<?php

if ( ! defined( 'ABSPATH' ) ) {
	exit;
}

class Argus_Events {

	const DEFAULT_MAX_ROWS = 50000;

	public static function record( $type, $severity, $summary, array $payload = array(), $ip = null ) {
		global $wpdb;

		$wpdb->insert(
			Argus_DB::table( 'events' ),
			array(
				'event_type' => $type,
				'severity'   => $severity,
				'ip'         => $ip,
				'summary'    => $summary,
				'payload'    => wp_json_encode( $payload ),
				'created_at' => current_time( 'mysql', true ),
			),
			array( '%s', '%s', '%s', '%s', '%s', '%s' )
		);

		return (int) $wpdb->insert_id;
	}

	public static function recent( $limit = 50, $type = null ) {
		global $wpdb;
		$table = Argus_DB::table( 'events' );

		if ( $type ) {
			$rows = $wpdb->get_results(
				$wpdb->prepare( "SELECT * FROM {$table} WHERE event_type = %s ORDER BY created_at DESC LIMIT %d", $type, $limit ) // phpcs:ignore
			);
		} else {
			$rows = $wpdb->get_results(
				$wpdb->prepare( "SELECT * FROM {$table} ORDER BY created_at DESC LIMIT %d", $limit ) // phpcs:ignore
			);
		}

		foreach ( $rows as &$row ) {
			$row->payload = json_decode( $row->payload, true );
		}

		return $rows;
	}

	public static function counts_since( $since_mysql ) {
		global $wpdb;
		$table = Argus_DB::table( 'events' );

		return $wpdb->get_results(
			$wpdb->prepare(
				"SELECT event_type, severity, COUNT(*) AS cnt FROM {$table} WHERE created_at >= %s GROUP BY event_type, severity", // phpcs:ignore
				$since_mysql
			)
		);
	}

	const PER_PAGE = 10;

	public static function paginated( $page = 1, array $filters = array(), $per_page = self::PER_PAGE ) {
		global $wpdb;
		$table  = Argus_DB::table( 'events' );
		$page   = max( 1, (int) $page );
		$offset = ( $page - 1 ) * $per_page;

		$where  = array( '1=1' );
		$args   = array();

		if ( ! empty( $filters['search'] ) ) {
			$where[] = 'summary LIKE %s';
			$args[]  = '%' . $wpdb->esc_like( $filters['search'] ) . '%';
		}
		if ( ! empty( $filters['severity'] ) ) {
			$where[] = 'severity = %s';
			$args[]  = $filters['severity'];
		}
		if ( ! empty( $filters['type'] ) ) {
			$where[] = 'event_type = %s';
			$args[]  = $filters['type'];
		}
		if ( ! empty( $filters['since'] ) ) {
			$where[] = 'created_at >= %s';
			$args[]  = $filters['since'];
		}

		$where_sql = implode( ' AND ', $where );

		$count_sql = "SELECT COUNT(*) FROM {$table} WHERE {$where_sql}"; // phpcs:ignore
		$total     = (int) ( $args ? $wpdb->get_var( $wpdb->prepare( $count_sql, $args ) ) : $wpdb->get_var( $count_sql ) ); // phpcs:ignore

		$list_sql  = "SELECT * FROM {$table} WHERE {$where_sql} ORDER BY created_at DESC LIMIT %d OFFSET %d"; // phpcs:ignore
		$list_args = array_merge( $args, array( $per_page, $offset ) );
		$rows      = $wpdb->get_results( $wpdb->prepare( $list_sql, $list_args ) ); // phpcs:ignore

		foreach ( $rows as &$row ) {
			$row->payload = json_decode( $row->payload, true );
		}

		return array(
			'rows'        => $rows,
			'total'       => $total,
			'total_pages' => max( 1, (int) ceil( $total / $per_page ) ),
			'page'        => $page,
		);
	}

	public static function distinct_types() {
		global $wpdb;
		$table = Argus_DB::table( 'events' );
		return $wpdb->get_col( "SELECT DISTINCT event_type FROM {$table} ORDER BY event_type ASC" ); // phpcs:ignore
	}

	const RETENTION_DAYS_BY_SEVERITY = array(
		'info'     => 30,
		'low'      => 90,
		'medium'   => 365,
		'high'     => 365,
		'critical' => 365,
	);

	public static function prune() {
		global $wpdb;
		$table = Argus_DB::table( 'events' );

		$retention = apply_filters( 'argus_wpd_event_retention_days', self::RETENTION_DAYS_BY_SEVERITY );
		$deleted   = 0;
		foreach ( $retention as $severity => $days ) {
			$cutoff   = gmdate( 'Y-m-d H:i:s', time() - ( (int) $days * DAY_IN_SECONDS ) );
			$deleted += (int) $wpdb->query(
				$wpdb->prepare( "DELETE FROM {$table} WHERE severity = %s AND created_at < %s", $severity, $cutoff ) // phpcs:ignore
			);
		}

		$max_rows = (int) apply_filters( 'argus_wpd_max_event_rows', self::DEFAULT_MAX_ROWS );
		$total    = (int) $wpdb->get_var( "SELECT COUNT(*) FROM {$table}" ); // phpcs:ignore
		if ( $total <= $max_rows ) {
			return $deleted;
		}

		$overflow = $total - $max_rows;
		$deleted += (int) $wpdb->query(
			$wpdb->prepare(
				"DELETE FROM {$table} ORDER BY created_at ASC LIMIT %d", // phpcs:ignore
				$overflow
			)
		);

		return $deleted;
	}
}