namespace MCPForUnity.Editor.Services.Server
{
/// <summary>
/// Interface for managing PID files and handshake state for the local HTTP server.
/// Handles persistence of server process information across Unity domain reloads.
/// </summary>
public interface IPidFileManager
{
/// <summary>
/// Gets the directory where PID files are stored.
/// </summary>
/// <returns>Path to the PID file directory</returns>
string GetPidDirectory();
/// <summary>
/// Gets the path to the PID file for a specific port.
/// </summary>
/// <param name="port">The port number</param>
/// <returns>Full path to the PID file</returns>
string GetPidFilePath(int port);
/// <summary>
/// Attempts to read the PID from a PID file.
/// </summary>
/// <param name="pidFilePath">Path to the PID file</param>
/// <param name="pid">Output: the process ID if found</param>
/// <returns>True if a valid PID was read</returns>
bool TryReadPid(string pidFilePath, out int pid);
/// <summary>
/// Attempts to extract the port number from a PID file path.
/// </summary>
/// <param name="pidFilePath">Path to the PID file</param>
/// <param name="port">Output: the port number</param>
/// <returns>True if the port was extracted successfully</returns>
bool TryGetPortFromPidFilePath(string pidFilePath, out int port);
/// <summary>
/// Deletes a PID file.
/// </summary>
/// <param name="pidFilePath">Path to the PID file to delete</param>
void DeletePidFile(string pidFilePath);
/// <summary>
/// Stores the handshake information (PID file path and instance token) in EditorPrefs.
/// </summary>
/// <param name="pidFilePath">Path to the PID file</param>
/// <param name="instanceToken">Unique instance token for the server</param>
void StoreHandshake(string pidFilePath, string instanceToken);
/// <summary>
/// Attempts to retrieve stored handshake information from EditorPrefs.
/// </summary>
/// <param name="pidFilePath">Output: stored PID file path</param>
/// <param name="instanceToken">Output: stored instance token</param>
/// <returns>True if valid handshake information was found</returns>
bool TryGetHandshake(out string pidFilePath, out string instanceToken);
/// <summary>
/// Stores PID tracking information in EditorPrefs.
/// </summary>
/// <param name="pid">The process ID</param>
/// <param name="port">The port number</param>
/// <param name="argsHash">Optional hash of the command arguments</param>
void StoreTracking(int pid, int port, string argsHash = null);
/// <summary>
/// Attempts to retrieve a stored PID for the expected port.
/// Validates that the stored information is still valid (within 6-hour window).
/// </summary>
/// <param name="expectedPort">The expected port number</param>
/// <param name="pid">Output: the stored process ID</param>
/// <returns>True if a valid stored PID was found</returns>
bool TryGetStoredPid(int expectedPort, out int pid);
/// <summary>
/// Gets the stored args hash for the tracked server.
/// </summary>
/// <returns>The stored args hash, or empty string if not found</returns>
string GetStoredArgsHash();
/// <summary>
/// Clears all PID tracking information from EditorPrefs.
/// </summary>
void ClearTracking();
/// <summary>
/// Computes a short hash of the input string for fingerprinting.
/// </summary>
/// <param name="input">The input string</param>
/// <returns>A short hash string (16 hex characters)</returns>
string ComputeShortHash(string input);
}
}
