From 38095f0972b82e8181fc4f3a06dc0db621811be0 Mon Sep 17 00:00:00 2001
From: fowr <89118232+perdedora@users.noreply.github.com>
Date: Thu, 10 Apr 2025 11:58:35 -0300
Subject: [PATCH] FloodService.php: add flood service for flood detection logic

---
 inc/Service/FloodService.php | 133 +++++++++++++++++++++++++++++++++++
 1 file changed, 133 insertions(+)
 create mode 100644 inc/Service/FloodService.php

diff --git a/inc/Service/FloodService.php b/inc/Service/FloodService.php
new file mode 100644
index 00000000..9e803684
--- /dev/null
+++ b/inc/Service/FloodService.php
@@ -0,0 +1,133 @@
+<?php
+
+namespace Vichan\Service;
+
+use Vichan\Data\FloodQueries;
+
+/**
+ * Manages post flood detection logic based on recent post history.
+ * Uses filter configurations to determine relevant time windows.
+ */
+class FloodService {
+	/**
+	 * @var FloodQueries Handles database interactions for flood data.
+	 */
+	private FloodQueries $floodQueries;
+
+	/**
+	 * @var array<int, array<string, mixed>> Filter configurations.
+	 */
+	private array $filters;
+
+	/**
+	 * @var int Cache for the calculated maximum flood time (-1 means not calculated).
+	 */
+	private int $flood_cache;
+
+	/**
+	 * Constructor for FloodService.
+	 *
+	 * @param FloodQueries $floodQueries The database query handler for flood data.
+	 * @param array<int, array<string, mixed>> $filters Filter configurations.
+	 * @param int $flood_cache Optional pre-calculated max flood time.
+	 */
+	public function __construct(FloodQueries $floodQueries, array $filters, int $flood_cache = -1) {
+		$this->floodQueries = $floodQueries;
+		$this->filters = $filters;
+		$this->flood_cache = $flood_cache;
+	}
+
+	/**
+	 * Calculates or retrieves the maximum flood time window from filters.
+	 *
+	 * @return int The maximum 'flood-time' value found in filters, or 0 if none.
+	 */
+	public function getMaxFloodTime(): int {
+		if (isset($this->flood_cache) && $this->flood_cache !== -1) {
+			return $this->flood_cache;
+		}
+
+		$maxTime = 0;
+		foreach ($this->filters as $filter) {
+			if (isset($filter['condition']['flood-time']) && $filter['condition']['flood-time'] > $maxTime) {
+				$maxTime = $filter['condition']['flood-time'];
+			}
+		}
+		$this->flood_cache = $maxTime;
+
+		return $maxTime;
+	}
+
+	/**
+	 * Removes flood entries older than the maximum relevant flood time.
+	*/
+	public function purgeOldEntries(): void {
+		$maxTime = $this->getMaxFloodTime();
+
+		if ($maxTime > 0) {
+			$this->floodQueries->purgeOldEntries($maxTime);
+		}
+	}
+
+	/**
+	 * Retrieves recent flood entries relevant to the given post's IP, body hash, or file hash.
+	 *
+	 * @param array<string, mixed> $post The post data array. Expects 'ip', 'body_nomarkup', optionally 'filehash', 'has_file'.
+	 * @return array<int, array<string, mixed>> List of matching flood entries.
+	 */
+	public function getFloodEntries(array $post): array {
+		$bodyHash = \make_comment_hex($post['body_nomarkup'] ?? '');
+		$fileHash = isset($post['has_file']) && $post['has_file'] ? $post['filehash'] : null;
+
+		return $this->floodQueries->getRecentFloodEntries($post['ip'], $bodyHash, $fileHash);
+	}
+
+	/**
+	 * Compares a specific field between a historical flood entry and the current post.
+	 *
+	 * Valid conditions: 'ip', 'body', 'file', 'board', 'isreply'.
+	 *
+	 * @param string $condition The condition to check.
+	 * @param array<string, mixed> $floodPost A single historical flood entry.
+	 * @param array<string, mixed> $post The current post data.
+	 * @return bool True if the condition matches between the two posts.
+	 * @throws \InvalidArgumentException If the condition string is not recognized.
+	 */
+	public function checkFloodCondition(string $condition, array $floodPost, array $post): bool {
+		switch ($condition) {
+			case 'ip':
+				return isset($floodPost['ip'], $post['ip']) && $floodPost['ip'] === $post['ip'];
+			case 'body':
+				$currentBodyHash = \make_comment_hex($post['body_nomarkup'] ?? '');
+				return isset($floodPost['posthash']) && $floodPost['posthash'] === $currentBodyHash;
+			case 'file':
+				$hasFile = $post['has_file'] ?? false;
+				$currentFileHash = ($hasFile && isset($post['filehash'])) ? $post['filehash'] : null;
+				return isset($floodPost['filehash']) && $currentFileHash !== null && $floodPost['filehash'] === $currentFileHash;
+			case 'board':
+				return isset($floodPost['board'], $post['board']) && $floodPost['board'] === $post['board'];
+			case 'isreply':
+				$currentIsReply = isset($post['thread']);
+				return isset($floodPost['isreply']) && (bool)$floodPost['isreply'] === $currentIsReply;
+			default:
+				throw new \InvalidArgumentException('Invalid filter flood condition: ' . $condition);
+		}
+	}
+
+	/**
+	 * Records a new entry in the flood table for the given post.
+	 *
+	 * @param array<string, mixed> $post The post data array. Expects 'ip', 'body_nomarkup', 'board', 'thread' optionally 'filehash', 'has_file'.
+	 */
+	public function recordFloodEntry(array $post): void {
+		$this->floodQueries->addFloodEntry(
+			$post['ip'],
+			\make_comment_hex($post['body_nomarkup'] ?? ''),
+			isset($post['has_file']) && $post['has_file'] ? $post['filehash'] : null,
+			$post['board'],
+			\time(),
+			isset($post['thread'])
+		);
+	}
+
+}