<?php
/**
 * What Dealroot did for the business.
 *
 * @package Dealroot
 */

namespace Dealroot;

defined( 'ABSPATH' ) || exit;

/**
 * The last 30 days in what the plugin itself did: enquiries answered through it and how many of
 * them became customers, confirmations sent, spam sorted out. Only what is known is counted:
 * a deal is listed where Dealroot was part of it, not as if Dealroot alone won it.
 *
 * Once a month, the same goes to Telegram with the week in short.
 *
 * phpcs:disable WordPress.DB.DirectDatabaseQuery.DirectQuery, WordPress.DB.DirectDatabaseQuery.NoCaching
 */
class Impact {

	const HOOK   = 'dealroot_impact_monthly';
	const OPTION = 'dealroot_impact_sent';
	const DAYS   = 30;

	/**
	 * Hooks.
	 */
	public function register() {
		add_action( 'init', array( __CLASS__, 'schedule' ) );
		add_action( self::HOOK, array( __CLASS__, 'monthly' ) );
	}

	/**
	 * Looks once a day whether a new month began.
	 */
	public static function schedule() {
		if ( ! wp_next_scheduled( self::HOOK ) ) {
			wp_schedule_event( time() + HOUR_IN_SECONDS, 'daily', self::HOOK );
		}
	}

	/**
	 * Remembers how a lead was first answered, e.g. "reply", "ai" or "telegram".
	 *
	 * @param int    $lead_id Lead ID.
	 * @param string $via     Way.
	 */
	public static function answered( $lead_id, $via ) {
		global $wpdb;

		$wpdb->query(
			$wpdb->prepare(
				"UPDATE %i SET answered_via = %s WHERE id = %d AND answered_via = ''",
				Installer::table(),
				sanitize_key( $via ),
				(int) $lead_id
			)
		);
	}

	/**
	 * Lines about the last 30 days, most valuable first.
	 *
	 * @return array<int, array{key: string, text: string}>
	 */
	public static function items() {
		global $wpdb;

		$since = gmdate( 'Y-m-d H:i:s', time() - self::DAYS * DAY_IN_SECONDS );
		$items = array();

		$answered = $wpdb->get_row(
			$wpdb->prepare(
				"SELECT COUNT(*) AS leads, SUM( CASE WHEN status = 'won' THEN 1 ELSE 0 END ) AS won FROM %i WHERE answered_via <> '' AND created_at >= %s",
				Installer::table(),
				$since
			)
		);

		if ( $answered && (int) $answered->leads > 0 ) {
			$items[] = array(
				'key'  => 'answered',
				'text' => sprintf(
					/* translators: 1: enquiries, 2: customers, 3: amount */
					_n( '%1$s enquiry answered through Dealroot – with a quick reply, the AI assistant or from Telegram. %2$s of them became customers, worth %3$s.', '%1$s enquiries answered through Dealroot – with a quick reply, the AI assistant or from Telegram. %2$s of them became customers, worth %3$s.', (int) $answered->leads, 'dealroot' ),
					number_format_i18n( (int) $answered->leads ),
					number_format_i18n( (int) $answered->won ),
					Admin\Format::money_list( self::revenue( 'answered_via', $since ) )
				),
			);
		}

		$confirmed = (int) $wpdb->get_var(
			$wpdb->prepare( 'SELECT COUNT(*) FROM %i WHERE ai_confirmed_at >= %s', Installer::table(), $since )
		);

		if ( $confirmed > 0 ) {
			$items[] = array(
				'key'  => 'confirmed',
				/* translators: %s: number of enquiries */
				'text' => sprintf( _n( '%s enquiry got a personal confirmation within a minute.', '%s enquiries got a personal confirmation within a minute.', $confirmed, 'dealroot' ), number_format_i18n( $confirmed ) ),
			);
		}

		$spam = (int) $wpdb->get_var(
			$wpdb->prepare( "SELECT COUNT(*) FROM %i WHERE status = 'spam' AND created_at >= %s", Installer::table(), $since )
		);

		if ( $spam > 0 ) {
			$items[] = array(
				'key'  => 'spam',
				/* translators: %s: number of messages */
				'text' => sprintf( _n( '%s spam message was sorted out, so you did not have to read it.', '%s spam messages were sorted out, so you did not have to read them.', $spam, 'dealroot' ), number_format_i18n( $spam ) ),
			);
		}

		/**
		 * Filters what Dealroot did in the last 30 days.
		 *
		 * @param array  $items Items with key and text.
		 * @param string $since UTC start.
		 */
		return array_values( (array) apply_filters( 'dealroot_impact_items', $items, $since ) );
	}

	/**
	 * Revenue of won leads with a column set, per currency.
	 *
	 * @param string $column answered_via.
	 * @param string $since  UTC start.
	 * @return array<string, float>
	 */
	private static function revenue( $column, $since ) {
		global $wpdb;

		$rows = $wpdb->get_results(
			$wpdb->prepare(
				"SELECT currency, SUM( COALESCE( value, 0 ) ) AS revenue FROM %i WHERE %i <> '' AND status = 'won' AND created_at >= %s GROUP BY currency",
				Installer::table(),
				$column,
				$since
			)
		);

		$default = (string) Settings::get( 'currency' );
		$revenue = array();

		foreach ( (array) $rows as $row ) {
			$currency             = '' !== (string) $row->currency ? (string) $row->currency : $default;
			$revenue[ $currency ] = ( $revenue[ $currency ] ?? 0 ) + (float) $row->revenue;
		}

		return array_filter( $revenue );
	}

	/**
	 * On the first days of a month, sends the last 30 days to Telegram, once.
	 */
	public static function monthly() {
		$month = wp_date( 'Y-m' );

		if ( (int) wp_date( 'j' ) > 3 || get_option( self::OPTION ) === $month || ! Notifier::telegram_ready() || ! Settings::get( 'telegram_weekly' ) ) {
			return;
		}

		$items = self::items();
		update_option( self::OPTION, $month, false );

		if ( ! $items ) {
			return;
		}

		$esc   = static function ( $text ) {
			return htmlspecialchars( (string) $text, ENT_NOQUOTES, 'UTF-8' );
		};
		$lines = array( '<b>' . $esc( __( 'What Dealroot did in the last 30 days', 'dealroot' ) ) . '</b>', '' );

		foreach ( $items as $item ) {
			$lines[] = '• ' . $esc( $item['text'] );
		}

		Notifier::send_telegram( Settings::get( 'telegram_token' ), Settings::get( 'telegram_chat_id' ), implode( "\n", $lines ) );
	}
}