/*
 *  Copyright (C) 2001 Matt Aubury, Philip Langdale
 *  Copyright (C) 2004 Crispin Flowerday
 *  Copyright (C) 2005 Christian Persch
 *  Copyright (C) 2005 Adam Hooper
 *
 *  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, 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.
 *
 *  $Id$
 */

#include "mozilla-config.h"

#include "config.h"

#include <nsCOMPtr.h>
#include <nsIIOService.h>
#include <nsIServiceManager.h>
#include <nsIURI.h>
#include <nsIChannel.h>
#include <nsIOutputStream.h>
#include <nsIInputStream.h>
#include <nsIStorageStream.h>
#include <nsIInputStreamChannel.h>
#include <nsIScriptSecurityManager.h>
#include <nsNetCID.h>
#include <nsString.h>
#include <nsEscape.h>

#include <glib/gi18n.h>
#include <gtk/gtk.h>

#include "EphyProtocolHandler.h"
#include "EphyUtils.h"

#include "ephy-debug.h"

#include <string.h>

static NS_DEFINE_CID(kSimpleURICID, NS_SIMPLEURI_CID);
static NS_DEFINE_CID(kInputStreamChannelCID, NS_INPUTSTREAMCHANNEL_CID);

EphyProtocolHandler::EphyProtocolHandler()
{
	LOG ("EphyProtocolHandler ctor [%p]\n", this);
}

EphyProtocolHandler::~EphyProtocolHandler()
{
	LOG ("EphyProtocolHandler dtor [%p]\n", this);
}

NS_IMPL_ISUPPORTS2 (EphyProtocolHandler, nsIProtocolHandler, nsIAboutModule)

/* readonly attribute string scheme; */
NS_IMETHODIMP
EphyProtocolHandler::GetScheme(nsACString &aScheme)
{
	aScheme.Assign("epiphany");
	return NS_OK;
}

/* readonly attribute long defaultPort; */
NS_IMETHODIMP
EphyProtocolHandler::GetDefaultPort(PRInt32 *aDefaultPort)
{
	NS_ENSURE_ARG_POINTER (aDefaultPort);

	*aDefaultPort = -1;
	return NS_OK;
}

/* readonly attribute short protocolFlags; */
NS_IMETHODIMP
EphyProtocolHandler::GetProtocolFlags(PRUint32 *aProtocolFlags)
{
	NS_ENSURE_ARG_POINTER (aProtocolFlags);

	*aProtocolFlags = nsIProtocolHandler::URI_NORELATIVE | nsIProtocolHandler::URI_NOAUTH;
	return NS_OK;
} 

/* nsIURI newURI (in string aSpec, in nsIURI aBaseURI); */
NS_IMETHODIMP
EphyProtocolHandler::NewURI(const nsACString &aSpec,
			    const char *aOriginCharset,
			    nsIURI *aBaseURI,
			    nsIURI **_retval)
{
	nsresult rv;
	nsCOMPtr<nsIURI> uri (do_CreateInstance(kSimpleURICID, &rv));
	NS_ENSURE_SUCCESS (rv, rv);

	rv = uri->SetSpec (aSpec);
	NS_ENSURE_SUCCESS (rv, rv);

	NS_ADDREF(*_retval = uri);
	return NS_OK;
}

/* nsIChannel newChannel (in nsIURI aURI); */
NS_IMETHODIMP
EphyProtocolHandler::NewChannel(nsIURI *aURI,
				nsIChannel **_retval)
{
	NS_ENSURE_ARG(aURI);

	PRBool isEpiphany = PR_FALSE;
	if (NS_SUCCEEDED (aURI->SchemeIs ("epiphany", &isEpiphany)) && isEpiphany)
	{
		return HandleEpiphany (aURI, _retval);
	}

	PRBool isAbout = PR_FALSE;
	if (NS_SUCCEEDED (aURI->SchemeIs ("about", &isAbout)) && isAbout)
	{
		return Redirect (nsDependentCString ("file://" SHARE_DIR "/epiphany.xhtml"), _retval);
	}

	return NS_ERROR_ILLEGAL_VALUE;
}

/* boolean allowPort (in long port, in string scheme); */
NS_IMETHODIMP 
EphyProtocolHandler::AllowPort(PRInt32 port,
			       const char *scheme,
			       PRBool *_retval)
{
	*_retval = PR_FALSE;
	return NS_OK;
}

/* private functions */

nsresult
EphyProtocolHandler::Redirect(const nsACString &aURL,
			      nsIChannel **_retval)
{
	nsresult rv;
	nsCOMPtr<nsIIOService> ioService;
	rv = EphyUtils::GetIOService (getter_AddRefs (ioService));
	NS_ENSURE_SUCCESS (rv, rv);

	nsCOMPtr<nsIChannel> tempChannel;
	rv = ioService->NewChannel(aURL, nsnull, nsnull, getter_AddRefs(tempChannel));
	NS_ENSURE_SUCCESS (rv, rv);

	nsCOMPtr<nsIURI> uri;
	rv = ioService->NewURI(aURL, nsnull, nsnull, getter_AddRefs(uri));
	NS_ENSURE_SUCCESS (rv, rv);

	tempChannel->SetOriginalURI (uri);

	nsCOMPtr<nsIScriptSecurityManager> securityManager = 
			do_GetService(NS_SCRIPTSECURITYMANAGER_CONTRACTID, &rv);
	NS_ENSURE_SUCCESS (rv, rv);

	nsCOMPtr<nsIPrincipal> principal;
	rv = securityManager->GetCodebasePrincipal(uri, getter_AddRefs(principal));
	NS_ENSURE_SUCCESS (rv, rv);

	rv = tempChannel->SetOwner(principal);
	NS_ENSURE_SUCCESS (rv, rv);

	NS_ADDREF(*_retval = tempChannel);
	return rv;
}

nsresult
EphyProtocolHandler::ParseErrorURL(const char *aURL,
				   nsACString &aError,
				   nsACString &aOriginURL,
				   nsACString &aOriginCharset)
{
	/* The error page URL is of the form "epiphany:error?e=<error>&u=<URL>&c=<charset>&d=<description>" */
	const char *query = strstr (aURL, "?");
	if (!query) return NS_ERROR_FAILURE;
	
	/* skip the '?' */
	++query;
	
	char **params = g_strsplit (query, "&", -1);
	if (!params) return NS_ERROR_FAILURE;
	
	for (PRUint32 i = 0; params[i] != NULL; ++i)
	{
		char *param = params[i];
	
		if (strlen (param) <= 2) continue;
	
		switch (param[0])
		{
			case 'e':
				aError.Assign (nsUnescape (param + 2));
				break;
			case 'u':
				aOriginURL.Assign (nsUnescape (param + 2));
				break;
			case 'c':
				aOriginCharset.Assign (nsUnescape (param + 2));
				break;
			case 'd':
				/* we don't need mozilla's description parameter */
			default:
				break;
		}
	}

	g_strfreev (params);
	
	return NS_OK;
}

nsresult
EphyProtocolHandler::GetErrorMessage(nsIURI *aURI,
				     const char *aError,
				     char **aPrimary,
				     char **aSecondary)
{
	if (strcmp (aError, "protocolNotFound") == 0)
	{
		nsCAutoString scheme;
		aURI->GetScheme (scheme);

		*aPrimary = g_strdup (_("Unknown protocol"));
		/* FIXME: get the list of supported protocols from necko */
		*aSecondary = g_strdup_printf (_("The \"%s\" protocol could not be recognised. "
						 "Epiphany supports \"http\", \"https\", \"ftp\", "
						 "\"smb\" and \"sftp\"  protocols."),
					       scheme.get());
	}
	else if (strcmp (aError, "fileNotFound") == 0)
	{
		nsCAutoString path;
		aURI->GetPath (path);

		*aPrimary = g_strdup (_("File not found"));
		*aSecondary = g_strdup_printf (_("The file \"%s\" could not be found. "
						 "Check the location of the file and try again."),
					       path.get());
	}
	else if (strcmp (aError, "dnsNotFound") == 0)
	{
		nsCAutoString host;
		aURI->GetHost (host);

		*aPrimary = g_strdup (_("Address not found"));
		*aSecondary = g_strdup_printf (_("\"%s\" could not be found. "
						 "Check the address and try again."),
					       host.get());
	}
	else if (strcmp (aError, "connectionFailure") == 0)
	{
		nsCAutoString hostport;
		aURI->GetHostPort (hostport);

		*aPrimary = g_strdup_printf (_("Could not connect to \"%s\""), hostport.get());
		*aSecondary = g_strdup (_("The server refused the connection. "
					  "Check the address and port and try again."));
	}
	else if (strcmp (aError, "netInterrupt") == 0)
	{
		nsCAutoString hostport;
		aURI->GetHostPort (hostport);

		*aPrimary = g_strdup (_("Connection interrupted"));
		*aSecondary = g_strdup_printf (_(" The connection to \"%s\" was interrupted. "
						 "The server may be very busy or you may have a "
						 "network connection problem."),
					       hostport.get());
	}
	else if (strcmp (aError, "netTimeout") == 0)
	{
		nsCAutoString host;
		aURI->GetHost (host);

		*aPrimary = g_strdup (_("Connection timed out"));
		*aSecondary = g_strdup_printf (_("The connection to \"%s\" was lost because the "
						 "server took too long to respond. The server "
						 "may be very busy or you may have a network"),
					       host.get());
	}
	else if (strcmp (aError, "malformedURI") == 0)
	{
		*aPrimary = g_strdup (_("Invalid address"));
		*aSecondary = g_strdup (_("The address you entered is not valid."));
	}
	else if (strcmp (aError, "redirectLoop") == 0)
	{
		*aPrimary = g_strdup (_("Too many redirects"));
		*aSecondary = g_strdup_printf (_("The server redirected too many times. "
						 "The redirection has been stopped for "
						 "security reasons."));
	}
	else if (strcmp (aError, "unknownSocketType") == 0)
	{
		*aPrimary = g_strdup (_("The document could not be loaded"));
		*aSecondary = g_strdup (_("This document requires \"Personal "
					  "Security Manager\" to be installed."));
	}
	else if (strcmp (aError, "netReset") == 0)
	{
		*aPrimary = g_strdup (_("Connection dropped by server"));
		*aSecondary = g_strdup (_("Epiphany connected to the server, "
					  "but the server dropped the connection "
					  "before any data could be read."));
	}
	else if (strcmp (aError, "netOffline") == 0)
	{
		*aPrimary = g_strdup (_("Cannot load document in offline mode"));
		*aSecondary = g_strdup (_("This document cannot be viewed in offline "
					  "mode. Set Epiphany to \"online\" and try "
					  "again."));
	}
	else if (strcmp (aError, "deniedPortAccess") == 0)
	{
		*aPrimary = g_strdup (_("FIXME"));
		*aSecondary = g_strdup (_("FIXME"));
	}
	else if (strcmp (aError, "proxyResolveFailure") == 0 ||
		 strcmp (aError, "proxyConnectFailure") == 0)
	{
		*aPrimary = g_strdup (_("Could not connect to proxy server"));
		*aSecondary = g_strdup (_("Check you system wide proxy server settings. "
					  "If the connection still fails, there may be "
					  "a problem with your proxy server or your "
					  "network connection."));
	}
	else
	{
		return NS_ERROR_ILLEGAL_VALUE;
	}

	return NS_OK;
}

nsresult
EphyProtocolHandler::HandleEpiphany(nsIURI *aErrorURI,
				     nsIChannel **_retval)
{
	NS_ENSURE_ARG (aErrorURI);

	nsCAutoString spec;
	aErrorURI->GetSpec (spec);

	if (g_str_has_prefix (spec.get(), "epiphany:error?"))
	{
		return CreateErrorPage (aErrorURI, _retval);
	}

	return NS_ERROR_ILLEGAL_VALUE;
}

nsresult
EphyProtocolHandler::CreateErrorPage(nsIURI *aErrorURI,
				     nsIChannel **_retval)
{
        /* First parse the arguments */
        nsresult rv = NS_ERROR_ILLEGAL_VALUE;
        nsCAutoString spec;
	rv = aErrorURI->GetSpec (spec);
	NS_ENSURE_TRUE (NS_SUCCEEDED (rv) && !spec.IsEmpty(), rv);

	nsCAutoString error, url, charset;
	rv = ParseErrorURL (spec.get (), error, url, charset);
	if (NS_FAILED (rv) || error.IsEmpty () || url.IsEmpty()) return rv;

	nsCOMPtr<nsIURI> uri;
	rv = EphyUtils::NewURI(getter_AddRefs (uri), url, charset.get());
	/* FIXME can uri be NULL if the original url was invalid? */
	NS_ENSURE_TRUE (NS_SUCCEEDED (rv) && uri, rv);

	char *primary = NULL, *secondary = NULL;
	rv = GetErrorMessage (uri, error.get(), &primary, &secondary);

	/* we don't know about this error code; forward to mozilla's impl */
	if (rv == NS_ERROR_ILLEGAL_VALUE)
	{
		nsCAutoString url(spec);

		/* remove "epiphany:error" part and insert mozilla's error page url */
		url.Cut(0, strlen ("epiphany:error"));
		url.Insert("chrome://global/content/netError.xhtml", 0);

		return Redirect (url, _retval);
	}

	NS_ENSURE_TRUE (primary && secondary, NS_ERROR_FAILURE);

	/* open the rendering stream */
	nsCOMPtr<nsIStorageStream> storageStream;
	rv = NS_NewStorageStream(16384, (PRUint32) -1, getter_AddRefs (storageStream));
	NS_ENSURE_SUCCESS (rv, rv);

	nsCOMPtr<nsIOutputStream> stream;
	rv = storageStream->GetOutputStream(0, getter_AddRefs (stream));
	NS_ENSURE_SUCCESS (rv, rv);

	char *language = g_strdup (pango_language_to_string (gtk_get_default_language ()));
	g_strdelimit (language, "_-@", '\0');

	Write (stream,
	       "<?xml version=\"1.0\" encoding=\"utf-8\"?>\n"
	       "<!DOCTYPE html PUBLIC \"-//W3C//DTD XHTML 1.0 Strict//EN\" "
	       "\"http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd\">\n"
	       "<html xmlns=\"http://www.w3.org/1999/xhtml\" lang=\"");
	Write (stream, language);
	Write (stream,
	       "\" xml:lang=\"");
	Write (stream, language);
	Write (stream,
	       "\">\n"
	       "<head>\n"
		"<title>");
	WriteHTMLEscape (stream, primary);
	/* no favicon for now, it would pollute the favicon cache */
	/* "<link rel=\"icon\" type=\"image/png\" href=\"moz-icon://stock/gtk-dialog-error?size=16\" />\n" */
	Write (stream,
		"</title>\n"
		"<style type=\"text/css\">\n"
		"html {\n"
			"background-color: white;\n"
			"color: WindowText;\n"
		"}\n"

		"body {\n"
			"background-color: Window;\n"
			"border: 1px solid black;\n"
			"margin: 12px;\n"
			"padding: 12px 12px 12px 72px;\n"
		"}\n"

		"h1 {\n"
			"margin: 0;\n"
			"font-size: 1.2em;\n"
			"font-weight: bold;\n"
		"}\n"

		"div#img {\n"
			"position: absolute;\n"
			"top: 25px;\n"
			"left: 25px;\n"
		"}\n"

		"p {\n"
			"margin: 1em 0 0;\n"
		"}\n"
		"</style>\n"
	       "</head>\n"
	       "<body dir=\"");
	Write (stream,
	       gtk_widget_get_default_direction () == GTK_TEXT_DIR_RTL ? "rtl" : "ltr");
	Write (stream,
	       "\">\n"
		"<div id=\"img\"><img src=\"moz-icon://stock/gtk-dialog-error?size=dialog\" alt=\"");

	/* get alt text */
	GtkStockItem item;
	if (gtk_stock_lookup (GTK_STOCK_DIALOG_ERROR, &item) && item.label)
	{
		WriteHTMLEscape (stream, item.label);
	}

	Write (stream,
		")\" /></div>\n"
		"<div id=\"text\">\n"
		"<h1>");
	WriteHTMLEscape (stream, primary);
	Write (stream,
	       "</h1>\n"
	       "<p>");
	WriteHTMLEscape (stream, secondary);
	Write (stream,
		"</p>\n"
		"</div>\n"
	       "</body>\n"
	       "</html>\n");

	g_free (language);
	g_free (primary);
	g_free (secondary);
 
	/* finish the rendering */
	nsCOMPtr<nsIInputStream> inputStream;
	rv = storageStream->NewInputStream(0, getter_AddRefs (inputStream));
	NS_ENSURE_SUCCESS (rv, rv);

	nsCOMPtr<nsIInputStreamChannel> channel (do_CreateInstance (kInputStreamChannelCID, &rv));
	NS_ENSURE_SUCCESS (rv, rv);

	rv |= channel->SetURI (aErrorURI);
	rv |= channel->SetContentStream (inputStream);
	rv |= channel->SetContentType (NS_LITERAL_CSTRING ("application/xhtml+xml"));
	rv |= channel->SetContentCharset (NS_LITERAL_CSTRING ("utf-8"));
	NS_ENSURE_SUCCESS (rv, rv);

	nsCOMPtr<nsIScriptSecurityManager> securityManager 
		(do_GetService(NS_SCRIPTSECURITYMANAGER_CONTRACTID, &rv));
	NS_ENSURE_SUCCESS (rv, rv);

	nsCOMPtr<nsIPrincipal> principal;
	rv = securityManager->GetCodebasePrincipal (aErrorURI, getter_AddRefs (principal));
	NS_ENSURE_SUCCESS (rv, rv);

	rv = channel->SetOwner(principal);
	NS_ENSURE_SUCCESS (rv, rv);

	NS_ADDREF(*_retval = channel);
	return rv;
}

nsresult
EphyProtocolHandler::Write(nsIOutputStream *aStream,
			   const char *aText)
{
	PRUint32 bytesWritten;
	return aStream->Write (aText, strlen (aText), &bytesWritten);
}

nsresult
EphyProtocolHandler::WriteHTMLEscape(nsIOutputStream *aStream,
				     const char *aText)
{
	char *text = g_markup_escape_text (aText, strlen (aText));
	nsresult rv = Write (aStream, text);
	g_free (text);

	return rv;
}