**Purpose:** Initializes the Http object and sets up HTTP session handling.
**Parameters:**
  - ##$db## - Database object reference
**Initialization Steps:**
  1. Stores database reference
  2. Extracts and normalizes REQUEST_URI
  3. Detects TLS/HTTPS session status
  4. Determines client's real IP address
  5. Sets up TLS mark cookie name
  6. Enforces TLS session upgrade if needed
**Example:**

==== Caching System ====
===== ##check_cache($page, $method): void## =====
Determines if a page can be cached and prepares the cache check.
**Parameters:**
  - ##$page## (string) - Page name to cache
  - ##$method## (string) - Request method/action (e.g., 'show', 'edit')
**Caching Rules:**
  - ✅ Enabled for GET requests only
  - ✅ Disabled for POST requests
  - ❌ Never cached for 'edit' or 'watch' methods
  - ✅ Only cached for anonymous users (no logged-in users)
**Example:**

===== ##invalidate_page($page): int## =====
Invalidates all cached versions of a page.
**Parameters:**
  - ##$page## (string) - Page name to invalidate
**Returns:**
  - Number of cache entries invalidated
**Process:**
  1. Finds all cached versions (different methods/languages)
  2. Touches files to past timestamp (faster than deletion)
  3. Removes entries from cache metadata table
  4. Returns count of invalidated caches
**Example:**

===== ##ensure_tls($url): void## =====
Enforces HTTPS for a specific URL and redirects if necessary.
**Parameters:**
  - ##$url## (string) - URL to secure
**Behavior:**
  - If not already HTTPS and TLS is enabled, forces HTTPS redirect
  - Handles both relative and absolute URLs
  - Converts relative URLs using current server name
**Example:**

==== HTTPS Detection ====
===== ##tls_session(): bool## (Private) =====
Detects if current connection uses HTTPS/TLS.
**Checks (any being true = HTTPS):**
  - ##$_SERVER['HTTPS']## is 'on'
  - ##$_SERVER['SERVER_PORT']## is 443
  - ##$_SERVER['HTTP_X_FORWARDED_PROTO']## is 'https'
  - ##$_SERVER['HTTP_X_FORWARDED_SSL']## is 'on'
  - ##$_SERVER['HTTP_X_FORWARDED_PORT']## is 443
==== Security Headers ====
=====##http_security_headers(): void##=====
Sets security-related HTTP headers.
**Headers Set:**
*| Header | Purpose | Config Key |*
**CSP Configuration Options:**
  - ##0## - Disabled
  - ##1## - Default policy (from ##csp.conf##)
  - ##2## - Custom policy (from ##csp_custom.conf##)
**Example:**

===== ##terminate(): void## =====
Safe exit/die with cleanup.
**Cleanup Operations:**
  - Saves diagnostic logs to session flash data
  - Ends script execution
**Example:**

**Example:**

===== ##cache_promisc(): void## =====
Marks page as publicly cacheable.
**Headers Set:**
  - ##Cache-Control: public##
**Example:**

==== File Serving ====
===== ##sendfile($path, $filename = null, $age = null): void## =====
Serves files with proper HTTP headers and caching.
**Parameters:**
  - ##$path## (string) - File path (or HTTP_XXX constant for error pages)
  - ##$filename## (string, optional) - Custom download filename
  - ##$age## (int, optional) - Cache age in days
**Features:**
  - HTTP range request support (partial file downloads)
  - ETag and Last-Modified conditional requests
  - Proper MIME type detection
  - Content-Security-Policy for special file types
  - Streaming for large files
  - GZip compression for text files
**Special Paths:**

===== ##mime_type($path): string## =====
Returns MIME type for a file.
**Returns:**
  - MIME type string (e.g., 'application/pdf')
  - Default: ##'application/octet-stream'##
**Example:**

==== Utility Methods ====
===== ##parse_str($str): array## (Private) =====
Parses URL-encoded strings with special character handling.
**Purpose:**
  - Safely handles special characters in query/form data
  - Converts encoding properly
**Example:**

HTTP Class Technical Documentation

Public Properties

|| ==== Private Properties ==== ||
|| Property | Type | Description ||
|| ---------- | ------ | ------------- ||
|| ---- ||
|| === Constructor === ||
||

php	

||
|| **Purpose:** Initializes the Http object and sets up HTTP session handling. ||
|| **Parameters:** ||
|| - ##$db## - Database object reference ||
|| **Initialization Steps:** ||
|| 1. Stores database reference ||
|| 2. Extracts and normalizes REQUEST_URI ||
|| 3. Detects TLS/HTTPS session status ||
|| 4. Determines client's real IP address ||
|| 5. Sets up TLS mark cookie name ||
|| 6. Enforces TLS session upgrade if needed ||
|| **Example:** ||
||

php	

||
|| ---- ||
|| === Core Methods === ||
|| ==== Session Management ==== ||
|| ===== ##session($route): void## ===== ||
|| Initializes the session handler (file-based or database-based). ||
|| **Parameters:** ||
|| - ##$route## (int) - Routing flag: ||
|| - Bit 2 (##$route & 2##): Enable static mode for files/freecap (disables replay prevention and ID regeneration) ||
|| **Features:** ||
|| - Selects storage backend (file or database) ||
|| - Configures cookie settings (security, path, httponly) ||
|| - Binds IP and TLS validation ||
|| - Recovers diagnostic logs from previous session ||
|| **Example:** ||
||

php	

||
|| ---- ||
|| ==== Caching System ==== ||
|| ===== ##check_cache($page, $method): void## ===== ||
|| Determines if a page can be cached and prepares the cache check. ||
|| **Parameters:** ||
|| - ##$page## (string) - Page name to cache ||
|| - ##$method## (string) - Request method/action (e.g., 'show', 'edit') ||
|| **Caching Rules:** ||
|| - ✅ Enabled for GET requests only ||
|| - ✅ Disabled for POST requests ||
|| - ❌ Never cached for 'edit' or 'watch' methods ||
|| - ✅ Only cached for anonymous users (no logged-in users) ||
|| **Example:** ||
||

php	

||
|| ---- ||
|| ===== ##store_cache(): void## ===== ||
|| Saves the generated page content to cache file. ||
|| **Features:** ||
|| - Retrieves output buffer content ||
|| - Saves to cache file with proper permissions ||
|| - Records cache metadata in database ||
|| - Only executes if caching flag is set and user is anonymous ||
|| **Example:** ||
||

php	

||
|| ---- ||
|| ===== ##invalidate_page($page): int## ===== ||
|| Invalidates all cached versions of a page. ||
|| **Parameters:** ||
|| - ##$page## (string) - Page name to invalidate ||
|| **Returns:** ||
|| - Number of cache entries invalidated ||
|| **Process:** ||
|| 1. Finds all cached versions (different methods/languages) ||
|| 2. Touches files to past timestamp (faster than deletion) ||
|| 3. Removes entries from cache metadata table ||
|| 4. Returns count of invalidated caches ||
|| **Example:** ||
||

php	

||
|| ---- ||
|| ==== TLS/HTTPS Security ==== ||
|| ===== ##secure_base_url(): void## ===== ||
|| Switches base URL from HTTP to HTTPS. ||
|| **Purpose:** ||
|| - Ensures all subsequent URLs use HTTPS ||
|| - Stores original HTTP URL for fallback ||
|| - Called when TLS session is detected ||
|| **Example:** ||
||

php	

||
|| ---- ||
|| ===== ##ensure_tls($url): void## ===== ||
|| Enforces HTTPS for a specific URL and redirects if necessary. ||
|| **Parameters:** ||
|| - ##$url## (string) - URL to secure ||
|| **Behavior:** ||
|| - If not already HTTPS and TLS is enabled, forces HTTPS redirect ||
|| - Handles both relative and absolute URLs ||
|| - Converts relative URLs using current server name ||
|| **Example:** ||
||

php	

||
|| ---- ||
|| ==== IP Address Detection ==== ||
|| ===== ##real_ip(): string## (Private) ===== ||
|| Detects client's real IP address accounting for proxies. ||
|| **Proxy Headers Checked (in order):** ||
|| 1. ##HTTP_X_CLUSTER_CLIENT_IP## ||
|| 2. ##HTTP_X_FORWARDED_FOR## (or custom header) ||
|| 3. ##HTTP_CLIENT_IP## ||
|| 4. ##HTTP_X_REMOTE_ADDR## ||
|| 5. ##REMOTE_ADDR## (fallback) ||
|| **Features:** ||
|| - Filters out private/reserved IP ranges ||
|| - Respects configured reverse proxy addresses ||
|| - Returns ##'0.0.0.0'## as fallback ||
|| **Configuration in Database:** ||
|| - ##reverse_proxy_addresses## - Comma/space-separated proxy IPs ||
|| - ##reverse_proxy_header## - Custom header name (default: ##X-Forwarded-For##) ||
|| **Example:** ||
||

php	

||
|| ---- ||
|| ==== HTTPS Detection ==== ||
|| ===== ##tls_session(): bool## (Private) ===== ||
|| Detects if current connection uses HTTPS/TLS. ||
|| **Checks (any being true = HTTPS):** ||
|| - ##$_SERVER['HTTPS']## is 'on' ||
|| - ##$_SERVER['SERVER_PORT']## is 443 ||
|| - ##$_SERVER['HTTP_X_FORWARDED_PROTO']## is 'https' ||
|| - ##$_SERVER['HTTP_X_FORWARDED_SSL']## is 'on' ||
|| - ##$_SERVER['HTTP_X_FORWARDED_PORT']## is 443 ||
|| ---- ||
|| ==== Security Headers ==== ||
|| ===== ##http_security_headers(): void## ===== ||
|| Sets security-related HTTP headers. ||
|| **Headers Set:** ||
|| Header | Purpose | Config Key ||
|| -------- | --------- | ------------ ||
|| **CSP Configuration Options:** ||
|| - ##0## - Disabled ||
|| - ##1## - Default policy (from ##csp.conf##) ||
|| - ##2## - Custom policy (from ##csp_custom.conf##) ||
|| **Example:** ||
||

php	

||
|| ---- ||
|| ==== HTTP Methods ==== ||
|| ===== ##redirect($url, $permanent = false): void## ===== ||
|| Performs an HTTP redirect. ||
|| **Parameters:** ||
|| - ##$url## (string) - Target URL ||
|| - ##$permanent## (bool) - Use 301 (permanent) vs 302 (temporary) ||
|| **Features:** ||
|| - Decodes ##&## entities to prevent broken redirects ||
|| - Only works if headers not yet sent ||
|| - Uses output buffering to work anywhere in page processing ||
|| **Example:** ||
||

php	

||
|| ---- ||
|| ===== ##terminate(): void## ===== ||
|| Safe exit/die with cleanup. ||
|| **Cleanup Operations:** ||
|| - Saves diagnostic logs to session flash data ||
|| - Ends script execution ||
|| **Example:** ||
||

php	

||
|| ---- ||
|| ===== ##status($code): void## ===== ||
|| Sets HTTP response status code. ||
|| **Supported Status Codes:** ||
||

php	

||
|| **Example:** ||
||

php	

||
|| ---- ||
|| ==== Caching Control ==== ||
|| ===== ##no_cache($client_only = true): void## ===== ||
|| Disables caching of the current page. ||
|| **Parameters:** ||
|| - ##$client_only## (bool, default: TRUE) ||
|| - ##TRUE##: Disable browser cache only ||
|| - ##FALSE##: Disable both browser and server cache ||
|| **Headers Set:** ||
|| - ##Last-Modified: <current-time>## (always fresh) ||
|| - ##Cache-Control: no-store## ||
|| **Example:** ||
||

php	

||
|| ---- ||
|| ===== ##cache_promisc(): void## ===== ||
|| Marks page as publicly cacheable. ||
|| **Headers Set:** ||
|| - ##Cache-Control: public## ||
|| **Example:** ||
||

php	

||
|| ---- ||
|| ==== Language Negotiation ==== ||
|| ===== ##user_agent_language(): string## ===== ||
|| Determines best language based on browser preferences. ||
|| **Features:** ||
|| - Follows RFC 9110 section 12.5.4 (HTTP Accept-Language) ||
|| - Parses ##Accept-Language## header with quality factors ||
|| - Attempts exact match first, then language fallback ||
|| - Falls back to default system language ||
|| **Example Header:** ||
||

||
|| **Returns:** ||
|| - Language code (e.g., 'en', 'en-US', 'de') ||
|| ---- ||
|| ===== ##available_languages($subset = true): array## ===== ||
|| Returns list of available language translations. ||
|| **Parameters:** ||
|| - ##$subset## (bool, default: TRUE) ||
|| - ##TRUE##: Only allowed languages ||
|| - ##FALSE##: All available languages ||
|| **Features:** ||
|| - Scans ##LANG_DIR## for language files ||
|| - Filters by ##allowed_languages## config if set ||
|| - Caches result in session ||
|| - System language always included ||
|| **Returns:** ||
|| - Associative array: ##['en' => 'en', 'de' => 'de', ...]## ||
|| **Example:** ||
||

php	

||
|| ---- ||
|| ==== File Serving ==== ||
|| ===== ##sendfile($path, $filename = null, $age = null): void## ===== ||
|| Serves files with proper HTTP headers and caching. ||
|| **Parameters:** ||
|| - ##$path## (string) - File path (or HTTP_XXX constant for error pages) ||
|| - ##$filename## (string, optional) - Custom download filename ||
|| - ##$age## (int, optional) - Cache age in days ||
|| **Features:** ||
|| - HTTP range request support (partial file downloads) ||
|| - ETag and Last-Modified conditional requests ||
|| - Proper MIME type detection ||
|| - Content-Security-Policy for special file types ||
|| - Streaming for large files ||
|| - GZip compression for text files ||
|| **Special Paths:** ||
||

php	

||
|| **Example:** ||
||

php	

||
|| ---- ||
|| ===== ##mime_type($path): string## ===== ||
|| Returns MIME type for a file. ||
|| **Returns:** ||
|| - MIME type string (e.g., 'application/pdf') ||
|| - Default: ##'application/octet-stream'## ||
|| **Example:** ||
||

php	

||
|| ---- ||
|| ===== ##mime_types(): array## (Private) ===== ||
|| Loads and caches MIME types from configuration. ||
|| **Features:** ||
|| - Reads from ##config/mime.types## ||
|| - Caches to ##cache/config/mime.types## ||
|| - Reloads if config is updated ||
|| ---- ||
|| ==== Compression ==== ||
|| ===== ##gzip(): void## ===== ||
|| Compresses HTTP response with gzip/x-gzip. ||
|| **Features:** ||
|| - Manually implements gzip (not relying on zlib.output_compression) ||
|| - Produces correct ##Content-Length## header ||
|| - Only compresses if: ||
|| - 860 bytes < content < 1 MB ||
|| - Client accepts compression ||
|| - Headers not already sent ||
|| **Example:** ||
||

php	

||
|| ---- ||
|| ==== Utility Methods ==== ||
|| ===== ##parse_str($str): array## (Private) ===== ||
|| Parses URL-encoded strings with special character handling. ||
|| **Purpose:** ||
|| - Safely handles special characters in query/form data ||
|| - Converts encoding properly ||
|| **Example:** ||
||

php	

||
|| ---- ||
|| ===== ##request_uri(): string## (Private) ===== ||
|| Extracts and normalizes REQUEST_URI from server. ||
|| **Normalization:** ||
|| - Removes base URL prefix ||
|| - Removes spaces ||
|| - Collapses multiple slashes ||
|| - Removes ##..## path traversal attempts ||
|| - Removes leading/trailing slashes ||
|| ---- ||
|| ===== ##cut_prefix($prefix, $path): string## (Private) ===== ||
|| Removes prefix from path (case-insensitive). ||
|| ---- ||
|| ===== ##get_header_conf($file_name): string## (Private) ===== ||
|| Loads security header configuration from files. ||
|| **Files Supported:** ||
|| - ##csp.conf## / ##csp_custom.conf## ||
|| - ##permissions_policy.conf## / ##permissions_policy_custom.conf## ||
|| ---- ||
|| === Configuration Dependencies === ||
|| The class relies on these database configuration settings: ||
|| Setting | Type | Purpose ||
|| --------- | ------ | --------- ||
|| ---- ||
|| === Constants Used === ||
|| Constant | Type | Purpose ||
|| ---------- | ------ | --------- ||

Example 1: Handling a GET Request

php	

php

php	

php
%%php