<?php
/*
 +--------------------------------------------------------------------+
 | Copyright CiviCRM LLC. All rights reserved.                        |
 |                                                                    |
 | This work is published under the GNU AGPLv3 license with some      |
 | permitted exceptions and without any warranty. For full license    |
 | and copyright information, see https://civicrm.org/licensing       |
 +--------------------------------------------------------------------+
 */

/**
 *
 * @package CRM
 * @copyright CiviCRM LLC https://civicrm.org/licensing
 *
 * Order class.
 *
 * This class is intended to become the object to manage orders, including via Order.api.
 *
 * As of writing it is in the process of having appropriate functions built up.
 */
class CRM_Financial_BAO_Order {

  /**
   * Price set id.
   *
   * @var int
   */
  protected $priceSetID;

  /**
   * Selected price items in the format we see in forms.
   *
   * ie.
   * [price_3 => 4, price_10 => 7]
   * is equivalent to 'option_value 4 for radio price field 3 and
   * a quantity of 7 for text price field 10.
   *
   * @var array
   */
  protected $priceSelection = [];

  /**
   * Override for financial type id.
   *
   * Used when the financial type id is to be overridden for all line items
   * (as can happen in backoffice forms)
   *
   * @var int
   */
  protected $overrideFinancialTypeID;

  /**
   * Override for the total amount of the order.
   *
   * When there is a single line item the order total may be overriden.
   *
   * @var float
   */
  protected $overrideTotalAmount;

  /**
   * Line items in the order.
   *
   * @var array
   */
  protected $lineItems = [];

  /**
   * Metadata for price fields.
   *
   * @var array
   */
  protected $priceFieldMetadata = [];

  /**
   * Get Set override for total amount of the order.
   *
   * @return float|false
   */
  public function getOverrideTotalAmount() {
    if (count($this->getPriceOptions()) !== 1) {
      return FALSE;
    }
    return $this->overrideTotalAmount ?? FALSE;
  }

  /**
   * Set override for total amount.
   *
   * @param float $overrideTotalAmount
   */
  public function setOverrideTotalAmount(float $overrideTotalAmount) {
    $this->overrideTotalAmount = $overrideTotalAmount;
  }

  /**
   * Get override for total amount.
   *
   * @return int| FALSE
   */
  public function getOverrideFinancialTypeID() {
    if (count($this->getPriceOptions()) !== 1) {
      return FALSE;
    }
    return $this->overrideFinancialTypeID ?? FALSE;
  }

  /**
   * Set override for financial type ID.
   *
   * @param int $overrideFinancialTypeID
   */
  public function setOverrideFinancialTypeID(int $overrideFinancialTypeID) {
    $this->overrideFinancialTypeID = $overrideFinancialTypeID;
  }

  /**
   * Getter for price set id.
   *
   * @return int
   */
  public function getPriceSetID(): int {
    return $this->priceSetID;
  }

  /**
   * Setter for price set id.
   *
   * @param int $priceSetID
   */
  public function setPriceSetID(int $priceSetID) {
    $this->priceSetID = $priceSetID;
  }

  /**
   * Getter for price selection.
   *
   * @return array
   */
  public function getPriceSelection(): array {
    return $this->priceSelection;
  }

  /**
   * Setter for price selection.
   *
   * @param array $priceSelection
   */
  public function setPriceSelection(array $priceSelection) {
    $this->priceSelection = $priceSelection;
  }

  /**
   * Price options the simplified price fields selections.
   *
   * ie. the 'price_' is stripped off the key name and the field ID
   * is cast to an integer.
   *
   * @return array
   */
  public function getPriceOptions():array {
    $priceOptions = [];
    foreach ($this->getPriceSelection() as $fieldName => $value) {
      $fieldID = substr($fieldName, 6);
      $priceOptions[(int) $fieldID] = $value;
    }
    return $priceOptions;
  }

  /**
   * Get the metadata for the given field.
   *
   * @param int $id
   *
   * @return array
   * @throws \CiviCRM_API3_Exception
   */
  public function getPriceFieldSpec(int $id) :array {
    if (!isset($this->priceFieldMetadata[$id])) {
      $this->priceFieldMetadata = CRM_Price_BAO_PriceSet::getCachedPriceSetDetail($this->getPriceSetID())['fields'];
    }
    return $this->priceFieldMetadata[$id];
  }

  /**
   * Set the price field selection from an array of params containing price fields.
   *
   * This function takes the sort of 'anything & everything' parameters that come in from the
   * form layer and filters them before assigning them to the priceSelection property.
   *
   * @param array $input
   */
  public function setPriceSelectionFromUnfilteredInput(array $input) {
    foreach ($input as $fieldName => $value) {
      if (strpos($fieldName, 'price_') === 0) {
        $fieldID = substr($fieldName, 6);
        if (is_numeric($fieldID)) {
          $this->priceSelection[$fieldName] = $value;
        }
      }
    }
  }

  /**
   * Get line items.
   *
   * return array
   *
   * @throws \CiviCRM_API3_Exception
   */
  public function getLineItems():array {
    if (empty($this->lineItems)) {
      $this->lineItems = $this->calculateLineItems();
    }
    return $this->lineItems;
  }

  /**
   * @return array
   * @throws \CiviCRM_API3_Exception
   */
  protected function calculateLineItems(): array {
    $lineItems = [];
    $params = $this->getPriceSelection();
    if ($this->getOverrideTotalAmount() !== FALSE) {
      // We need to do this to keep getLine from doing weird stuff but the goal
      // is to ditch getLine next round of refactoring
      // and make the code more sane.
      $params['total_amount'] = $this->getOverrideTotalAmount();
    }

    foreach ($this->getPriceOptions() as $fieldID => $valueID) {
      $throwAwayArray = [];
      // @todo - still using getLine for now but better to bring it to this class & do a better job.
      $lineItems[$valueID] = CRM_Price_BAO_PriceSet::getLine($params, $throwAwayArray, $this->getPriceSetID(), $this->getPriceFieldSpec($fieldID), $fieldID, 0)[1][$valueID];
    }

    $taxRates = CRM_Core_PseudoConstant::getTaxRates();
    foreach ($lineItems as &$lineItem) {
      // Set any pre-calculation to zero as we will calculate.
      $lineItem['tax_amount'] = 0;
      if ($this->getOverrideFinancialTypeID() !== FALSE) {
        $lineItem['financial_type_id'] = $this->getOverrideFinancialTypeID();
      }
      $taxRate = $taxRates[$lineItem['financial_type_id']] ?? 0;
      if ($this->getOverrideTotalAmount() !== FALSE) {
        if ($taxRate) {
          // Total is tax inclusive.
          $lineItem['tax_amount'] = ($taxRate / 100) * $this->getOverrideTotalAmount();
          $lineItem['line_total'] = $lineItem['unit_price'] = $this->getOverrideTotalAmount() - $lineItem['tax_amount'];
        }
        else {
          $lineItem['line_total'] = $lineItem['unit_price'] = $this->getOverrideTotalAmount();
        }
      }
      elseif ($taxRate) {
        $lineItem['tax_amount'] = ($taxRate / 100) * $lineItem['line_total'];
      }
    }
    return $lineItems;
  }

  /**
   * Get the total tax amount for the order.
   *
   * @return float
   *
   * @throws \CiviCRM_API3_Exception
   */
  public function getTotalTaxAmount() :float {
    $amount = 0.0;
    foreach ($this->getLineItems() as $lineItem) {
      $amount += $lineItem['tax_amount'] ?? 0.0;
    }
    return $amount;
  }

}