// /file SNFMilterConfig.cpp
//
// Copyright (C) 2011, ARM Research Labs, LLC.
// See www.armresearch.com for the copyright terms.
//
// This file contains the functions for SNFMilterConfig.
//
// $Id$
//
///////////////////////////////////////////////////////////////////////////////////////////////////

#include <errno.h>
#include <string.h>
#include <unistd.h>
#include <sys/types.h>
#include <pwd.h>

#include <sys/types.h>
#include <sys/stat.h>
#include <unistd.h>

#include <exception>
#include <stdexcept>
#include <sstream>
#include <iostream>
#include <fstream>
#include <vector>
#include "SNFMilterConfig.hpp"

using namespace std;

//////////////////////////////////////////////////////////////////////////////////////////////////////////
// Configuration. ////////////////////////////////////////////////////////////////////////////////////////
//////////////////////////////////////////////////////////////////////////////////////////////////////////

// Initialize default configuration file path.
#ifdef WIN

//  Windows OS.
const std::string SNFMilterConfig::DefaultConfigFile("C:\\SNF\\SNFMilter.xml");
const std::string SNFMilterConfig::DefaultSampleConfigFile("C:\\SNF\\SNFMilter.xml.sample");

#else

#ifdef DEFAULT_CONFIG_DIR
//  *nix, DEFAULT_CONFIG_DIR is specified on the compile command line.
const std::string SNFMilterConfig::DefaultConfigFile(DEFAULT_CONFIG_DIR "/snf-milter/SNFMilter.xml");
const std::string SNFMilterConfig::DefaultSampleConfigFile(DEFAULT_CONFIG_DIR "/snf-milter/SNFMilter.xml.sample");
#else
// Not Windows, and DEFAULT_CONFIG_DIR is not specified on the compile
// command line.  In this case, we don't know the default path for the
// configuration file.
const std::string SNFMilterConfig::DefaultConfigFile("");
const std::string SNFMilterConfig::DefaultSampleConfigFile("");
#endif

#endif

const string ConfigFileKey("-config=");
const string IntegrateWithNoneKey("-mta=none");
const string IntegrateWithPostfixKey("-mta=postfix");
const string IntegrateWithSendmailKey("-mta=sendmail");

const string SnfMilterMainCfSearchString("Added by SNFMilterConfig");

const string SnfMilterMainCfIntegrationString("smtpd_milters = unix:/var/snf-milter/socket $smtpd_milters # Added by SNFMilterConfig");

//////////////////////////////////////////////////////////////////////////////////////////////////////////
// End of configuration. /////////////////////////////////////////////////////////////////////////////////
//////////////////////////////////////////////////////////////////////////////////////////////////////////

void
SNFMilterConfig::DisplayHelp(std::string Version) {

    cout
      << Version << endl
      << "Copyright (C) 2012, ARM Research Labs, LLC (www.armresearch.com)\n\n"
      << "Usage:\n\n"
      << "SNFMilterConfig [" << ConfigFileKey << "snf-config-file] "
      << IntegrateWithPostfixKey << " | "
      << IntegrateWithSendmailKey << " | "
      << IntegrateWithNoneKey << " "
      << UtilityConfig::HelpCommandLine() << "\n\n"
      << "SNFMilterConfig creates the configuration files (snf-config-file and the ignore list file) and the\n"
      << "rulebase download script (default: getRulebase) if they don't exist.\n\n"
      << "  -config=snf-config-file    Specifies the configuration file\n"
      << "  -mta=postfix               Integrate with postfix\n"
      << "  -mta=sendmail              Integrate with sendmail\n"
      << "  -mta=none                  Remove any integration with all supported MTAs\n"
      << UtilityConfig::HelpDescription() << "\n"
      << "If snf-config-file is not specified, then the following file is used:\n\n"
      << "  " << DefaultConfigFile << "\n\n";

};

bool
SNFMilterConfig::GetCommandLineInput(int argc, char* argv[]) {

    int i;
    int NumCommandsFound = 0;
    string OneInput;
    string ConfigFile;

    for (i = 1; i < argc; i++) {                                                // Check each input.

        OneInput = argv[i];

        if (0 == OneInput.find(ConfigFileKey)) {

            ConfigFile = OneInput.substr(ConfigFileKey.length());

        } else if (OneInput == IntegrateWithNoneKey) {

	    Command = IntegrateWithNoneCmd;
	    NumCommandsFound++;

        } else if (OneInput == IntegrateWithPostfixKey) {

            Command = IntegrateWithPostfixCmd;
	    NumCommandsFound++;

        } else if (0 == OneInput.find(IntegrateWithSendmailKey)) {

            Command = IntegrateWithSendmailCmd;
	    NumCommandsFound++;

        } else {

	    // Process command-line input by the base class.
	    if (!ProcessCommandLineItem(OneInput)) {

                return false;                                                   // Illegal input.

	    }

        }

    }


    if (0 == ConfigFile.length()) {                                             // Load default config file name.

	ConfigFile = DefaultConfigFile;

    }

    LoadConfigFile(ConfigFile);
    LoadInfo();                                                                 // Load the file paths.
    LoadSocketInfo();                                                           // Load the socket path.

    return (NumCommandsFound == 1);

}

void
SNFMilterConfig::LoadSocketInfo() {

    std::string MilterElement = GetPlatformContents();

    ConfigurationData PlatformConfig(MilterElement.c_str(), MilterElement.length());

    ConfigurationElement SocketReader("milter");

    SocketReader
      .Element("socket")
          .Attribute("path", SocketFileName)
      .End("socket")
      .End("milter");

    SocketReader.interpret(PlatformConfig);

}

void
SNFMilterConfig::CreateSocketDir() {

    std::string SocketDir;

    std::string::size_type LastDirSepIndex = SocketFileName.rfind("/");

    SocketDir = ( (std::string::npos == LastDirSepIndex) ? SocketFileName : SocketFileName.substr(0, LastDirSepIndex));

    if (Verbose()) {

	cout << "Create the milter socket directory " << SocketDir << "...";

    }

    if (!Explain()) {

	if (!FileExists(SocketDir)) {

	    MkDir(SocketDir);

	}

	SetMode(SocketDir, S_IRUSR | S_IWUSR | S_IXUSR | S_IRGRP | S_IWGRP | S_IXGRP);
	SetOwnerGroup(SocketDir);

    }

    OutputVerboseEnd();

}

void
SNFMilterConfig::UpdateConfigFiles() {

    std::string ConfigFileName = GetConfigFileName();

    if (!FileExists(ConfigFileName)) {

        Copy(DefaultSampleConfigFile, ConfigFileName);                                 // Use SNFMilter.xml.sample.

    }

    SetMode(ConfigFileName, S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH);                    // Set permissions.
    SetOwnerGroup(ConfigFileName);                                                     // Set to sniffer user.

    UpdateLogDir();
    UpdateIgnoreListFile();

}

void
SNFMilterConfig::DoIntegrationCommand() {

    switch (Command) {

    case IntegrateWithNoneCmd:
	UnintegrateWithAll();
	break;

    case IntegrateWithPostfixCmd:
	IntegrateWithPostfix();
	break;

    case IntegrateWithSendmailCmd:
	IntegrateWithSendmail();
	break;

    default:

	{
	    ostringstream Temp;

	    Temp << "Internal error in SNFMilterConfig::DoCommand:  Invalid value of command:  " << Command;

	    throw runtime_error(Temp.str());

	}

    }

}

void
SNFMilterConfig::UnintegrateWithAll() {

    UnintegrateWithPostfix();
    UnintegrateWithSendmail();

    // TODO: Restart MTA.

    // Do not remove the socket directory; users might have placed
    // files in it.  This happened with the /tmp directory; it was
    // supposed to be only for files that would be deleted on reboot.
    // However, admins stored files that they wished to be persistent
    // across reboots in /tmp.

}

void
SNFMilterConfig::IntegrateWithPostfix() {

    UnintegrateWithAll();                                                       // Remove any existing integration.

    if (Verbose()) {

	cout << "Add to postfix file " << PostfixMainCfPath << ":  '"
	     << SnfMilterMainCfIntegrationString << "'...";

    }

    if (!Explain()) {

	ofstream Output;                                                            // Append the configuration.

	Output.open(PostfixMainCfPath.c_str(), ios::app);
	if (!Output) {
	    string Temp;

	    Temp = "Error opening the postfix configuration file " + PostfixMainCfPath;
	    Temp += " for writing:  ";
	    Temp += strerror(errno);
	    throw runtime_error(Temp);
	}

	Output << SnfMilterMainCfIntegrationString << "\n";
	if (!Output) {
	    string Temp;

	    Temp = "Error appending to the postfix configuration file " + PostfixMainCfPath;
	    Temp += ":  ";
	    Temp += strerror(errno);
	    throw runtime_error(Temp);
	}

	Output.close();
	if (!Output) {
	    string Temp;

	    Temp = "Error closing the postfix configuration file " + PostfixMainCfPath;
	    Temp += " after appending:  ";
	    Temp += strerror(errno);
	    throw runtime_error(Temp);
	}

    }

    OutputVerboseEnd();

    CreateSocketDir();

    StartOrRestartMta("postfix");

}

void
SNFMilterConfig::UnintegrateWithPostfix() {

    ifstream Input;

    if (Verbose()) {

	cout << "Remove any integration in postfix file " << PostfixMainCfPath << "--\n";

    }

    Input.open(PostfixMainCfPath.c_str());                                      // Read the contents.
    if (!Input) {
	string Temp;

	Temp = "Error opening the postfix configuration file " + PostfixMainCfPath;
	Temp += " for reading:  ";
	Temp += strerror(errno);
	throw runtime_error(Temp);
    }

    string Content;
    string Line;

    while (getline(Input, Line)) {

	if (string::npos != Line.find(SnfMilterMainCfSearchString)) {          // Check for integration line.

	    if (Verbose()) {

		cout << "  Remove '" << Line << "'...\n";

	    }
	    continue;                                                           // Do not copy this line.

	}

	Content += Line + "\n";                                                 // Copy this line.

    }

    if (!Input.eof()) {                                                         // Should be at end-of-file.
	string Temp;

	Temp = "Error reading the postfix configuration file " + PostfixMainCfPath;
	Temp += ":  ";
	Temp += strerror(errno);
	throw runtime_error(Temp);
    }

    Input.close();
    if (Input.bad()) {
	string Temp;

	Temp = "Error closing the postfix configuration file " + PostfixMainCfPath;
	Temp += " after reading:  ";
	Temp += strerror(errno);
	throw runtime_error(Temp);
    }


    if (!Explain()) {

	ofstream Output;                                                            // Write the updated contents.

	Output.open(PostfixMainCfPath.c_str(), ios::trunc);
	if (!Output) {
	    string Temp;

	    Temp = "Error opening the postfix configuration file " + PostfixMainCfPath;
	    Temp += " for writing:  ";
	    Temp += strerror(errno);
	    throw runtime_error(Temp);
	}

	Output << Content;
	if (!Output) {
	    string Temp;

	    Temp = "Error writing the postfix configuration file " + PostfixMainCfPath;
	    Temp += ":  ";
	    Temp += strerror(errno);
	    throw runtime_error(Temp);
	}

	Output.close();
	if (!Output) {
	    string Temp;

	    Temp = "Error closing the postfix configuration file " + PostfixMainCfPath;
	    Temp += " after writing:  ";
	    Temp += strerror(errno);
	    throw runtime_error(Temp);
	}

    }

    OutputVerboseEnd();

}

void
SNFMilterConfig::IntegrateWithSendmail() {

    throw runtime_error("Integration with sendmail is not implemented");

}

void
SNFMilterConfig::UnintegrateWithSendmail() {

    std::cerr << "Unintegration with sendmail is not implemented" << "\n";

}