// --------------------------------------------------------------------------
//
// File
//		Name:    HTTPResponse.cpp
//		Purpose: Response object for HTTP connections
//		Created: 26/3/04
//
// --------------------------------------------------------------------------

#include "Box.h"

#include <stdio.h>
#include <string.h>

#include "HTTPResponse.h"
#include "autogen_HTTPException.h"

#include "MemLeakFindOn.h"

// Static variables
std::string HTTPResponse::msDefaultURIPrefix;


// --------------------------------------------------------------------------
//
// Function
//		Name:    HTTPResponse::HTTPResponse()
//		Purpose: Constructor
//		Created: 26/3/04
//
// --------------------------------------------------------------------------
HTTPResponse::HTTPResponse()
	: mResponseCode(HTTPResponse::Code_NoContent),
	  mResponseIsDynamicContent(true),
	  mKeepAlive(false)
{
}


// --------------------------------------------------------------------------
//
// Function
//		Name:    HTTPResponse::~HTTPResponse()
//		Purpose: Destructor
//		Created: 26/3/04
//
// --------------------------------------------------------------------------
HTTPResponse::~HTTPResponse()
{
}


// --------------------------------------------------------------------------
//
// Function
//		Name:    HTTPResponse::ResponseCodeToString(int)
//		Purpose: Return string equivalent of the response code, suitable for Status: headers
//		Created: 26/3/04
//
// --------------------------------------------------------------------------
const char *HTTPResponse::ResponseCodeToString(int ResponseCode)
{
	switch(ResponseCode)
	{
	case Code_OK: return "200 OK"; break;
	case Code_NoContent: return "204 No Content"; break;
	case Code_MovedPermanently: return "301 Moved Permanently"; break;
	case Code_Found: return "302 Found"; break;
	case Code_NotModified: return "304 Not Modified"; break;
	case Code_TemporaryRedirect: return "307 Temporary Redirect"; break;
	case Code_Unauthorized: return "401 Unauthorized"; break;
	case Code_Forbidden: return "403 Forbidden"; break;
	case Code_NotFound: return "404 Not Found"; break;
	case Code_InternalServerError: return "500 Internal Server Error"; break;
	case Code_NotImplemented: return "501 Not Implemented"; break;
	default:
		{
			THROW_EXCEPTION(HTTPException, UnknownResponseCodeUsed)
		}
	}
	return "500 Internal Server Error";
}


// --------------------------------------------------------------------------
//
// Function
//		Name:    HTTPResponse::SetResponseCode(int)
//		Purpose: Set the response code to be returned
//		Created: 26/3/04
//
// --------------------------------------------------------------------------
void HTTPResponse::SetResponseCode(int Code)
{
	mResponseCode = Code;
}


// --------------------------------------------------------------------------
//
// Function
//		Name:    HTTPResponse::SetContentType(const char *)
//		Purpose: Set content type
//		Created: 26/3/04
//
// --------------------------------------------------------------------------
void HTTPResponse::SetContentType(const char *ContentType)
{
	mContentType = ContentType;
}


// --------------------------------------------------------------------------
//
// Function
//		Name:    HTTPResponse::Send(IOStream &, bool)
//		Purpose: Build the response, and send via the stream. Optionally omitting
//				 the content.
//		Created: 26/3/04
//
// --------------------------------------------------------------------------
void HTTPResponse::Send(IOStream &rStream, bool OmitContent)
{
	if(mContentType.empty())
	{
		THROW_EXCEPTION(HTTPException, NoContentTypeSet)
	}

	// Build and send header
	{
		std::string header("HTTP/1.1 ");
		header += ResponseCodeToString(mResponseCode);
		header += "\r\nContent-Type: ";
		header += mContentType;
		header += "\r\nContent-Length: ";
		{
			char len[32];
			::sprintf(len, "%d", OmitContent?(0):(GetSize()));
			header += len;
		}
		// Extra headers...
		for(std::vector<std::string>::const_iterator i(mExtraHeaders.begin()); i != mExtraHeaders.end(); ++i)
		{
			header += "\r\n";
			header += *i;
		}
		// NOTE: a line ending must be included here in all cases
		// Control whether the response is cached
		if(mResponseIsDynamicContent)
		{
			// dynamic is private and can't be cached
			header += "\r\nCache-Control: no-cache, private";
		}
		else
		{
			// static is allowed to be cached for a day
			header += "\r\nCache-Control: max-age=86400";
		}
		if(mKeepAlive)
		{
			header += "\r\nConnection: keep-alive\r\n\r\n";
		}
		else
		{
			header += "\r\nConnection: close\r\n\r\n";
		}
		// NOTE: header ends with blank line in all cases
		
		// Write to stream
		rStream.Write(header.c_str(), header.size());
	}
	
	// Send content
	if(!OmitContent)
	{
		rStream.Write(GetBuffer(), GetSize());
	}
}


// --------------------------------------------------------------------------
//
// Function
//		Name:    HTTPResponse::AddHeader(const char *)
//		Purpose: Add header, given entire line
//		Created: 26/3/04
//
// --------------------------------------------------------------------------
void HTTPResponse::AddHeader(const char *EntireHeaderLine)
{
	mExtraHeaders.push_back(std::string(EntireHeaderLine));
}


// --------------------------------------------------------------------------
//
// Function
//		Name:    HTTPResponse::AddHeader(const std::string &)
//		Purpose: Add header, given entire line
//		Created: 26/3/04
//
// --------------------------------------------------------------------------
void HTTPResponse::AddHeader(const std::string &rEntireHeaderLine)
{
	mExtraHeaders.push_back(rEntireHeaderLine);
}


// --------------------------------------------------------------------------
//
// Function
//		Name:    HTTPResponse::AddHeader(const char *, const char *)
//		Purpose: Add header, given header name and it's value
//		Created: 26/3/04
//
// --------------------------------------------------------------------------
void HTTPResponse::AddHeader(const char *Header, const char *Value)
{
	std::string h(Header);
	h += ": ";
	h += Value;
	mExtraHeaders.push_back(h);
}


// --------------------------------------------------------------------------
//
// Function
//		Name:    HTTPResponse::AddHeader(const char *, const std::string &)
//		Purpose: Add header, given header name and it's value
//		Created: 26/3/04
//
// --------------------------------------------------------------------------
void HTTPResponse::AddHeader(const char *Header, const std::string &rValue)
{
	std::string h(Header);
	h += ": ";
	h += rValue;
	mExtraHeaders.push_back(h);
}


// --------------------------------------------------------------------------
//
// Function
//		Name:    HTTPResponse::AddHeader(const std::string &, const std::string &)
//		Purpose: Add header, given header name and it's value
//		Created: 26/3/04
//
// --------------------------------------------------------------------------
void HTTPResponse::AddHeader(const std::string &rHeader, const std::string &rValue)
{
	mExtraHeaders.push_back(rHeader + ": " + rValue);
}


// --------------------------------------------------------------------------
//
// Function
//		Name:    HTTPResponse::SetCookie(const char *, const char *, const char *, int)
//		Purpose: Sets a cookie, using name, value, path and expiry time.
//		Created: 20/8/04
//
// --------------------------------------------------------------------------
void HTTPResponse::SetCookie(const char *Name, const char *Value, const char *Path, int ExpiresAt)
{
	if(ExpiresAt != 0)
	{
		THROW_EXCEPTION(HTTPException, NotImplemented)
	}

	// Appears you shouldn't use quotes when you generate set-cookie headers.
	// Oh well. It was fun finding that out.
/*	std::string h("Set-Cookie: ");
	h += Name;
	h += "=\"";
	h += Value;
	h += "\"; Version=\"1\"; Path=\"";
	h += Path;
	h += "\"";
*/
	std::string h("Set-Cookie: ");
	h += Name;
	h += "=";
	h += Value;
	h += "; Version=1; Path=";
	h += Path;

	mExtraHeaders.push_back(h);
}


// --------------------------------------------------------------------------
//
// Function
//		Name:    HTTPResponse::SetAsRedirect(const char *, bool)
//		Purpose: Sets the response objects to be a redirect to another page.
//				 If IsLocalURL == true, the default prefix will be added.
//		Created: 26/3/04
//
// --------------------------------------------------------------------------
void HTTPResponse::SetAsRedirect(const char *RedirectTo, bool IsLocalURI)
{
	if(mResponseCode != HTTPResponse::Code_NoContent
		|| !mContentType.empty()
		|| GetSize() != 0)
	{
		THROW_EXCEPTION(HTTPException, CannotSetRedirectIfReponseHasData)
	}

	// Set response code
	mResponseCode = Code_Found;

	// Set location to redirect to
	std::string header("Location: ");
	if(IsLocalURI) header += msDefaultURIPrefix;
	header += RedirectTo;
	mExtraHeaders.push_back(header);
	
	// Set up some default content
	mContentType = "text/html";
	#define REDIRECT_HTML_1 "<html><head><title>Redirection</title></head>\n<body><p><a href=\""
	#define REDIRECT_HTML_2 "\">Redirect to content</a></p></body></html>\n"
	Write(REDIRECT_HTML_1, sizeof(REDIRECT_HTML_1) - 1);
	if(IsLocalURI) Write(msDefaultURIPrefix.c_str(), msDefaultURIPrefix.size());
	Write(RedirectTo, ::strlen(RedirectTo));
	Write(REDIRECT_HTML_2, sizeof(REDIRECT_HTML_2) - 1);
}


// --------------------------------------------------------------------------
//
// Function
//		Name:    HTTPResponse::SetAsNotFound(const char *)
//		Purpose: Set the response object to be a standard page not found 404 response.
//		Created: 7/4/04
//
// --------------------------------------------------------------------------
void HTTPResponse::SetAsNotFound(const char *URI)
{
	if(mResponseCode != HTTPResponse::Code_NoContent
		|| mExtraHeaders.size() != 0
		|| !mContentType.empty()
		|| GetSize() != 0)
	{
		THROW_EXCEPTION(HTTPException, CannotSetNotFoundIfReponseHasData)
	}

	// Set response code
	mResponseCode = Code_NotFound;

	// Set data
	mContentType = "text/html";
	#define NOT_FOUND_HTML_1 "<html><head><title>404 Not Found</title></head>\n<body><h1>404 Not Found</h1>\n<p>The URI <i>"
	#define NOT_FOUND_HTML_2 "</i> was not found on this server.</p></body></html>\n"
	Write(NOT_FOUND_HTML_1, sizeof(NOT_FOUND_HTML_1) - 1);
	WriteStringDefang(std::string(URI));
	Write(NOT_FOUND_HTML_2, sizeof(NOT_FOUND_HTML_2) - 1);
}


// --------------------------------------------------------------------------
//
// Function
//		Name:    HTTPResponse::WriteStringDefang(const char *, unsigned int)
//		Purpose: Writes a string 'defanged', ie has HTML special characters escaped
//				 so that people can't output arbitary HTML by playing with
//				 URLs and form parameters, and it's safe to write strings into
//				 HTML element attribute values.
//		Created: 9/4/04
//
// --------------------------------------------------------------------------
void HTTPResponse::WriteStringDefang(const char *String, unsigned int StringLen)
{
	while(StringLen > 0)
	{
		unsigned int toWrite = 0;
		while(toWrite < StringLen 
			&& String[toWrite] != '<' 
			&& String[toWrite] != '>'
			&& String[toWrite] != '&'
			&& String[toWrite] != '"')
		{
			++toWrite;
		}
		if(toWrite > 0)
		{
			Write(String, toWrite);
			StringLen -= toWrite;
			String += toWrite;
		}
		
		// Is it a bad character next?
		while(StringLen > 0)
		{
			bool notSpecial = false;
			switch(*String)
			{
				case '<': Write("&lt;", 4); break;
				case '>': Write("&gt;", 4); break;
				case '&': Write("&amp;", 5); break;
				case '"': Write("&quot;", 6); break;
				default:
					// Stop this loop
					notSpecial = true;
					break;
			}
			if(notSpecial) break;
			++String;
			--StringLen;
		}
	}
}