/**
	This file is a part of r0nk, atlas_moon, and rexy's matrix client
	Copyright (C) 2019 rexy712

	This program is free software: you can redistribute it and/or modify
	it under the terms of the GNU Affero General Public License as published by
	the Free Software Foundation, either version 3 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 Affero General Public License for more details.

	You should have received a copy of the GNU Affero General Public License
	along with this program.  If not, see <http://www.gnu.org/licenses/>.
*/

#include "matrix/client_base.hpp"
#include "raii/rjp_ptr.hpp"
#include "raii/static_string.hpp"
#include <cstdlib> //size_t
#include <algorithm> //min, max

namespace matrix::internal{

	client_base::client_base(void):
		m_curl()
	{
		_set_curl_defaults(""_ss);
	}
	void client_base::_set_curl_useragent(const raii::string_base& useragent){
		m_curl.setuseragent(useragent);
	}
	size_t client_base::_post_reply_curl_callback(char* ptr, size_t size, size_t nmemb, void* userdata){
		raii::string* data = reinterpret_cast<raii::string*>(userdata);
		(*data) += ptr;
		return size*nmemb;
	}
	raii::string client_base::_get_curl(const raii::string_base& url)const{
		raii::string reply;
		m_curl.getreq();
		m_curl.seturl(url);
		m_curl.setheader(raii::curl_llist{});
		m_curl.setopt(CURLOPT_WRITEFUNCTION, _post_reply_curl_callback);
		m_curl.setopt(CURLOPT_WRITEDATA, &reply);
		CURLcode res = m_curl.perform();
		if(res != CURLE_OK)
			return {};
		return reply;
	}
	raii::string client_base::_post_curl(const raii::string_base& postdata, const raii::string_base& url, const raii::curl_llist& header)const{
		raii::string reply;
		m_curl.postreq();
		m_curl.setopt(CURLOPT_POSTFIELDS, postdata.get());
		m_curl.setopt(CURLOPT_POSTFIELDSIZE_LARGE, (curl_off_t)postdata.length());
		m_curl.seturl(url);
		m_curl.setheader(header);
		m_curl.setopt(CURLOPT_WRITEFUNCTION, _post_reply_curl_callback);
		m_curl.setopt(CURLOPT_WRITEDATA, &reply);
		CURLcode res = m_curl.perform();
		if(res != CURLE_OK)
			return {};
		return reply;
	}
	struct put_data{
		const char* data;
		size_t len;
	};
	static size_t _put_read_curl_callback(char* buffer, size_t size, size_t nmemb, void* userdata){
		put_data* src = reinterpret_cast<put_data*>(userdata);
		size_t curl_size = size*nmemb;
		size_t to_copy = std::min(curl_size, src->len);
		memcpy(buffer, src->data, to_copy);
		src->len -= to_copy;
		src->data += to_copy;
		return to_copy;
	}
	raii::string client_base::_put_curl(const raii::string_base& putdata, const raii::string_base& url, const raii::curl_llist& header)const{
		raii::string reply;
		put_data data{putdata.get(), putdata.length()};
		m_curl.putreq();
		m_curl.setopt(CURLOPT_POSTFIELDS, putdata.get());
		m_curl.setopt(CURLOPT_POSTFIELDSIZE_LARGE, (curl_off_t)putdata.length());
		m_curl.seturl(url);
		m_curl.setheader(header);
		m_curl.setopt(CURLOPT_WRITEFUNCTION, _post_reply_curl_callback);
		m_curl.setopt(CURLOPT_WRITEDATA, &reply);
		m_curl.setopt(CURLOPT_READFUNCTION, _put_read_curl_callback);
		m_curl.setopt(CURLOPT_READDATA, &data);
		m_curl.setopt(CURLOPT_INFILESIZE, (curl_off_t)data.len);
		CURLcode res = m_curl.perform();
		m_curl.setopt(CURLOPT_READDATA, NULL);
		m_curl.setopt(CURLOPT_READFUNCTION, NULL);
		if(res != CURLE_OK)
			return {};
		return reply;
	}
	raii::rjp_string client_base::_post_and_find(const raii::string_base& data, const raii::string_base& url,
	                                     const raii::curl_llist& header, const raii::string_base& target)const
	{
		raii::string reply = _post_curl(data, url, header);
		if(!reply)
			return {};
		return _curl_reply_search(reply, target);
	}
	raii::rjp_string client_base::_get_and_find(const raii::string_base& url, const raii::string_base& target)const{
		raii::string reply = _get_curl(url);
		if(!reply)
			return {};
		return _curl_reply_search(reply, target);
	}
	raii::rjp_string client_base::_curl_reply_search(const raii::string_base& reply, const raii::string_base& target)const{
		raii::rjp_ptr root(rjp_parse(reply));
		if(!root)
			return {};
		RJP_search_res res = rjp_search_member(root.get(), target.get(), 0);
		if(rjp_value_type(res.value) != json_string)
			return {};
		return raii::rjp_string(res.value);
	}
	void client_base::_set_curl_defaults(const raii::string_base& useragent)const{
		m_curl.setopt(CURLOPT_BUFFERSIZE, 102400L);
		m_curl.setopt(CURLOPT_NOPROGRESS, 1L);
		m_curl.setuseragent(useragent);
	m_curl.setopt(CURLOPT_MAXREDIRS, 50L);
		m_curl.setopt(CURLOPT_FOLLOWLOCATION, 1L);
		m_curl.forcessl(CURL_SSLVERSION_TLSv1_2);
		m_curl.setopt(CURLOPT_TCP_KEEPALIVE, 1L);
		m_curl.setopt(CURLOPT_FAILONERROR, 1L);
	}

}