<?php
/**
 * Activity log: one row per tool call.
 *
 * @package HandyMCP
 */

namespace HandyMCP\Tools;

use HandyMCP\Auth\Identity;
use HandyMCP\Database\Installer;
use HandyMCP\Support\Redactor;

defined( 'ABSPATH' ) || exit;

/**
 * Stores who called which tool, on what, and how it went. Write calls keep a
 * short, redacted copy of their arguments. Secrets are never stored.
 */
final class Log {

	/**
	 * Record a call.
	 *
	 * @param string                    $name     Tool name.
	 * @param array<string, mixed>|null $tool     Tool spec.
	 * @param Identity                  $identity Caller.
	 * @param string                    $status   success | error | denied.
	 * @param mixed                     $result   Result.
	 * @param array<string, mixed>      $args     Arguments.
	 * @param float                     $start    microtime at start.
	 */
	public function record( string $name, ?array $tool, Identity $identity, string $status, $result, array $args, float $start ): void {
		global $wpdb;
		$is_write = $tool ? (bool) $tool['write'] : false;
		$summary  = '';
		if ( is_array( $result ) && isset( $result['error']['message'] ) ) {
			$summary = (string) $result['error']['message'];
		} elseif ( is_array( $result ) && isset( $result['message'] ) && is_string( $result['message'] ) ) {
			$summary = $result['message'];
		}
		$ref = '';
		foreach ( array( 'post_id', 'id', 'product_id', 'order_id', 'form_id', 'template_id', 'element_id' ) as $key ) {
			if ( isset( $args[ $key ] ) && is_scalar( $args[ $key ] ) ) {
				$ref = $key . ':' . $args[ $key ];
				break;
			}
		}
		if ( '' === $ref && is_array( $result ) && isset( $result['id'] ) && is_scalar( $result['id'] ) ) {
			$ref = 'id:' . $result['id'];
		}
		$stored_args = '';
		if ( $is_write ) {
			$stored_args = (string) wp_json_encode( self::shorten( Redactor::redact( $args ) ) );
			if ( strlen( $stored_args ) > 4000 ) {
				$stored_args = substr( $stored_args, 0, 4000 ) . '...';
			}
		}
		try {
			$wpdb->insert( // phpcs:ignore WordPress.DB.DirectDatabaseQuery.DirectQuery
				Installer::table( 'log' ),
				array(
					'created_at'  => gmdate( 'Y-m-d H:i:s' ),
					'user_id'     => $identity->user_id,
					'client'      => mb_substr( (string) $identity->client, 0, 190 ),
					'auth_method' => $identity->method,
					'tool'        => mb_substr( $name, 0, 120 ),
					'tool_group'  => $tool ? (string) $tool['group'] : '',
					'is_write'    => $is_write ? 1 : 0,
					'status'      => $status,
					'object_ref'  => mb_substr( $ref, 0, 190 ),
					'summary'     => mb_substr( Redactor::scrub_string( $summary ), 0, 500 ),
					'args'        => $stored_args,
					'duration_ms' => (int) round( ( microtime( true ) - $start ) * 1000 ),
				)
			);
		} catch ( \Throwable $e ) {
			return; // Logging never breaks a tool call.
		}
	}

	/**
	 * Truncate long strings and big arrays so the log stays small.
	 *
	 * @param mixed $value Value.
	 * @param int   $depth Depth.
	 * @return mixed
	 */
	private static function shorten( $value, int $depth = 0 ) {
		if ( is_string( $value ) ) {
			return mb_strlen( $value ) > 300 ? mb_substr( $value, 0, 300 ) . '...(' . mb_strlen( $value ) . ' chars)' : $value;
		}
		if ( is_array( $value ) ) {
			if ( $depth > 3 ) {
				return '[' . count( $value ) . ' items]';
			}
			$out = array();
			$i   = 0;
			foreach ( $value as $k => $v ) {
				if ( ++$i > 25 ) {
					$out['...'] = ( count( $value ) - 25 ) . ' more';
					break;
				}
				$out[ $k ] = self::shorten( $v, $depth + 1 );
			}
			return $out;
		}
		return $value;
	}

	/**
	 * Recent entries.
	 *
	 * @param array<string, mixed> $filter status, tool, limit, offset.
	 * @return array{rows: array<int, object>, total: int}
	 */
	public function query( array $filter = array() ): array {
		global $wpdb;
		$t      = Installer::table( 'log' );
		$where  = array( '1=1' );
		$params = array();
		if ( ! empty( $filter['status'] ) ) {
			$where[]  = 'status = %s';
			$params[] = (string) $filter['status'];
		}
		if ( ! empty( $filter['writes'] ) ) {
			$where[] = 'is_write = 1';
		}
		$limit  = max( 1, min( 200, (int) ( $filter['limit'] ?? 50 ) ) );
		$offset = max( 0, (int) ( $filter['offset'] ?? 0 ) );
		$cond   = implode( ' AND ', $where );
		// phpcs:disable WordPress.DB.DirectDatabaseQuery.DirectQuery, WordPress.DB.DirectDatabaseQuery.NoCaching, WordPress.DB.PreparedSQL.InterpolatedNotPrepared, WordPress.DB.PreparedSQLPlaceholders.ReplacementsWrongNumber, PluginCheck.Security.DirectDB.UnescapedDBParameter -- custom table; $cond only joins fixed condition strings, values go through placeholders.
		$rows  = $wpdb->get_results( $wpdb->prepare( "SELECT * FROM %i WHERE {$cond} ORDER BY id DESC LIMIT %d OFFSET %d", array_merge( array( $t ), $params, array( $limit, $offset ) ) ) );
		$total = (int) $wpdb->get_var( $wpdb->prepare( "SELECT COUNT(*) FROM %i WHERE {$cond}", array_merge( array( $t ), $params ) ) );
		// phpcs:enable
		return array(
			'rows'  => is_array( $rows ) ? $rows : array(),
			'total' => $total,
		);
	}

	/**
	 * Counts for the last N days.
	 *
	 * @param int $days Days.
	 * @return array<string, int>
	 */
	public function stats( int $days = 7 ): array {
		global $wpdb;
		$t    = Installer::table( 'log' );
		$rows = $wpdb->get_results( $wpdb->prepare( 'SELECT status, is_write, COUNT(*) AS n FROM %i WHERE created_at > %s GROUP BY status, is_write', $t, gmdate( 'Y-m-d H:i:s', time() - $days * DAY_IN_SECONDS ) ) ); // phpcs:ignore WordPress.DB.DirectDatabaseQuery.DirectQuery, WordPress.DB.DirectDatabaseQuery.NoCaching -- custom table, stats must be current.
		$out  = array( 'calls' => 0, 'writes' => 0, 'errors' => 0 );
		foreach ( (array) $rows as $r ) {
			$out['calls'] += (int) $r->n;
			if ( (int) $r->is_write && 'success' === $r->status ) {
				$out['writes'] += (int) $r->n;
			}
			if ( 'error' === $r->status ) {
				$out['errors'] += (int) $r->n;
			}
		}
		return $out;
	}
}