end_date->toString(DB_DATEFORMAT);

    if (isset($fields['project_id'])) $project_id = (int) $fields['project_id'];

    // Our query is different depending on tracking mode.
    if (MODE_TIME == $user->tracking_mode) {
      // In "time only" tracking mode there is a single user rate.
      $sql = "select count(*) as num from tt_log l, tt_users u
        where l.status = 1 and l.client_id = $client_id and l.invoice_id is NULL
        and l.date >= ".$mdb2->quote($start)." and l.date <= ".$mdb2->quote($end)."
        and l.user_id = u.id
        and l.billable = 1"; // l.billable * u.rate * time_to_sec(l.duration)/3600 > 0 // See explanation below.
    } else {
      // sql part for project id.
      if ($project_id) $project_part = " and l.project_id = $project_id";

      // When we have projects, rates are defined for each project in tt_user_project_binds table.
      $sql = "select count(*) as num from tt_log l, tt_user_project_binds upb
        where l.status = 1 and l.client_id = $client_id $project_part and l.invoice_id is NULL
        and l.date >= ".$mdb2->quote($start)." and l.date <= ".$mdb2->quote($end)."
        and upb.user_id = l.user_id and upb.project_id = l.project_id
        and l.billable = 1"; // l.billable * upb.rate * time_to_sec(l.duration)/3600 > 0
        // Users with a lot of clients and projects (Jaro) may forget to set user rates properly.
        // Specifically, user rate may be set to 0 on a project, by mistake. This leads to error.no_invoiceable_items
        // and increased support cost. Commenting out allows us to include 0 cost items in invoices so that
        // the problem becomes obvious.

        // TODO: If the above turns out useful, rework the query to simplify it by removing left join.
    }
    $res = $mdb2->query($sql);
    if (!is_a($res, 'PEAR_Error')) {
      $val = $res->fetchRow();
      if ($val['num']) {
        return true;
      }
    }

    // sql part for project id.
    if ($project_id) $project_part = " and ei.project_id = $project_id";

    $sql = "select count(*) as num from tt_expense_items ei
      where ei.client_id = $client_id $project_part and ei.invoice_id is NULL
      and ei.date >= ".$mdb2->quote($start)." and ei.date <= ".$mdb2->quote($end)."
      and ei.cost <> 0 and ei.status = 1";
    $res = $mdb2->query($sql);
    if (!is_a($res, 'PEAR_Error')) {
      $val = $res->fetchRow();
      if ($val['num']) {
        return true;
      }
    }

    return false;
  }

  // createInvoice - marks items for invoice as belonging to it (with its reference number).
  static function createInvoice($fields) {

    $mdb2 = getConnection();
    global $user;

    $name = $fields['name'];
    if (!$name) return false;

    $client_id = (int) $fields['client_id'];

    $invoice_date = new DateAndTime($user->date_format, $fields['date']);
    $date = $invoice_date->toString(DB_DATEFORMAT);

    $start_date = new DateAndTime($user->date_format, $fields['start_date']);
    $start = $start_date->toString(DB_DATEFORMAT);

    $end_date = new DateAndTime($user->date_format, $fields['end_date']);
    $end = $end_date->toString(DB_DATEFORMAT);

    if (isset($fields['project_id'])) $project_id = (int) $fields['project_id'];

    // Create a new invoice record.
    $sql = "insert into tt_invoices (team_id, name, date, client_id)
      values($user->team_id, ".$mdb2->quote($name).", ".$mdb2->quote($date).", $client_id)";
    $affected = $mdb2->exec($sql);
    if (is_a($affected, 'PEAR_Error')) return false;

    // Mark associated invoice items with invoice id.
    $last_id = 0;
    $sql = "select last_insert_id() as last_insert_id";
    $res = $mdb2->query($sql);
    $val = $res->fetchRow();
    $last_id = $val['last_insert_id'];

    // Our update sql is different depending on tracking mode.
    if (MODE_TIME == $user->tracking_mode) {
      // In "time only" tracking mode there is a single user rate.
      $sql = "update tt_log l
        left join tt_users u on (u.id = l.user_id)
        set l.invoice_id = $last_id
        where l.status = 1 and l.client_id = $client_id and l.invoice_id is NULL
        and l.date >= ".$mdb2->quote($start)." and l.date <= ".$mdb2->quote($end)."
        and l.billable = 1"; // l.billable * u.rate * time_to_sec(l.duration)/3600 > 0"; // See explanation below.
    } else {
       // sql part for project id.
      if ($project_id) $project_part = " and l.project_id = $project_id";

      // When we have projects, rates are defined for each project in tt_user_project_binds.
      $sql = "update tt_log l
        left join tt_user_project_binds upb on (upb.user_id = l.user_id and upb.project_id = l.project_id)
        set l.invoice_id = $last_id
        where l.status = 1 and l.client_id = $client_id $project_part and l.invoice_id is NULL
        and l.date >= ".$mdb2->quote($start)." and l.date <= ".$mdb2->quote($end)."
        and l.billable = 1"; //  l.billable * upb.rate * time_to_sec(l.duration)/3600 > 0";
        // Users with a lot of clients and projects (Jaro) may forget to set user rates properly.
        // Specifically, user rate may be set to 0 on a project, by mistake. This leads to error.no_invoiceable_items
        // and increased support cost. Commenting out allows us to include 0 cost items in invoices so that
        // the problem becomes obvious.

        // TODO: If the above turns out useful, rework the query to simplify it by removing left join.
    }
    $affected = $mdb2->exec($sql);
    if (is_a($affected, 'PEAR_Error'))
      return false;

    // sql part for project id.
    if ($project_id) $project_part = " and project_id = $project_id";

    $sql = "update tt_expense_items set invoice_id = $last_id where client_id = $client_id $project_part and invoice_id is NULL
      and date >= ".$mdb2->quote($start)." and date <= ".$mdb2->quote($end)." and cost <> 0 and status = 1";
    $affected = $mdb2->exec($sql);
    return (!is_a($affected, 'PEAR_Error'));
  }

  // prepareInvoiceBody - prepares an email body for invoice.
  static function prepareInvoiceBody($invoice_id, $comment)
  {
    global $user;
    global $i18n;

    $invoice = ttInvoiceHelper::getInvoice($invoice_id);
    $client = ttClientHelper::getClient($invoice['client_id'], true);
    $invoice_items = ttInvoiceHelper::getInvoiceItems($invoice_id);

    $tax_percent = $client['tax'];

    $subtotal = 0;
    $tax = 0;
    foreach($invoice_items as $item)
      $subtotal += $item['cost'];
    if ($tax_percent) {
      $tax_expenses = $user->isPluginEnabled('et');
      foreach($invoice_items as $item) {
        if ($item['type'] == 2 && !$tax_expenses)
          continue;
        $tax += round($item['cost'] * $tax_percent / 100, 2);
      }
    }
    $total = $subtotal + $tax;

    $subtotal = htmlspecialchars($user->currency).' '.str_replace('.', $user->decimal_mark, sprintf('%8.2f', round($subtotal, 2)));
    if ($tax) $tax = htmlspecialchars($user->currency).' '.str_replace('.', $user->decimal_mark, sprintf('%8.2f', round($tax, 2)));
    $total = htmlspecialchars($user->currency).' '.str_replace('.', $user->decimal_mark, sprintf('%8.2f', round($total, 2)));

    if ('.' != $user->decimal_mark) {
      foreach ($invoice_items as &$item) {
        $item['cost'] = str_replace('.', $user->decimal_mark, $item['cost']);
      }
      unset($item); // Unset the reference. If we don't, the foreach loop below modifies the array while printing.
                    // See http://stackoverflow.com/questions/8220399/php-foreach-pass-by-reference-last-element-duplicating-bug
    }

    // Define some styles to use in email.
    $style_title = 'text-align: center; font-size: 15pt; font-family: Arial, Helvetica, sans-serif;';
    $style_tableHeader = 'font-weight: bold; background-color: #a6ccf7; text-align: left;';
    $style_tableHeaderCentered = 'font-weight: bold; background-color: #a6ccf7; text-align: center;';

    // Start creating email body.
    $body = '<html>';
    $body .= '<head><meta http-equiv="content-type" content="text/html; charset='.CHARSET.'"></head>';
    $body .= '<body>';

    // Output title.
    $body .= '<p style="'.$style_title.'">'.$i18n->getKey('title.invoice').' '.htmlspecialchars($invoice['name']).'</p>';

    // Output comment.
    if($comment) $body .= '<p>'.htmlspecialchars($comment).'</p>';

    // Output invoice info.
    $body .= '<table>';
    $body .= '<tr><td><b>'.$i18n->getKey('label.date').':</b> '.$invoice['date'].'</td></tr>';
    $body .= '<tr><td><b>'.$i18n->getKey('label.client').':</b> '.htmlspecialchars($client['name']).'</td></tr>';
    $body .= '<tr><td><b>'.$i18n->getKey('label.client_address').':</b> '.htmlspecialchars($client['address']).'</td></tr>';
    $body .= '</table>';

    $body .= '<p></p>';

    // Output invoice items.
    $body .= '<table border="0" cellpadding="4" cellspacing="0" width="100%">';
    $body .= '<tr>';
    $body .= '<td style="'.$style_tableHeader.'">'.$i18n->getKey('label.date').'</td>';
    $body .= '<td style="'.$style_tableHeader.'">'.$i18n->getKey('form.invoice.person').'</td>';
    if (MODE_PROJECTS == $user->tracking_mode || MODE_PROJECTS_AND_TASKS == $user->tracking_mode)
      $body .= '<td style="'.$style_tableHeader.'">'.$i18n->getKey('label.project').'</td>';
    if (MODE_PROJECTS_AND_TASKS == $user->tracking_mode)
      $body .= '<td style="'.$style_tableHeader.'">'.$i18n->getKey('label.task').'</td>';
    $body .= '<td style="'.$style_tableHeader.'">'.$i18n->getKey('label.note').'</td>';
    $body .= '<td style="'.$style_tableHeaderCentered.'" width="5%">'.$i18n->getKey('label.duration').'</td>';
    $body .= '<td style="'.$style_tableHeaderCentered.'" width="5%">'.$i18n->getKey('label.cost').'</td>';
    $body .= '</tr>';
    foreach ($invoice_items as $item) {
      $body .= '<tr>';
      $body .= '<td>'.$item['date'].'</td>';
      $body .= '<td>'.htmlspecialchars($item['user_name']).'</td>';
      if (MODE_PROJECTS == $user->tracking_mode || MODE_PROJECTS_AND_TASKS == $user->tracking_mode)
        $body .= '<td>'.htmlspecialchars($item['project_name']).'</td>';
      if (MODE_PROJECTS_AND_TASKS == $user->tracking_mode)
        $body .= '<td>'.htmlspecialchars($item['task_name']).'</td>';
      $body .= '<td>'.htmlspecialchars($item['note']).'</td>';
      $body .= '<td align="right">'.$item['duration'].'</td>';
      $body .= '<td align="right">'.$item['cost'].'</td>';
      $body .= '</tr>';
    }
    // Output summary.
    $colspan = 4;
    if (MODE_PROJECTS == $user->tracking_mode)
      $colspan++;
    elseif (MODE_PROJECTS_AND_TASKS == $user->tracking_mode)
      $colspan += 2;
    $body .= '<tr><td>&nbsp;</td></tr>';
    if ($tax) {
      $body .= '<tr><td colspan="'.$colspan.'" align="right"><b>'.$i18n->getKey('label.subtotal').':</b></td><td nowrap align="right">'.$subtotal.'</td></tr>';
      $body .= '<tr><td colspan="'.$colspan.'" align="right"><b>'.$i18n->getKey('label.tax').':</b></td><td nowrap align="right">'.$tax.'</td></tr>';
    }
    $body .= '<tr><td colspan="'.$colspan.'" align="right"><b>'.$i18n->getKey('label.total').':</b></td><td nowrap align="right">'.$total.'</td></tr>';
    $body .= '</table>';

    // Output footer.
    if (!defined('REPORT_FOOTER') || !(REPORT_FOOTER == false))
      $body .= '<p style="text-align: center;">'.$i18n->getKey('form.mail.footer').'</p>';

    // Finish creating email body.
    $body .= '</body></html>';

    return $body;
  }
}