<?php

class CRM_Tbusainvoicegen_Timebank {

  /**
   * Live settings
   * const TBBILLABLEFIELD = 'custom_202';
   * const BILLABLEMEMBERFIELD = 'custom_199';
   */
  const TBBILLABLEFIELD = 'custom_9';
  const BILLABLEMEMBERFIELD = 'custom_10';

  /**
   * Set the pricing here.
   * Up to the number of members in single quotes means you pay the second number every 6 months.
   */
  private $priceArray = [
    '34' => 30,
    '49' => 60,
    '79' => 90,
    '119' => 160,
    '149' => 200,
    '199' => 240,
    '249' => 340,
    '349' => 440,
    '499' => 590,
    '749' => 880,
    '1000' => 1200,
    '9999999' => 9999,
  ];

  /**
   * The contact ID of this timebank.
   * @var int
   */
  private $contactId;

  /**
   * The number of billable members.
   * @var int
   */
  private $memberCount;

  /**
   * The price for one period of this timebank.
   * @var float
   */
  private $price;

  /**
   * An array of all the contact IDs for whom a contribution already exists in this billing period.
   * @var array
   */
  public static $contributionExists = [];

  /**
   * A string that represents the current billing period - e.g. "2019-2".
   * First number is the year; second is 1 for Jan-Jun, 2 for Jul-Dec.
   * @var string
   */
  public static $billingPeriod = NULL;

  /**
   * Class constructor.
   */
  public function __construct($cid, $memberCount) {
    $this->cid = $cid;
    $this->memberCount = $memberCount;
  }

  /**
   * Generate invoices (called from API).
   * @param int $cid
   * @return array APIv3 standard response.
   */
  public static function generate($cid = NULL, $billingPeriod = NULL) {
    self::setBillingPeriod($billingPeriod);
    // Get a list of contact IDs for everyone to generate an invoice for.
    $contacts = civicrm_api3('Contact', 'get', [
      'return' => ["id", self::BILLABLEMEMBERFIELD],
      'contact_id' => $cid,
      'contact_type' => 'Organization',
      self::TBBILLABLEFIELD => 1,
      'options' => ['limit' => 0],
    ])['values'];
    self::setContributionExists();
    foreach ($result as $k => $contact) {
      $tb = new CRM_Tbusainvoicegen_Timebank($k, $contact[self::BILLABLEMEMBERFIELD]);
      $price = $tb->setPrice();
    }
  }

  public static function setBillingPeriod($billingPeriod) {
    if ($billingPeriod) {
      self::$billingPeriod = $billingPeriod;
    }
    else {
      // Should we try to auto-calculate it here?  Or nah?
    }
  }

  /**
   * Generate an array of contacts who already have a contribution created in this billing period.
   */
  public static function setContributionExists() {
    // API call to contribution.get to find all records with this billing period
    // Return an array of contact IDs.
  }

  private function setPrice() {
    if ($this->price) {
      return $this->price;
    }
    $adjustedMemberCount = $this->memberCount - 2;
    foreach ($this->priceArray as $members => $cost) {
      if ($adjustedMemberCount <= $members) {
        $this->price = $cost;
        break;
      }
    }
    return $this->price;
  }

}