<?php
/**
 * Weekly summary email.
 *
 * @package Dealroot
 */

namespace Dealroot;

defined( 'ABSPATH' ) || exit;

/**
 * Sends a short weekly overview of leads, deals and contact clicks.
 */
class Digest {

	const HOOK = 'dealroot_weekly_digest';

	/**
	 * Hooks.
	 */
	public function register() {
		add_action( self::HOOK, array( $this, 'send_scheduled' ) );
		add_action( 'update_option_' . Settings::OPTION, array( self::class, 'reschedule' ) );
	}

	/**
	 * Schedules the summary for Monday at 8:00 in the site's time zone, by email, on Telegram
	 * or both.
	 */
	public static function reschedule() {
		wp_clear_scheduled_hook( self::HOOK );

		if ( ! Settings::get( 'digest_enabled' ) && ! self::telegram() ) {
			return;
		}

		$next = new \DateTimeImmutable( 'next monday 08:00', wp_timezone() );

		wp_schedule_event( $next->getTimestamp(), 'weekly', self::HOOK );
	}

	/**
	 * Whether the week goes to Telegram too.
	 *
	 * @return bool
	 */
	private static function telegram() {
		return Settings::get( 'telegram_weekly' ) && Notifier::telegram_ready();
	}

	/**
	 * Cron callback. Stays quiet when nothing happened for two weeks.
	 */
	public function send_scheduled() {
		// The advice of the week is written before it goes out.
		if ( Ai::enabled() ) {
			Ai_Coach::refresh();
		}

		$data = self::data();
		if ( 0 === $data['current']['leads'] && 0 === $data['previous']['leads'] && 0 === ( $data['current']['clicks']['_total'] ?? 0 ) ) {
			return;
		}

		if ( Settings::get( 'digest_enabled' ) ) {
			self::send( $data );
		}

		if ( self::telegram() ) {
			self::send_telegram();
		}
	}

	/**
	 * Sends the week in a few sentences to Telegram.
	 *
	 * @return true|\WP_Error
	 */
	public static function send_telegram() {
		$switched = function_exists( 'switch_to_locale' ) && switch_to_locale( Ai::team_locale() );
		$text     = Insights::telegram( Insights::week(), Ai_Coach::current() );

		if ( $switched ) {
			restore_previous_locale();
		}

		return Notifier::send_telegram( Settings::get( 'telegram_token' ), Settings::get( 'telegram_chat_id' ), $text );
	}

	/**
	 * Recipients: the configured list, or the site admin.
	 *
	 * @return string[]
	 */
	public static function recipients() {
		$list = array_filter( array_map( 'trim', explode( ',', (string) Settings::get( 'digest_recipients' ) ) ), 'is_email' );

		return $list ? array_values( $list ) : array( get_option( 'admin_email' ) );
	}

	/**
	 * Numbers for the last seven days and the seven days before.
	 *
	 * @return array
	 */
	public static function data() {
		$current  = Reports::breakdown( '7d', 'channel', 'first' );
		$previous = self::previous_week();

		return array(
			/** This filter is documented in includes/admin/class-leads-page.php */
			'current'  => array_merge( Reports::empty_row(), (array) apply_filters( 'dealroot_report_totals', Reports::totals( $current ), '7d', 'channel' ) ),
			'previous' => $previous,
			'channels' => array_slice( $current, 0, 5, true ),
			'insights' => Insights::week(),
			'coach'    => Ai_Coach::current(),
		);
	}

	/**
	 * Lead count for days 8 to 14 ago.
	 *
	 * @return array
	 */
	private static function previous_week() {
		$result = Leads::query(
			array(
				'from'     => gmdate( 'Y-m-d H:i:s', time() - 14 * DAY_IN_SECONDS ),
				'to'       => gmdate( 'Y-m-d H:i:s', time() - 7 * DAY_IN_SECONDS ),
				'per_page' => 1,
			)
		);

		return array( 'leads' => $result['total'] );
	}

	/**
	 * Builds and sends the email.
	 *
	 * @param array|null $data Prepared numbers.
	 * @return bool
	 */
	public static function send( $data = null ) {
		$data    = $data ? $data : self::data();
		$current = $data['current'];
		$site    = wp_specialchars_decode( get_bloginfo( 'name' ), ENT_QUOTES );

		/* translators: %s: site name. */
		$subject = sprintf( __( 'Your leads this week – %s', 'dealroot' ), $site );

		$switched = function_exists( 'switch_to_locale' ) && switch_to_locale( Ai::team_locale() );

		ob_start();
		self::render( $data, $site );
		$body = (string) ob_get_clean();

		if ( $switched ) {
			restore_previous_locale();
		}

		/**
		 * Filters the weekly email before it is sent.
		 *
		 * @param array $email to, subject, body.
		 * @param array $data  Numbers.
		 */
		$email = apply_filters(
			'dealroot_digest_email',
			array(
				'to'      => self::recipients(),
				'subject' => $subject,
				'body'    => $body,
			),
			$data
		);

		return wp_mail( $email['to'], $email['subject'], $email['body'], array( 'Content-Type: text/html; charset=UTF-8' ) );
	}

	/**
	 * Email HTML. Inline styles because mail clients ignore stylesheets.
	 *
	 * @param array  $data Numbers.
	 * @param string $site Site name.
	 */
	private static function render( array $data, $site ) {
		$current = $data['current'];
		$delta   = $current['leads'] - $data['previous']['leads'];
		$clicks  = (int) ( $current['clicks']['_total'] ?? 0 );
		$cell    = 'padding:8px 12px;border-bottom:1px solid #eee;';
		?>
		<div style="font-family:-apple-system,BlinkMacSystemFont,'Segoe UI',Roboto,Arial,sans-serif;color:#1d2327;max-width:560px;margin:0 auto;">
			<h1 style="font-size:20px;margin:0 0 4px;"><?php echo esc_html( $site ); ?></h1>
			<p style="color:#646970;margin:0 0 24px;"><?php esc_html_e( 'Last 7 days', 'dealroot' ); ?></p>

			<?php if ( ! empty( $data['coach'] ) ) : ?>
				<div style="margin:0 0 20px;padding:14px 16px;background:#eef5f0;border-radius:6px;line-height:1.5;">
					<p style="margin:0 0 8px;"><?php echo esc_html( $data['coach']['advice'] ); ?></p>
					<?php if ( '' !== $data['coach']['focus'] ) : ?>
						<p style="margin:0;"><strong><?php esc_html_e( 'Worth doing next', 'dealroot' ); ?>:</strong> <?php echo esc_html( $data['coach']['focus'] ); ?></p>
					<?php endif; ?>
				</div>
			<?php endif; ?>

			<?php if ( ! empty( $data['insights'] ) ) : ?>
				<ul style="margin:0 0 24px;padding:0 0 0 18px;line-height:1.5;">
					<?php foreach ( $data['insights'] as $item ) : ?>
						<li style="margin:0 0 6px;"><?php echo esc_html( $item['text'] ); ?></li>
					<?php endforeach; ?>
				</ul>
			<?php endif; ?>

			<table role="presentation" width="100%" cellspacing="0" cellpadding="0" style="margin-bottom:24px;">
				<tr>
					<td style="padding:12px;background:#f6f7f7;border-radius:4px;">
						<div style="font-size:12px;color:#646970;"><?php esc_html_e( 'Leads', 'dealroot' ); ?></div>
						<div style="font-size:24px;font-weight:600;"><?php echo esc_html( number_format_i18n( $current['leads'] ) ); ?></div>
						<div style="font-size:12px;color:<?php echo $delta >= 0 ? '#0b5a1f' : '#8a1f1f'; ?>;">
							<?php
							/* translators: %s: signed difference to the previous week, e.g. +3. */
							echo esc_html( sprintf( __( '%s vs. previous week', 'dealroot' ), ( $delta >= 0 ? '+' : '' ) . number_format_i18n( $delta ) ) );
							?>
						</div>
					</td>
					<td style="width:8px;"></td>
					<td style="padding:12px;background:#f6f7f7;border-radius:4px;">
						<div style="font-size:12px;color:#646970;"><?php esc_html_e( 'Won', 'dealroot' ); ?></div>
						<div style="font-size:24px;font-weight:600;"><?php echo esc_html( number_format_i18n( $current['won'] ) ); ?></div>
						<div style="font-size:12px;color:#646970;"><?php echo esc_html( Admin\Format::money_list( $current['revenue'] ) ); ?></div>
					</td>
					<?php if ( array_sum( $current['cost'] ) > 0 ) : ?>
						<td style="width:8px;"></td>
						<td style="padding:12px;background:#f6f7f7;border-radius:4px;">
							<div style="font-size:12px;color:#646970;"><?php esc_html_e( 'Ad spend', 'dealroot' ); ?></div>
							<div style="font-size:24px;font-weight:600;"><?php echo esc_html( Admin\Format::money_list( $current['cost'] ) ); ?></div>
							<div style="font-size:12px;color:#646970;">
								<?php
								/* translators: %s: return on ad spend, e.g. 3.2× */
								echo esc_html( sprintf( __( 'ROAS %s', 'dealroot' ), Admin\Format::roas( $current['revenue'], $current['cost'] ) ) );
								?>
							</div>
						</td>
					<?php elseif ( $clicks ) : ?>
						<td style="width:8px;"></td>
						<td style="padding:12px;background:#f6f7f7;border-radius:4px;">
							<div style="font-size:12px;color:#646970;"><?php esc_html_e( 'Contact clicks', 'dealroot' ); ?></div>
							<div style="font-size:24px;font-weight:600;"><?php echo esc_html( number_format_i18n( $clicks ) ); ?></div>
						</td>
					<?php endif; ?>
				</tr>
			</table>

			<?php if ( $data['channels'] ) : ?>
				<table role="presentation" width="100%" cellspacing="0" cellpadding="0" style="border-collapse:collapse;margin-bottom:24px;">
					<tr>
						<th align="left" style="<?php echo esc_attr( $cell ); ?>font-size:12px;color:#646970;font-weight:400;"><?php esc_html_e( 'Channel', 'dealroot' ); ?></th>
						<th align="right" style="<?php echo esc_attr( $cell ); ?>font-size:12px;color:#646970;font-weight:400;"><?php esc_html_e( 'Leads', 'dealroot' ); ?></th>
						<th align="right" style="<?php echo esc_attr( $cell ); ?>font-size:12px;color:#646970;font-weight:400;"><?php esc_html_e( 'Won', 'dealroot' ); ?></th>
						<?php if ( $clicks ) : ?>
							<th align="right" style="<?php echo esc_attr( $cell ); ?>font-size:12px;color:#646970;font-weight:400;"><?php esc_html_e( 'Contact clicks', 'dealroot' ); ?></th>
						<?php endif; ?>
					</tr>
					<?php foreach ( $data['channels'] as $channel => $row ) : ?>
						<tr>
							<td style="<?php echo esc_attr( $cell ); ?>"><?php echo esc_html( Attribution::channel_label( $channel ) ); ?></td>
							<td align="right" style="<?php echo esc_attr( $cell ); ?>"><?php echo esc_html( number_format_i18n( $row['leads'] ) ); ?></td>
							<td align="right" style="<?php echo esc_attr( $cell ); ?>"><?php echo esc_html( number_format_i18n( $row['won'] ) ); ?></td>
							<?php if ( $clicks ) : ?>
								<td align="right" style="<?php echo esc_attr( $cell ); ?>"><?php echo esc_html( number_format_i18n( (int) ( $row['clicks']['_total'] ?? 0 ) ) ); ?></td>
							<?php endif; ?>
						</tr>
					<?php endforeach; ?>
				</table>
			<?php endif; ?>

			<p>
				<a href="<?php echo esc_url( admin_url( 'admin.php?page=dealroot&period=7d' ) ); ?>" style="display:inline-block;background:#2271b1;color:#fff;text-decoration:none;padding:10px 16px;border-radius:4px;"><?php esc_html_e( 'Open your leads', 'dealroot' ); ?></a>
			</p>

			<p style="font-size:12px;color:#646970;margin-top:32px;">
				<?php esc_html_e( 'You receive this email because the weekly summary is turned on in Leads → Settings.', 'dealroot' ); ?>
			</p>
		</div>
		<?php
	}
}