/*
 * This file is a part of Winix
 * and is distributed under the 2-Clause BSD licence.
 * Author: Tomasz Sowa <t.sowa@ttmath.org>
 */

/* 
 * Copyright (c) 2008-2022, Tomasz Sowa
 * All rights reserved.
 * 
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 * 
 * 1. Redistributions of source code must retain the above copyright notice,
 * this list of conditions and the following disclaimer.
 * 
 * 2. Redistributions in binary form must reproduce the above copyright
 * notice, this list of conditions and the following disclaimer in the
 * documentation and/or other materials provided with the distribution.
 * 
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 * 
 */
 
#ifndef headerfile_winix_core_request
#define headerfile_winix_core_request

#include <fcgiapp.h>
#include <sstream>
#include <vector>
#include "requesttypes.h"
#include "models/item.h"
#include "error.h"
#include "config.h"
#include "textstream.h"
#include "templates/htmltextstream.h"
#include "date/date.h"
#include "space/space.h"
#include "textstream/textstream.h"
#include "outstreams.h"
#include "models.h"
#include "models/winixmodel.h"
#include "header.h"
#include "compress.h"
#include "plugin.h"
#include "mount.h"
#include "mounts.h"
#include "jobtask.h"



namespace Winix
{




class FunctionBase;
class Templates;



class Request : public WinixModel
{
public:


	// how many input headers can be put to in_headers struct
	static const size_t MAX_INPUT_HEADERS = 32;

	// how many characters there can be in one header name
	static const size_t INPUT_HEADER_NAME_MAX_LENGTH = 64;

	// how many characters there can be in one header value
	static const size_t INPUT_HEADER_VALUE_MAX_LENGTH = 8192;


	/*
		request id
		is incremented for each request and is never 0
		(from -1 will be incremented to one)
		it's used for some optimizations e.g. in templates
	*/
	size_t id;

	// the state of the request
	//   not_assigned - the object is not being used
	//   normal_run - run in the main thread, this state is set after a new request is made
	//   assigned_to_job - the request is preserved and a new job will be called
	//   job_run - run in the job thread (objects are locked)
	//   finished - the request is finished and the object can be removed
	enum RunState { not_assigned = 0, normal_run, assigned_to_job, job_run, job_continuation_run, prepare_to_finish, finished};

	RunState run_state;

	/*
	 * request start time
	 *
	 * start_time is the same as timespec_req_start.tv_sec
	 * start_date is a pt::Date converted from start_time
	 *
	 */
	timespec timespec_req_start;
	time_t   start_time;
	pt::Date start_date;


	/*
	 * request stop time
	 *
	 */
	timespec timespec_req_stop;


	/*
	 * request stop time - start time
	 *
	 */
	timespec timespec_req_diff;


	/*
	 * start time of the ezc engine (html templates)
	 *
	 */
	timespec timespec_ezc_engine_start;


	/*
	 * end time of the ezc engine (html templates)
	 *
	 */
	timespec timespec_ezc_engine_stop;






	/*
	 *
	 *
	 *
	 * variables representing input from client's browser
	 *
	 *
	 *
	*/

	/*
		the HTTP method
		!! IMPROVE ME add the rest methods here
	*/
	enum Method { get, head, post, put, delete_, connect, options, trace, patch, unknown_method } method;


	/*
		subdomain
		subdomain = HTTP_HOST environment variable - config->base_url
	*/
	std::wstring subdomain;


	/*
		raw parameters
		!! CHECK ME may post_tab and cookie_tab should be changed to pt::Space now?
		or may change the name to cookie_in? or in_cookie?
	*/
	PostFileTab post_file_tab;
	CookieTab   cookie_tab;
	pt::Space	post_in;

	// input headers (without cookies)
	// at the moment we are using FastCGI and HTTP headers are prefixed with 'HTTP_' string
	// so we drop the prefix and change all characters to small ones

	// although https://www.w3.org/Protocols/rfc2616/rfc2616-sec4.html#sec4.2 says that there can be more
	// than one http header with the same name we do not support it
	// each header has a different name here, cookies we have in a different container (cookie_tab)
	pt::Space headers_in;


	/*
		html anchor (those part of URI after '#' character)
	*/
	std::wstring anchor;


	// environment variables
	std::wstring env_request_method;
	std::wstring env_request_uri;
	std::wstring env_http_cookie;
	std::wstring env_http_host;
	std::wstring env_http_user_agent;
	std::wstring env_http_accept_encoding;
	std::wstring env_http_accept;
	std::wstring env_http_accept_language;
	std::wstring env_fcgi_role;
	std::wstring env_content_type;
	std::wstring env_https;

	// current IP address of the remote host
	// (read either from REMOTE_ADDR environment variable or from config.proxy_ip_header HTTP variable if config.check_proxy_ip_header is set to true)
	// (at the moment only IPv4 are supported)
	int ip;
	std::wstring ip_str; // ip_str can be ipv6 now


	// true if the browser is Microsoft Internet Explorer
	bool browser_msie;

    // true if the browser is Konqueror
    bool browser_konqueror;

	// true if we are using an encrypted connection (SSL)
	bool using_ssl;

	// true if the request is being made by ajax by htmx library
	bool is_htmx_request;

	/*
		request input variables representing the winix filesystem
	*/

	// current directory
	std::vector<Item*> dir_tab;

	// true if a file exists
	bool is_item;

	// current file (valid if is_item is true)
	Item item;

	// current winix function
	// null if there is no a function
	FunctionBase * function;

	// current session (if exists, can be null)
	Session * session;

	// current mount point (can be null, it is treated as cms filesystem then)
	Mount * mount;

	// parameters (name:value)
	ParamTab param_tab;

	// this is a pointer either to the item (if exists) or to the last directory
	Item * last_item;

	// can we use gzip compression algorithm when sending content to the client
	bool accept_gzip;

	// can we use deflate compression algorithm when sending content to the client
	bool accept_deflate;


	/*
	 *
	 *
	 *
	 * variables for generating output to the client's browser
	 *
	 *
	 *
	*/

	//
	// the algorithm how a request's container is selected is shown below:
	// (the whole answer's algorightm is implemented in PrepareAnswerType() method)
	// ------------------------------------------------------------------------------------------
	//
	// at the beginning we set container_type to "raw" meaning simple text or html, then
	// we check the "Accept" http header, if it is set then we set container_type accordingly:
	//
	//     	                Accept | container_type
	//     	-----------------------------------------------
	//     	             text/html | container_raw
	//     	 application/xhtml+xml | container_raw
	//     	      application/json | container_json
	//     	       application/xml | container_xml
	//     	              text/csv | container_csv
	//
	// next we check "container" url parameter, if it is set then we set container_type accordingly
	// ("container" url parameter has higher precedence than "Accept" http header):
	//
	//                   container | container_type
	//      -----------------------------------------------
	//                        raw | container_raw
	//                       json | container_json
	//                        xml | container_xml
	//                        csv | container_csv
	//
	//
	// Samples:
	//
	// http://domain.tld/dir/controller
	// returns html answer from the main ezc stream
	//
	// http://domain.tld/dir/controller/container:raw
	// returns html answer from the main ezc stream (the same as above)
	//
	// http://domain.tld/dir/controller/frame:abc
	// returns "abc" frame as html
	//
	// http://domain.tld/dir/controller/container:json
	// returns all serialized models to json and no ezc streams
	//
	// http://domain.tld/dir/controller/container:xml
	// returns all serialized models to xml and no ezc streams
	//
	// http://domain.tld/dir/controller/container:json/frame:abc,xyz
	// returns all serialized models to json and two frames in 'ezc_frames' object
	//
	// http://domain.tld/dir/controller/container:json/all_frames
	// returns all serialized models to json and all frames in 'ezc_frames' object
	//
	// http://domain.tld/dir/controller/container:json/main_stream
	// returns all serialized models and the main ezc stream in 'main_stream' field
	//
	// http://domain.tld/dir/controller/container:json/main_stream/all_frames
	// returns all serialized models to json, all frames and the main stream
	//


	bool send_bin_stream;
	bool send_main_stream;
	bool send_all_frames;
	std::vector<std::wstring> send_frames;

	bool use_ezc_engine;
	bool serialize_models;


	// change maybe answer_text -> container_text?
	enum ContainerType
	{
		container_raw,
		container_json,
		container_xml,
		container_csv,
	};

	ContainerType container_type;


	// at the beginning those with higher priority
	std::vector<HeaderValue> accept_mime_types;

	// at the beginning those with higher priority
	std::vector<HeaderValue> accept_languages;

	// request status
	// DEPRECATED, use http_status instead
	Error status;

	/*
	 * HTTP result status
	 * at the moment default is -1 which means it is not used (use status in such a case)
	 */
	int http_status;

	// if not empty means an address for redirecting to
	// it should be url-encoded
	std::wstring redirect_to;

	// a redirect type
	// following redirect types are supported:
	// 300 Multiple Choices
	// 301 Moved Permanently
	// 302 Found
	// 303 See Other (default)
	// 307 Temporary Redirect
	int redirect_type;

	// send header X-LIGHTTPD-send-file with path to a file
	std::wstring x_sendfile;

	// send as attachment (causes generating header: content-disposition: attachment)
	bool send_as_attachment;

	// headers send to the client (without cookies) (may change to headers_out?)
	pt::Space out_headers;

	// cookies send to the client
	// a value can be either a cookie value or the whole cookie string (with domain, date etc)
	pt::Space out_cookies;


	// binary page sent to the client if answer_source is answer_bin_stream
	BinaryPage out_bin_stream;

	// main text output stream where the html otput is generated from ezc templates
	// here the whole html page (with doctype, head, body) is generated
	HtmlTextStream out_main_stream;

	// text output streams used in ajax requests
	// in ezc templates you can use [ezc frame "stream_name"] or just [frame "stream_name"] keyword
	// to switch between streams
	Ezc::OutStreams<HtmlTextStream, true> out_streams;

	// models to return or to render through ezc library
	Ezc::Models models;

	// filter html content with HTMLFilter, default the same as config.html_filter
	bool use_html_filter;
	
	// if this variable is true then winix always return 200 OK header
	// when the status would be 404 (not found) or 403 (permission denied)
	// default: false
	bool use_200_status_for_not_found_and_permission_denied;

	// options used by ezc generators
	bool gen_trim_white;
	bool gen_skip_new_line;
	bool gen_use_special_chars;

	// index template name
	std::wstring html_template;


	/*
		additional variables used for common uses
	*/

	// DEPRECATED will be removed
	// usually items in the current directory (depends on the function)
	std::vector<Item> item_tab;


	/*
	 * FastCGI request structure with pointers to input/output streams
	 */
	FCGX_Request fcgi_request;


	long job_id; // the main id of your job
	long job_second_id; // a secondary id of your job
	pt::Space job;



	Request();

	void SetConfig(Config * config);
	void SetTemplates(Templates * templates);
	void SetCompress(Compress * compress);
	void SetPlugin(Plugin * plugin);
	void SetMounts(Mounts * mounts);


	void fields();


	void RequestStarts();
	void RequestEnds();
	void Clear();

	void PrepareAnswerType();

	bool IsParam(const wchar_t * param_name);
	bool IsParam(const std::wstring & param_name);
	const std::wstring & ParamValue(const wchar_t * param_name);      // returns an empty string if there is no such a parameter
	const std::wstring & ParamValue(const std::wstring & param_name); // returns an empty string if there is no such a parameter

	std::wstring * ParamValuep(const wchar_t * param_name);           // returns nullptr if there is no such a parameter
	std::wstring * ParamValuep(const std::wstring & param_name);      // returns nullptr if there is no such a parameter

	void AddParam(const std::wstring & param_name, const std::wstring & param_value);
	void AddParam(const wchar_t * param_name, const wchar_t * param_value);

	void RemoveParam(const wchar_t * param_name);
	void RemoveParam(const std::wstring & param_name);

	pt::Space * AddPostVar(pt::Space & space, const wchar_t * name);
	bool AddPostVar(const wchar_t * name, const wchar_t * value);
	bool AddPostVar(const std::wstring & name, const std::wstring & value);

	bool IsPostVar(const wchar_t * var);
	bool IsPostVar(const std::wstring & var);
	const std::wstring & PostVar(const wchar_t * var);				// returns an empty string if there is no such a parameter
	const std::wstring & PostVar(const std::wstring & var);			// returns an empty string if there is no such a parameter
	bool PostVar(const wchar_t * var, std::wstring & result);
	bool PostVar(const std::wstring & var, std::wstring & result);
	std::wstring * PostVarp(const wchar_t * var);
	std::wstring * PostVarp(const std::wstring & var);

	void AddCookie(
			const std::wstring & name,
			const std::wstring * value_string = nullptr,
			const pt::Stream * value_stream = nullptr,
			pt::Date * expires = nullptr,
			const std::wstring * path = nullptr,
			const std::wstring * domain = nullptr,
			CookieSameSite cookie_same_site = CookieSameSite::samesite_notset,
			bool http_only = false,
			bool secure = false);

	void AddDefaultSessionCookie(const std::wstring & value, pt::Date * expires = nullptr);

	bool has_frame(const wchar_t * frame);
	bool has_frame(const std::wstring & frame);

	void create_job(long job_id = JobTask::JOB_ID_DEFAULT, long job_secondary_id = JobTask::JOB_ID_DEFAULT);
	void modify_status_code_if_needed();

	// RENAMEME to add_header_if_not_exists
	bool AddHeader(const wchar_t * name, const wchar_t * value);
	bool AddHeader(const wchar_t * name, long value);
	bool AddHeader(const std::wstring & name, const std::wstring & value);
	bool AddHeader(const wchar_t * name, const pt::WTextStream & value);
	bool AddHeader(const std::wstring & name, const pt::WTextStream & value);

	void FinishRequest();


	void SetEnv(const char * name, std::wstring & env);
	void ReadEnvVariables();
	void ReadEnvRemoteIP();

	static Method CheckRequestMethod(const wchar_t * name);
	void CheckRequestMethod();

	void CheckSSL();
	void SetSubdomain();

	static void PutMethodName(Request::Method method, pt::Stream & stream);
	void PutMethodName(pt::Stream & stream);

private:

	Config * config;
	Templates * templates;
	Compress * compress;
	Plugin * plugin;
	Mounts * mounts;

	BinaryPage output_8bit;
	BinaryPage compressed_output;
	pt::WTextStream output_tmp_filtered_stream;
	pt::TextStream serialized_model;
	std::string aheader_name, aheader_value;
	std::wstring cookie_id_string;
	std::string send_data_buf;
	std::wstring http_header_name;
	std::string http_header_8bit;



	// used in ParamValue() and PostVar() when there is no such a param
	const std::wstring str_empty;

	void ClearOutputStreams();

	void CheckAcceptHeader();
	void CheckContainerParameter();
	void PrepareFrameNames();

	void current_dir(morm::Wrapper & wrapper);
	void last_item_wrapper(morm::Wrapper & wrapper);

	void http_status_error_title(EzcEnv & env);
	void http_status_error_description(EzcEnv & env);

	void PrepareAndSendAnswer();
	void PrepareRawAnswer();
	void PrepareJsonAnswer();
	void PrepareXmlAnswer();
	void PrepareCsvAnswer();
	void PrepareContenerizedAnswer();
	void PutSeparatorIfNeeded(bool put_separator);
	void SerializeFieldJson(const wchar_t * field_name);
	void SerializeStream(const pt::WTextStream & input_stream, const wchar_t * field_name);
	void SerializeStreamJson(const pt::WTextStream & input_stream, const wchar_t * field_name);
	void SerializeStreamXml(const pt::WTextStream & input_stream, const wchar_t * field_name);
	void SerializeStreamCsv(const pt::WTextStream & input_stream, const wchar_t * field_name);
	void SerializeAllFrames();
	void SerializeSpecificFrames();
	void SerializeModels();
	void SerializeModel(morm::Wrapper & wrapper, const wchar_t * field_name);
	void SerializeModelJson(morm::Wrapper & wrapper, const wchar_t * field_name);
	void SerializeModelXml(morm::Wrapper & wrapper, const wchar_t * field_name);
	void SerializeModelCsv(morm::Wrapper & wrapper, const wchar_t * field_name);
	void FilterHtmlIfNeeded(const pt::WTextStream & input_stream, BinaryPage & output, bool clear_stream = true);
	void Send8bitOutput(BinaryPage & output);
	void SendData(const BinaryPage & page, FCGX_Stream * out);
	void UseEzcGenerator();
	int SelectDeflateVersion();
	void SelectCompression(size_t source_len, bool & compression_allowed, int & compression_encoding);
	void PrepareSessionCookie();
	void PrepareHeaders(bool compressing, int compress_encoding, size_t output_size);
	void ModifyStatusForRedirect();
	void PrepareSendFileHeaderForStaticMountpoint();
	void PrepareSendFileHeader();
	void PrepareContentEncodingHeader(int compress_encoding);
	void PrepareContentLengthHeader(size_t output_size);
	void PrepareHeaderContentType();
	void PrepareHeaderStatus(int http_status);
	void SendHeaders();
	void SendCookies();
	bool CreateStaticResourcePath(pt::WTextStream & out_path);
	bool CanSendContent();
	void LogRequestTime();

	MORM_MEMBER_FIELD(Request)

};



} // namespace Winix

#endif