// -*- mode: c++; c-basic-offset:4 -*-

// This file is part of libdap, A C++ implementation of the OPeNDAP Data

// Access Protocol.

// Copyright (c) 2002,2003 OPeNDAP, Inc.

// Author: Jose Garcia <jgarcia@ucar.edu>

//

// This library is free software; you can redistribute it and/or

// modify it under the terms of the GNU Lesser General Public

// License as published by the Free Software Foundation; either

// version 2.1 of the License, or (at your option) any later version.

//

// This library is distributed in the hope that it will be useful,

// but WITHOUT ANY WARRANTY; without even the implied warranty of

// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU

// Lesser General Public License for more details.

//

// You should have received a copy of the GNU Lesser General Public

// License along with this library; if not, write to the Free Software

// Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA

//

// You can contact OPeNDAP, Inc. at PO Box 112, Saunderstown, RI. 02874-0112.

// (c) COPYRIGHT URI/MIT 2001,2002

// Please read the full copyright statement in the file COPYRIGHT_URI.

//

// Authors:

// jose Jose Garcia <jgarcia@ucar.edu>

/** A singleton which reads and parses the .dodsrc file. This code was

 extracted from Connect (which has since changed considerably).

 @author: jose */

// #define DODS_DEBUG

#include "config.h"

#include <cstring>

#include <cstdlib>

#include <unistd.h>  // for stat

#include <sys/types.h>

#include <sys/stat.h>

#ifdef WIN32

#define FALSE 0

// Win32 does not define F_OK. 08/21/02 jhrg

#define F_OK 0

#define DIR_SEP_STRING "\\"

#define DIR_SEP_CHAR   '\\'

#include <direct.h>

#else

#define DIR_SEP_STRING "/"

#define DIR_SEP_CHAR   '/'

#endif

#include <pthread.h>

#include <fstream>

#include "debug.h"

#include "RCReader.h"

#include "Error.h"

using namespace std;

namespace libdap {

RCReader* RCReader::_instance = 0;

// This variable (instance_control) is used to ensure that in a MT

// environment _instance is correctly initialized. See the get_instance

// method. 08/07/02 jhrg

static pthread_once_t instance_control = PTHREAD_ONCE_INIT;

/** Using values from this instance of RCReader, write out values for a

 default .dodsrc file. Nominally this will use the defaults for each thing

 that might be read from the configuration file. */

bool RCReader::write_rc_file(const string &pathname)

{

    DBG(cerr << "Writing the RC file to " << pathname << endl);

    ofstream fpo(pathname.c_str());

    // If the file couldn't be created.  Nothing needs to be done here,

    // the program will simply use the defaults.

    if (fpo) {

        // This means we just created the file.  We will now save

        // the defaults in it for future use.

        fpo << "# OPeNDAP client configuration file. See the OPeNDAP" << endl;

        fpo << "# users guide for information." << endl;

        fpo << "USE_CACHE=" << _dods_use_cache << endl;

        fpo << "# Cache and object size are given in megabytes (20 ==> 20Mb)." << endl;

        fpo << "MAX_CACHE_SIZE=" << _dods_cache_max << endl;

        fpo << "MAX_CACHED_OBJ=" << _dods_cached_obj << endl;

        fpo << "IGNORE_EXPIRES=" << _dods_ign_expires << endl;

        fpo << "CACHE_ROOT=" << d_cache_root << endl;

        fpo << "DEFAULT_EXPIRES=" << _dods_default_expires << endl;

        fpo << "ALWAYS_VALIDATE=" << _dods_always_validate << endl;

        fpo << "# Request servers compress responses if possible?" << endl;

        fpo << "# 1 (yes) or 0 (false)." << endl;

        fpo << "DEFLATE=" << _dods_deflate << endl;

        fpo << "# Should SSL certificates and hosts be validated? SSL" << endl;

        fpo << "# will only work with signed certificates." << endl;

        fpo << "VALIDATE_SSL=" << d_validate_ssl << endl;

        fpo << "# Proxy configuration (optional parts in []s)." << endl;

        fpo << "# You may also use the 'http_proxy' environment variable" << endl;

        fpo << "# but a value in this file will override that env variable." << endl;

        fpo << "# PROXY_SERVER=[http://][username:password@]host[:port]" << endl;

        if (!d_dods_proxy_server_host.empty()) {

            fpo << "PROXY_SERVER=" << d_dods_proxy_server_protocol << "://"

                    << (d_dods_proxy_server_userpw.empty() ? "" : d_dods_proxy_server_userpw + "@")

                            + d_dods_proxy_server_host + ":" + long_to_string(d_dods_proxy_server_port) << endl;

        }

        fpo << "# NO_PROXY_FOR=<host|domain>" << endl;

        if (!d_dods_no_proxy_for_host.empty()) {

            fpo << "NO_PROXY_FOR=" << d_dods_no_proxy_for_host << endl;

        }

        fpo << "# AIS_DATABASE=<file or url>" << endl;

        fpo << "# COOKIE_JAR=.dods_cookies" << endl;

        fpo << "# The cookie jar is a file that holds cookies sent from" << endl;

        fpo << "# servers such as single signon systems. Uncomment this" << endl;

        fpo << "# option and provide a file name to activate this feature." << endl;

        fpo << "# If the value is a filename, it will be created in this" << endl;

        fpo << "# directory; a full pathname can be used to force a specific" << endl;

        fpo << "# location." << endl;

        fpo.close();

        return true;

    }

    return false;

}

bool RCReader::read_rc_file(const string &pathname)

{

    DBG(cerr << "Reading the RC file from " << pathname << endl);

    ifstream fpi(pathname.c_str());

    if (fpi) {

        // The file exists and we may now begin to parse it.

        // Defaults are already stored in the variables, if the correct

        // tokens are found in the file then those defaults will be

        // overwritten.

        char *value;

        // TODO Replace with a vector<char>

        //char *tempstr = new char[1024];

        vector<char> tempstr(1024);

        int tokenlength;

        while (true) {

            fpi.getline(&tempstr[0], 1023);

            if (!fpi.good()) break;

            value = strchr(&tempstr[0], '=');

            if (!value) continue;

            tokenlength = value - &tempstr[0];

            value++;

            if ((strncmp(&tempstr[0], "USE_CACHE", 9) == 0) && tokenlength == 9) {

                _dods_use_cache = atoi(value) ? true : false;

            }

            else if ((strncmp(&tempstr[0], "MAX_CACHE_SIZE", 14) == 0) && tokenlength == 14) {

                _dods_cache_max = atoi(value);

            }

            else if ((strncmp(&tempstr[0], "MAX_CACHED_OBJ", 14) == 0) && tokenlength == 14) {

                _dods_cached_obj = atoi(value);

            }

            else if ((strncmp(&tempstr[0], "IGNORE_EXPIRES", 14) == 0) && tokenlength == 14) {

                _dods_ign_expires = atoi(value);

            }

            else if ((strncmp(&tempstr[0], "DEFLATE", 7) == 0) && tokenlength == 7) {

                _dods_deflate = atoi(value) ? true : false;

            }

            else if ((strncmp(&tempstr[0], "CACHE_ROOT", 10) == 0) && tokenlength == 10) {

                d_cache_root = value;

                if (d_cache_root[d_cache_root.length() - 1] != DIR_SEP_CHAR) d_cache_root += string(DIR_SEP_STRING);

            }

            else if ((strncmp(&tempstr[0], "DEFAULT_EXPIRES", 15) == 0) && tokenlength == 15) {

                _dods_default_expires = atoi(value);

            }

            else if ((strncmp(&tempstr[0], "ALWAYS_VALIDATE", 15) == 0) && tokenlength == 15) {

                _dods_always_validate = atoi(value);

            }

            else if ((strncmp(&tempstr[0], "VALIDATE_SSL", 12) == 0) && tokenlength == 12) {

                d_validate_ssl = atoi(value);

            }

            else if (strncmp(&tempstr[0], "AIS_DATABASE", 12) == 0 && tokenlength == 12) {

                d_ais_database = value;

            }

            else if (strncmp(&tempstr[0], "COOKIE_JAR", 10) == 0 && tokenlength == 10) {

                // if the value of COOKIE_JAR starts with a slash, use it as

                // is. However, if it does not start with a slash, prefix it

                // with the directory that contains the .dodsrc file.

                if (value[0] == '/') {

                    d_cookie_jar = value;

                }

                else {

                    d_cookie_jar = d_rc_file_path.substr(0, d_rc_file_path.find(".dodsrc")) + string(value);

                } DBG(cerr << "set cookie jar to: " << d_cookie_jar << endl);

            }

            else if ((strncmp(&tempstr[0], "PROXY_SERVER", 12) == 0) && tokenlength == 12) {

                // Setup a proxy server for all requests.

                // The original syntax was <protocol>,<machine> where the

                // machine could also contain the user/pass and port info.

                // Support that but also support machine prefixed by

                // 'http://' with and without the '<protocol>,' prefix. jhrg

                // 4/21/08 (see bug 1095).

                string proxy = value;

                string::size_type comma = proxy.find(',');

                // Since the <protocol> is now optional, the comma might be

                // here. If it is, check that the protocol given is http.

                if (comma != string::npos) {

                    d_dods_proxy_server_protocol = proxy.substr(0, comma);

                    downcase(d_dods_proxy_server_protocol);

                    if (d_dods_proxy_server_protocol != "http")

                        throw Error("The only supported protocol for a proxy server is \"HTTP\". Correct your \".dodsrc\" file.");

                    proxy = proxy.substr(comma + 1);

                }

                else {

                    d_dods_proxy_server_protocol = "http";

                }

                // Look for a 'protocol://' prefix; skip if found

                string::size_type protocol = proxy.find("://");

                if (protocol != string::npos) {

                    proxy = proxy.substr(protocol + 3);

                }

                // Break apart into userpw, host and port.

                string::size_type at_sign = proxy.find('@');

                if (at_sign != string::npos) { // has userpw

                    d_dods_proxy_server_userpw = proxy.substr(0, at_sign);

                    proxy = proxy.substr(at_sign + 1);

                }

                else

                    d_dods_proxy_server_userpw = "";

                // Get host and look for a port number

                string::size_type colon = proxy.find(':');

                if (colon != string::npos) {

                    d_dods_proxy_server_host = proxy.substr(0, colon);

                    d_dods_proxy_server_port = strtol(proxy.substr(colon + 1).c_str(), 0, 0);

                }

                else {

                    d_dods_proxy_server_host = proxy;

                    d_dods_proxy_server_port = 80;

                }

            }

            else if ((strncmp(&tempstr[0], "NO_PROXY_FOR", 12) == 0) && tokenlength == 12) {

                // Setup a proxy server for all requests.

                string no_proxy = value;

                string::size_type comma = no_proxy.find(',');

                // Since the protocol is required, the comma *must* be

                // present. We could throw an Error on the malformed line...

                if (comma == string::npos) {

                    d_dods_no_proxy_for_protocol = "http";

                    d_dods_no_proxy_for_host = no_proxy;

                    d_dods_no_proxy_for = true;

                }

                else {

                    d_dods_no_proxy_for_protocol = no_proxy.substr(0, comma);

                    d_dods_no_proxy_for_host = no_proxy.substr(comma + 1);

                    d_dods_no_proxy_for = true;

                }

            }

        }

        //delete [] tempstr; tempstr = 0;

        fpi.close(); // Close the .dodsrc file. 12/14/99 jhrg

        return true;

    }  // End of cache file parsing.

    return false;

}

// Helper for check_env_var(). This is its main logic, separated out for the

// cases under WIN32 where we don't use an environment variable.  09/19/03

// jhrg

string RCReader::check_string(string env_var)

{

    DBG(cerr << "Entering check_string... (" << env_var << ")" << endl);

    struct stat stat_info;

    if (stat(env_var.c_str(), &stat_info) != 0) {

        DBG(cerr << "stat returned non-zero" << endl);

        return "";  // ENV VAR not a file or dir, bail

    }

    if (S_ISREG(stat_info.st_mode)) {

        DBG(cerr << "S_ISREG: " << S_ISREG(stat_info.st_mode) << endl);

        return env_var;  // ENV VAR is a file, use it

    }

    // ENV VAR is a directory, does it contain .dodsrc? Can we create

    // .dodsrc if it's not there?

    if (S_ISDIR(stat_info.st_mode)) {

        DBG(cerr << "S_ISDIR: " << S_ISDIR(stat_info.st_mode) << endl);

        if (*env_var.rbegin() != DIR_SEP_CHAR) // Add trailing / if missing

            env_var += DIR_SEP_STRING;

        // Trick: set d_cache_root here in case we're going to create the

        // .dodsrc later on. If the .dodsrc file exists, its value will

        // overwrite this value, if not write_rc_file() will use the correct

        // value. 09/19/03 jhrg

        d_cache_root = env_var + string(".dods_cache") + DIR_SEP_STRING;

        env_var += ".dodsrc";

        if (stat(env_var.c_str(), &stat_info) == 0 && S_ISREG(stat_info.st_mode)) {

            DBG(cerr << "Found .dodsrc in \"" << env_var << "\"" << endl);

            return env_var; // Found .dodsrc in ENV VAR

        }

        // Didn't find .dodsrc in ENV VAR and ENV VAR is a directory; try to

        // create it. Note write_rc_file uses d_cache_root (set above) when

        // it creates the RC file's contents.

        if (write_rc_file(env_var)) {

            DBG(cerr << "Wrote .dodsrc in \"" << env_var << "\"" << endl);

            return env_var;

        }

    }

    // If we're here, then we've neither found nor created the RC file.

    DBG(cerr << "could neither find nor create a .dodsrc file" << endl);

    return "";

}

/** Examine an environment variable. If the env variable is set, then if

 this is the name of a file, use that as the name of the RC file. If this

 is the name of a directory, look in that directory for a file called

 .dodsrc. If there's no such file, create it using default values for its

 parameters. In the last case, write the .dodsrc so that the .dods_cache

 directory is located in the directory named by DODS_CONF.

 @return The pathname to the RC file or "" if another variable/method

 should be used to find/create the RC file. */

string RCReader::check_env_var(const string &variable_name)

{

    char *ev = getenv(variable_name.c_str());

    if (!ev || strlen(ev) == 0) return "";

    return check_string(ev);

}

RCReader::RCReader() // throw (Error) jhrg 7/2/15

{

    d_rc_file_path = "";

    d_cache_root = "";

    // ** Set default values **

    // Users must explicitly turn caching on.

    _dods_use_cache = false;

    _dods_cache_max = 20;

    _dods_cached_obj = 5;

    _dods_ign_expires = 0;

    _dods_default_expires = 86400;

    _dods_always_validate = 0;

    _dods_deflate = 0;

    d_validate_ssl = 1;

    //flags for PROXY_SERVER=<protocol>,<host url>

    // New syntax PROXY_SERVER=[http://][user:pw@]host[:port]

    d_dods_proxy_server_protocol = "";

    d_dods_proxy_server_host = "";

    d_dods_proxy_server_port = 0;

    d_dods_proxy_server_userpw = "";

    _dods_proxy_server_host_url = ""; // deprecated

    // PROXY_FOR is deprecated.

    // flags for PROXY_FOR=<regex>,<proxy host url>,<flags>

    _dods_proxy_for = false; // true if proxy_for is used.

    _dods_proxy_for_regexp = "";

    _dods_proxy_for_proxy_host_url = "";

    _dods_proxy_for_regexp_flags = 0;

    //flags for NO_PROXY_FOR=<protocol>,<host>,<port>

    // New syntax NO_PROXY_FOR=<host|domain>

    d_dods_no_proxy_for = false;

    d_dods_no_proxy_for_protocol = ""; // deprecated

    d_dods_no_proxy_for_host = "";

    // default to port 0 if not specified. This means all ports. Using 80

    // will fail when the URL does not contain the port number. That's

    // probably a bug in libwww. 10/23/2000 jhrg

    _dods_no_proxy_for_port = 0; // deprecated

    d_cookie_jar = "";

#ifdef WIN32

    string homedir = string("C:") + string(DIR_SEP_STRING) + string("Dods");

    d_rc_file_path = check_string(homedir);

    if (d_rc_file_path.empty()) {

        homedir = string("C:") + string(DIR_SEP_STRING) + string("opendap");

        d_rc_file_path = check_string(homedir);

    }

    //  Normally, I'd prefer this for WinNT-based systems.

    if (d_rc_file_path.empty())

    d_rc_file_path = check_env_var("APPDATA");

    if (d_rc_file_path.empty())

    d_rc_file_path = check_env_var("TEMP");

    if (d_rc_file_path.empty())

    d_rc_file_path = check_env_var("TMP");

#else

    d_rc_file_path = check_env_var("DODS_CONF");

    if (d_rc_file_path.empty()) d_rc_file_path = check_env_var("HOME");

#endif

    DBG(cerr << "Looking for .dodsrc in: " << d_rc_file_path << endl);

    if (!d_rc_file_path.empty()) read_rc_file(d_rc_file_path);

}

RCReader::~RCReader()

{

}

/** Static void private method. */

void RCReader::delete_instance()

{

    if (RCReader::_instance) {

        delete RCReader::_instance;

        RCReader::_instance = 0;

    }

}

/** Static void private method. */

void RCReader::initialize_instance()

{

    DBGN(cerr << "RCReader::initialize_instance() ... ");

    RCReader::_instance = new RCReader;

    atexit(RCReader::delete_instance);

    DBG(cerr << "exiting." << endl);

}

RCReader*

RCReader::instance()

{

    DBG(cerr << "Entring RCReader::instance" << endl);

    // The instance_control variable is defined at the top of this file.

    // 08/07/02 jhrg

    pthread_once(&instance_control, initialize_instance);

    DBG(cerr << "Instance value: " << hex << _instance << dec << endl);

    return _instance;

}

#if 0

RCReader*

RCReader::instance(const string &rc_file_path)

{

    DBG(cerr << "Entring RCReader::instance" << endl);

    d_rc_file_path = rc_file_path;

    // The instance_control variable is defined at the top of this file.

    // 08/07/02 jhrg

    pthread_once(&instance_control, initialize_instance);

    DBG(cerr << "Instance value: " << hex << _instance << dec << endl);

    return _instance;

}

#endif

} // namespace libdap