/* $Id$
 *
 * Lasso - A free implementation of the Liberty Alliance specifications.
 *
 * Copyright (C) 2004 Entr'ouvert
 * http://lasso.entrouvert.org
 * 
 * Authors: Nicolas Clapies <nclapies@entrouvert.com>
 *          Valery Febvre <vfebvre@easter-eggs.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 * 
 * This program 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 General Public License for more details.
 * 
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */

#include <string.h>

#include <xmlsec/base64.h>

#include <lasso/xml/errors.h>
#include <lasso/environs/server.h>

#include <lasso/lasso_config.h>

#define LASSO_SERVER_NODE                  "Server"
#define LASSO_SERVER_METADATA_NODE         "ServerMetadata"
#define LASSO_SERVER_PROVIDERS_NODE        "Providers"
#define LASSO_SERVER_PROVIDERID_NODE       "ProviderID"
#define LASSO_SERVER_PRIVATE_KEY_NODE      "PrivateKey"
#define LASSO_SERVER_SECRET_KEY_NODE       "SecretKey"
#define LASSO_SERVER_CERTIFICATE_NODE      "Certificate"
#define LASSO_SERVER_SIGNATURE_METHOD_NODE "SignatureMethod"

struct _LassoServerPrivate
{
  gboolean dispose_has_run;
};

static GObjectClass *parent_class = NULL;

/*****************************************************************************/
/* private methods                                                           */
/*****************************************************************************/

static gint
lasso_server_add_lasso_provider(LassoServer   *server,
				LassoProvider *provider)
{
  g_return_val_if_fail(LASSO_IS_SERVER(server), -1);
  g_return_val_if_fail(LASSO_IS_PROVIDER(provider), -2);

  g_ptr_array_add(server->providers, provider);

  return 0;
}

/*****************************************************************************/
/* public methods                                                            */
/*****************************************************************************/

/**
 * lasso_server_add_provider:
 * @server: a LassoServer
 * @metadata: the provider metadata file
 * @public_key: the provider public key file (may be a certificate) or NULL
 * @ca_cert_chain: the provider CA certificate chain file or NULL
 * 
 * Adds a provider in a server.
 * 
 * Return value: 0 on success or a negative value if an error occurs.
 **/
gint
lasso_server_add_provider(LassoServer *server,
			  gchar       *metadata,
			  gchar       *public_key,
			  gchar       *ca_cert_chain)
{
  LassoProvider *provider;

  g_return_val_if_fail(LASSO_IS_SERVER(server), LASSO_PARAM_ERROR_BAD_TYPE_OR_NULL_OBJ);
  g_return_val_if_fail(metadata != NULL, LASSO_PARAM_ERROR_INVALID_VALUE);

  provider = lasso_provider_new(metadata, public_key, ca_cert_chain);
  if (provider != NULL) {
    g_ptr_array_add(server->providers, provider);
  }
  else {
    message(G_LOG_LEVEL_CRITICAL, "Failed to add new provider.\n");
    return LASSO_SERVER_ERROR_ADD_PROVIDER_FAILED;
  }

  return 0;
}

LassoServer*
lasso_server_copy(LassoServer *server)
{
  LassoServer *copy;
  LassoProvider *p;
  guint i;

  g_return_val_if_fail(LASSO_IS_SERVER(server), NULL);

  copy = LASSO_SERVER(g_object_new(LASSO_TYPE_SERVER, NULL));

  /* herited provider attrs */
  LASSO_PROVIDER(copy)->metadata = lasso_node_copy(LASSO_PROVIDER(server)->metadata);
  LASSO_PROVIDER(copy)->public_key    = g_strdup(LASSO_PROVIDER(server)->public_key);
  LASSO_PROVIDER(copy)->ca_cert_chain = g_strdup(LASSO_PROVIDER(server)->ca_cert_chain);
  /* server attrs */
  copy->providers = g_ptr_array_new();
  for (i=0; i<server->providers->len; i++) {
    p = g_ptr_array_index(server->providers, i);
    g_ptr_array_add(copy->providers, lasso_provider_copy(p));
  }
  copy->providerID  = g_strdup(server->providerID);
  copy->private_key = g_strdup(server->private_key);
  copy->secret_key  = g_strdup(server->secret_key);
  copy->certificate = g_strdup(server->certificate);
  copy->signature_method = server->signature_method;

  return copy;
}

void
lasso_server_destroy(LassoServer *server)
{
  g_object_unref(G_OBJECT(server));
}

gchar *
lasso_server_dump(LassoServer *server)
{
  LassoProvider  *provider;
  LassoNode      *server_node, *providers_node, *provider_node, *metadata_copy, *metadata_node;
  LassoNodeClass *metadata_class, *server_class, *providers_class;
  xmlChar        *signature_method_str, *dump;
  gint            i;

  g_return_val_if_fail(LASSO_IS_SERVER(server), NULL);

  server_node = lasso_node_new();
  server_class = LASSO_NODE_GET_CLASS(server_node);
  server_class->set_name(server_node, LASSO_SERVER_NODE);
  server_class->set_ns(server_node, lassoLassoHRef, NULL);

  /* Add lasso version in the xml node */
  server_class->set_prop(LASSO_NODE(server_node), "version", PACKAGE_VERSION);

  /* signature method */
  signature_method_str = g_new(gchar, 6);
  g_snprintf(signature_method_str, 6, "%d", server->signature_method);
  server_class->set_prop(server_node, LASSO_SERVER_SIGNATURE_METHOD_NODE, signature_method_str);
  g_free(signature_method_str);

  /* providerID */
  if (server->providerID != NULL) {
    server_class->set_prop(server_node, LASSO_SERVER_PROVIDERID_NODE, server->providerID);
  }
  /* private key */
  if (server->private_key != NULL) {
    server_class->set_prop(server_node, LASSO_SERVER_PRIVATE_KEY_NODE, server->private_key);
  }
  /* secret key */
  if (server->secret_key != NULL) {
    server_class->set_prop(server_node, LASSO_SERVER_SECRET_KEY_NODE, server->secret_key);
  }
  /* certificate */
  if (server->certificate != NULL) {
    server_class->set_prop(server_node, LASSO_SERVER_CERTIFICATE_NODE, server->certificate);
  }
  /* metadata */
  provider = LASSO_PROVIDER(server);
  if (provider->metadata != NULL) {
    metadata_node = lasso_node_new();
    metadata_class = LASSO_NODE_GET_CLASS(metadata_node);
    metadata_class->set_name(metadata_node, LASSO_SERVER_METADATA_NODE);
    metadata_class->set_ns(metadata_node, lassoLassoHRef, NULL);

    metadata_copy = lasso_node_copy(provider->metadata);
    metadata_class->add_child(metadata_node, metadata_copy, FALSE);
    lasso_node_destroy(metadata_copy);
    server_class->add_child(server_node, metadata_node, FALSE);
  }

  /* providers */
  providers_node = lasso_node_new();
  providers_class = LASSO_NODE_GET_CLASS(providers_node);
  providers_class->set_name(providers_node, LASSO_SERVER_PROVIDERS_NODE);
  for (i = 0; i<server->providers->len; i++) {
    dump = lasso_provider_dump(g_ptr_array_index(server->providers, i));
    provider_node = lasso_node_new_from_dump(dump);
    xmlFree(dump);
    providers_class->add_child(providers_node, provider_node, TRUE);
    lasso_node_destroy(provider_node);
  }
  server_class->add_child(server_node, providers_node, FALSE);
  lasso_node_destroy(providers_node);

  dump = lasso_node_export(server_node);
  lasso_node_destroy(server_node);

  return dump;
}

gchar*
lasso_server_get_first_providerID(LassoServer *server)
{
  LassoProvider *provider;

  if (server->providers->len > 0) {
    provider = (LassoProvider *)g_ptr_array_index(server->providers, 0);
    return lasso_provider_get_providerID(provider);
  }
  else {
    return NULL;
  }
}

LassoProvider*
lasso_server_get_provider(LassoServer  *server,
			  gchar        *providerID,
			  GError      **err)
{
  LassoProvider *provider;
  GError *tmp_err = NULL;

  if (err != NULL && *err != NULL) {
    g_set_error(err, g_quark_from_string("Lasso"),
		LASSO_PARAM_ERROR_CHECK_FAILED,
		lasso_strerror(LASSO_PARAM_ERROR_CHECK_FAILED));
    g_return_val_if_fail (err == NULL || *err == NULL, NULL);
  }

  provider = lasso_server_get_provider_ref(server, providerID, &tmp_err);

  if (provider != NULL) {
    return lasso_provider_copy(provider);
  }
  else {
    g_propagate_error (err, tmp_err);
  }

  return NULL;
}

LassoProvider*
lasso_server_get_provider_ref(LassoServer  *server,
			      gchar        *providerID,
			      GError      **err)
{
  LassoProvider *provider;
  xmlChar *id;
  int index, len;
  
  if (err != NULL && *err != NULL) {
    g_set_error(err, g_quark_from_string("Lasso"),
		LASSO_PARAM_ERROR_CHECK_FAILED,
		lasso_strerror(LASSO_PARAM_ERROR_CHECK_FAILED));
    g_return_val_if_fail (err == NULL || *err == NULL, NULL);
  }
  if (LASSO_IS_SERVER(server) == FALSE) {
    g_set_error(err, g_quark_from_string("Lasso"),
		LASSO_PARAM_ERROR_BAD_TYPE_OR_NULL_OBJ,
		lasso_strerror(LASSO_PARAM_ERROR_BAD_TYPE_OR_NULL_OBJ));
    g_return_val_if_fail(LASSO_IS_SERVER(server), NULL);
  }
  if (providerID == NULL) {
    g_set_error(err, g_quark_from_string("Lasso"),
		LASSO_PARAM_ERROR_INVALID_VALUE,
		lasso_strerror(LASSO_PARAM_ERROR_INVALID_VALUE));
    g_return_val_if_fail(providerID != NULL, NULL);
  }

  len = server->providers->len;
  for (index = 0; index<len; index++) {
    provider = g_ptr_array_index(server->providers, index);

    id = lasso_provider_get_providerID(provider);
    if (id != NULL) {
      if (xmlStrEqual(providerID, id)) {
	xmlFree(id);
	return provider;
      }
      xmlFree(id);
    }
  }

  /* no provider was found */
  g_set_error(err, g_quark_from_string("Lasso"),
	      LASSO_SERVER_ERROR_PROVIDER_NOT_FOUND,
	      lasso_strerror(LASSO_SERVER_ERROR_PROVIDER_NOT_FOUND),
	      providerID);
  /* print error msg here so that caller just check err->code */
  message(G_LOG_LEVEL_CRITICAL, err[0]->message);

  return NULL;
}

gchar *
lasso_server_get_providerID_from_hash(LassoServer *server,
				      gchar       *b64_hash)
{
  LassoProvider *provider;
  xmlChar *providerID, *hash_providerID;
  xmlChar *b64_hash_providerID;
  int i;

  g_return_val_if_fail(LASSO_IS_SERVER(server), NULL);
  g_return_val_if_fail(b64_hash != NULL, NULL);

  for (i=0; i<server->providers->len; i++) {
    provider = g_ptr_array_index(server->providers, i);
    providerID = lasso_provider_get_providerID(provider);
    if (providerID != NULL) {
      hash_providerID = lasso_sha1(providerID);
      b64_hash_providerID = xmlSecBase64Encode(hash_providerID, 20, 0);
      xmlFree(hash_providerID);
      if (xmlStrEqual(b64_hash_providerID, b64_hash)) {
	xmlFree(b64_hash_providerID);
	return providerID;
      }
      else {
	xmlFree(b64_hash_providerID);
	xmlFree(providerID);
      }
    }
  }

  /* failed to get the providerID */
  message(G_LOG_LEVEL_CRITICAL,
	  "Failed to get a providerID corresponding to the hash.\n")

  return NULL;
}

lassoSignatureMethod
lasso_server_get_signature_method(LassoServer *server)
{
  return server->signature_method;
}

void
lasso_server_set_signature_method(LassoServer          *server,
				  lassoSignatureMethod  signature_method)
{
  server->signature_method = signature_method;
}

/*****************************************************************************/
/* overrided parent class methods                                            */
/*****************************************************************************/

static void
lasso_server_dispose(LassoServer *server)
{
  guint i;

  if (server->private->dispose_has_run == TRUE) {
    return;
  }
  server->private->dispose_has_run = TRUE;

  debug("Server object 0x%x disposed ...\n", server);

  /* free allocated memory for providers array */
  for (i=0; i<server->providers->len; i++) {
    lasso_provider_destroy(server->providers->pdata[i]);
  }
  g_ptr_array_free(server->providers, TRUE);

  parent_class->dispose(G_OBJECT(server));
}

static void
lasso_server_finalize(LassoServer *server)
{
  debug("Server object 0x%x finalized ...\n", server);

  g_free(server->providerID);
  g_free(server->private_key);
  g_free(server->secret_key);
  g_free(server->certificate);

  g_free(server->private);

  parent_class->finalize(G_OBJECT(server));
}

/*****************************************************************************/
/* instance and class init functions                                         */
/*****************************************************************************/

static void
lasso_server_instance_init(LassoServer *server)
{
  server->private = g_new (LassoServerPrivate, 1);
  server->private->dispose_has_run = FALSE;

  server->providers = g_ptr_array_new();
  server->providerID  = NULL;
  server->private_key = NULL;
  server->secret_key = NULL;
  server->certificate = NULL;
  server->signature_method = lassoSignatureMethodRsaSha1;
}

static void
lasso_server_class_init(LassoServerClass *class) {
  GObjectClass *gobject_class = G_OBJECT_CLASS(class);
  
  parent_class = g_type_class_peek_parent(class);
  /* override parent class methods */
  gobject_class->dispose  = (void *)lasso_server_dispose;
  gobject_class->finalize = (void *)lasso_server_finalize;
}

GType lasso_server_get_type() {
  static GType this_type = 0;

  if (!this_type) {
    static const GTypeInfo this_info = {
      sizeof (LassoServerClass),
      NULL,
      NULL,
      (GClassInitFunc) lasso_server_class_init,
      NULL,
      NULL,
      sizeof(LassoServer),
      0,
      (GInstanceInitFunc) lasso_server_instance_init,
    };
    
    this_type = g_type_register_static(LASSO_TYPE_PROVIDER,
				       "LassoServer",
				       &this_info, 0);
  }
  return this_type;
}

/**
 * lasso_server_new:
 * @metadata: the server metadata file
 * @private_key: the server private key or NULL
 * @secret_key: the server secret key (to decrypt the private key)
 * @certificate: the server certificate
 * 
 * Creates a server. The caller is responsible for destroying returned
 * object by calling #lasso_server_destroy method.
 * 
 * Return value: a newly allocated #LassoServer object or NULL if an error occurs.
 **/
LassoServer *
lasso_server_new(const gchar *metadata,
		 const gchar *private_key,
		 const gchar *secret_key,
		 const gchar *certificate)
{
  LassoServer *server;
  xmlDocPtr    doc;
  xmlNodePtr   root;
  LassoNode   *md_node = NULL;
  gchar       *providerID = NULL;
  GError      *err = NULL;

  /* metadata can be NULL (if server is a LECP) */

  /* put server metadata in a LassoNode */
  if (metadata != NULL) {
    doc = xmlParseFile(metadata);
    if (doc == NULL) {
      message(G_LOG_LEVEL_CRITICAL, "Failed to parse file \"%s\"\n", metadata);
      return NULL;
    }
    root = xmlCopyNode(xmlDocGetRootElement(doc), 1);
    xmlFreeDoc(doc);
    md_node = lasso_node_new();
    LASSO_NODE_GET_CLASS(md_node)->set_xmlNode(md_node, root);
 
    /* get ProviderID in metadata */
    providerID = lasso_node_get_attr_value(md_node, "providerID", &err);
    if (providerID == NULL) {
      message(G_LOG_LEVEL_WARNING, err->message);
      g_error_free(err);
      lasso_node_destroy(md_node);
      return NULL;
    }
  }

  /* Ok, we can create server */
  server = LASSO_SERVER(g_object_new(LASSO_TYPE_SERVER, NULL));

  if (md_node != NULL) {
    LASSO_PROVIDER(server)->metadata = md_node;
  }
  if (providerID != NULL) {
    server->providerID = providerID;
  }
  server->private_key = g_strdup(private_key);
  server->secret_key  = g_strdup(secret_key);
  server->certificate = g_strdup(certificate);

  return server;
}

LassoServer *
lasso_server_new_from_dump(gchar *dump)
{
  LassoNodeClass *server_class, *providers_class;
  LassoNode      *server_node, *providers_node, *provider_node, *entity_node, *server_metadata_node;
  LassoServer    *server;
  LassoProvider  *provider;
  xmlNodePtr      providers_xmlNode, provider_xmlNode;
  xmlChar        *public_key, *ca_cert_chain, *signature_method;

  server = LASSO_SERVER(g_object_new(LASSO_TYPE_SERVER, NULL));

  server_node  = lasso_node_new_from_dump(dump);
  if (server_node == NULL) {
    message(G_LOG_LEVEL_WARNING, "Error while loading server dump\n");
    return NULL;
  }
  server_class = LASSO_NODE_GET_CLASS(server_node);
  if (strcmp(server_class->get_name(server_node), LASSO_SERVER_NODE) != 0) {
    message(G_LOG_LEVEL_WARNING, "XML is not a server dump\n");
    lasso_node_destroy(server_node);
    return NULL;
  }

  /* providerID */
  server->providerID = lasso_node_get_attr_value(server_node, LASSO_SERVER_PROVIDERID_NODE, NULL);

  /* private key */
  server->private_key = lasso_node_get_attr_value(server_node, LASSO_SERVER_PRIVATE_KEY_NODE, NULL);

  /* secret key */
  server->secret_key = lasso_node_get_attr_value(server_node, LASSO_SERVER_SECRET_KEY_NODE, NULL);

  /* certificate */
  server->certificate = lasso_node_get_attr_value(server_node, LASSO_SERVER_CERTIFICATE_NODE, NULL);

  /* signature method */
  signature_method = lasso_node_get_attr_value(server_node, LASSO_SERVER_SIGNATURE_METHOD_NODE, NULL);
  if (signature_method != NULL) {
    server->signature_method = atoi(signature_method);
    xmlFree(signature_method);
  }

  /* metadata */
  server_metadata_node = lasso_node_get_child(server_node, LASSO_SERVER_METADATA_NODE, NULL, NULL);
  if (server_metadata_node != NULL) {
    entity_node = lasso_node_get_child(server_metadata_node, "EntityDescriptor", NULL, NULL);
    LASSO_PROVIDER(server)->metadata = lasso_node_copy(entity_node);
    lasso_node_destroy(entity_node);
  }

  /* public key */
  LASSO_PROVIDER(server)->public_key = lasso_node_get_attr_value(server_node, LASSO_PROVIDER_PUBLIC_KEY_NODE, NULL);

  /* ca_cert_chain */
  LASSO_PROVIDER(server)->ca_cert_chain = lasso_node_get_attr_value(server_node, LASSO_PROVIDER_CA_CERT_CHAIN_NODE, NULL);

  /* providers */
  providers_node  = lasso_node_get_child(server_node, LASSO_SERVER_PROVIDERS_NODE, lassoLassoHRef, NULL);
  if (providers_node != NULL) {
    providers_class = LASSO_NODE_GET_CLASS(providers_node);
    providers_xmlNode = providers_class->get_xmlNode(providers_node);
    provider_xmlNode = providers_xmlNode->children;

    while (provider_xmlNode != NULL) {
      if (provider_xmlNode->type == XML_ELEMENT_NODE && \
	  xmlStrEqual(provider_xmlNode->name, LASSO_PROVIDER_NODE)) {
	/* provider node */
	provider_node = lasso_node_new_from_xmlNode(provider_xmlNode);

	/*  metadata */
	entity_node = lasso_node_get_child(provider_node, "EntityDescriptor", NULL, NULL);

	/* public key */
	public_key = lasso_node_get_attr_value(provider_node, LASSO_PROVIDER_PUBLIC_KEY_NODE, NULL);

	/* ca certificate */
	ca_cert_chain = lasso_node_get_attr_value(provider_node, LASSO_PROVIDER_CA_CERT_CHAIN_NODE, NULL);

	/* add provider */
	provider = lasso_provider_new_from_metadata_node(entity_node);
	lasso_node_destroy(entity_node);
	if (public_key != NULL) {
	  lasso_provider_set_public_key(provider, public_key);
	  xmlFree(public_key);
	}
	if (ca_cert_chain != NULL) {
	  lasso_provider_set_ca_cert_chain(provider, ca_cert_chain);
	  xmlFree(ca_cert_chain);
	}
	lasso_server_add_lasso_provider(server, provider);

	lasso_node_destroy(provider_node);
      }

      provider_xmlNode = provider_xmlNode->next;
    }

    lasso_node_destroy(providers_node);
  }

  lasso_node_destroy(server_node);

  return server;
}