<?php
/**
 * Install-wide settings: branding, email sender, alerts.
 *
 * @package TurtleReport
 */

namespace TurtleReport\Settings;

use TurtleReport\Support\OptionUpdate;

defined( 'ABSPATH' ) || exit;

/**
 * Reads and writes the single settings option, with defaults.
 */
final class Settings {

	const OPTION = 'turtlereport_settings';

	/**
	 * Request-level memo.
	 *
	 * @var array|null
	 */
	private $memo = null;

	/**
	 * Blog owning the memo.
	 *
	 * @var int
	 */
	private $memo_blog = 0;

	/**
	 * Default values.
	 *
	 * @return array
	 */
	public static function defaults() {
		return array(
			'brand_name'          => '',
			'brand_logo_id'       => 0,
			'brand_color'         => '#0f6b50',
			'footer_text'         => '',
			'hide_credit'         => true,
			'credit_opt_in'       => false,
			'email_from_name'     => '',
			'email_reply_to'      => '',
			'alerts_enabled'      => true,
			'alert_emails'        => array(),
			'alert_user_ids'      => array(),
			'email_defaults'      => array(
				'frequency' => 'monthly',
				'weekday'   => 1,
				'monthday'  => 3,
				'hour'      => 8,
				'compare'   => 'previous',
			),
			'warm_cache'          => true,
			'monitor_enabled'     => true,
			'monitor_sensitivity' => 'standard',
			'brief_enabled'       => false,
			'brief_weekday'       => 1,
			'brief_hour'          => 8,
			'brief_emails'        => array(),
			'ai_enabled'          => false,
			'ai_provider'         => 'openai',
			'ai_model'            => 'gpt-5-mini',
			'ai_daily_limit'      => 30,
			'ai_monthly_limit'    => 300,
			'ai_max_output'       => 1200,
			// Who confirmed that client data may go to which provider, and when.
			'ai_consent'          => array(),
		);
	}

	/**
	 * All settings merged over defaults.
	 *
	 * @return array
	 */
	public function all() {
		$blog = get_current_blog_id();
		if ( $blog !== $this->memo_blog ) {
			$this->memo      = null;
			$this->memo_blog = $blog;
		}
		if ( null === $this->memo ) {
			$stored     = get_option( self::OPTION, array() );
			$this->memo = array_merge( self::defaults(), is_array( $stored ) ? $stored : array() );
		}
		return $this->memo;
	}

	/**
	 * One setting.
	 *
	 * @param string $key Setting key.
	 * @return mixed
	 */
	public function get( $key ) {
		$all = $this->all();
		return array_key_exists( $key, $all ) ? $all[ $key ] : null;
	}

	/** Explicit permission to display credits in reports. @return bool */
	public function show_credit() {
		return true === $this->get( 'credit_opt_in' ) && ! $this->get( 'hide_credit' );
	}

	/**
	 * Saves settings. Unknown keys are dropped.
	 *
	 * @param array $values New values.
	 * @return void
	 */
	public function save( array $values ) {
		OptionUpdate::change(
			self::OPTION,
			static function ( array $current ) use ( $values ) {
				return array_intersect_key( array_merge( self::defaults(), $current, $values ), self::defaults() );
			}
		);
		$this->memo = null;
	}

	/**
	 * Brand name, falling back to the WordPress site title.
	 *
	 * @return string
	 */
	public function brand_name() {
		$name = (string) $this->get( 'brand_name' );
		return '' !== $name ? $name : (string) get_bloginfo( 'name' );
	}

	/**
	 * Brand colour as a validated hex value.
	 *
	 * @return string
	 */
	public function brand_color() {
		$color = (string) $this->get( 'brand_color' );
		return preg_match( '/^#[0-9a-fA-F]{6}$/', $color ) ? $color : '#0f6b50';
	}

	/**
	 * Brand logo URL, or an empty string.
	 *
	 * @return string
	 */
	public function logo_url() {
		return self::attachment_url( (int) $this->get( 'brand_logo_id' ) );
	}

	/**
	 * Schedule new sites start with (interval, day, time, comparison). Off until
	 * someone switches it on and picks recipients.
	 *
	 * @return array Normalised schedule.
	 */
	public function email_defaults() {
		$defaults = (array) $this->get( 'email_defaults' );
		return \TurtleReport\Policy\Schedule::normalize(
			array(
				'frequency' => isset( $defaults['frequency'] ) ? $defaults['frequency'] : 'monthly',
				'weekday'   => isset( $defaults['weekday'] ) ? $defaults['weekday'] : 1,
				'monthday'  => isset( $defaults['monthday'] ) ? $defaults['monthday'] : 3,
				'hour'      => isset( $defaults['hour'] ) ? $defaults['hour'] : 8,
				'compare'   => isset( $defaults['compare'] ) ? $defaults['compare'] : 'previous',
			)
		);
	}

	/**
	 * Addresses that receive connection alerts: the chosen users plus any typed
	 * addresses. Falls back to the site admin email when nobody is chosen.
	 *
	 * @return string[]
	 */
	public function alert_recipients() {
		$list = array();
		foreach ( (array) $this->get( 'alert_user_ids' ) as $user_id ) {
			$user = get_userdata( (int) $user_id );
			if ( $user && is_email( $user->user_email ) ) {
				$list[] = (string) $user->user_email;
			}
		}
		$list = array_merge( $list, array_filter( (array) $this->get( 'alert_emails' ), 'is_email' ) );
		$list = array_values( array_unique( array_map( 'strtolower', $list ) ) );
		return $list ? $list : array( (string) get_option( 'admin_email' ) );
	}

	/**
	 * Local file of an image attachment (the medium size when there is one), for
	 * server-made PDFs. Empty when it isn't an image or isn't stored locally
	 * (for example on an offloaded media library).
	 *
	 * @param int $id Attachment ID.
	 * @return string
	 */
	public static function attachment_file( $id ) {
		$id = (int) $id;
		if ( $id <= 0 || ! function_exists( 'get_attached_file' ) || ! wp_attachment_is_image( $id ) ) {
			return '';
		}
		$full = (string) get_attached_file( $id );
		if ( function_exists( 'image_get_intermediate_size' ) ) {
			$medium = image_get_intermediate_size( $id, 'medium' );
			if ( is_array( $medium ) && ! empty( $medium['path'] ) ) {
				$uploads = wp_upload_dir( null, false );
				$path    = trailingslashit( $uploads['basedir'] ) . $medium['path'];
				if ( is_readable( $path ) ) {
					return $path;
				}
			}
		}
		return '' !== $full && is_readable( $full ) ? $full : '';
	}

	/**
	 * URL of an image attachment, or an empty string.
	 *
	 * @param int $id Attachment ID.
	 * @return string
	 */
	public static function attachment_url( $id ) {
		if ( $id <= 0 || ! wp_attachment_is_image( $id ) ) {
			return '';
		}
		$src = wp_get_attachment_image_src( $id, 'medium' );
		return $src ? (string) $src[0] : '';
	}
}