//
//	License type: BSD 3-Clause License
//	License copy: https://github.com/Telecominfraproject/wlan-cloud-ucentralgw/blob/master/LICENSE
//
//	Created by Stephane Bourque on 2021-03-04.
//	Arilia Wireless Inc.
//

#include <iostream>

#include "Poco/CountingStream.h"
#include "Poco/DynamicAny.h"
#include "Poco/Exception.h"
#include "Poco/File.h"
#include "Poco/Net/HTTPServerParams.h"
#include "Poco/Net/HTTPServerResponse.h"
#include "Poco/Net/MessageHeader.h"
#include "Poco/Net/MultipartReader.h"
#include "Poco/Net/PartHandler.h"
#include "Poco/StreamCopier.h"
#include "Poco/StringTokenizer.h"

#include "framework/MicroServiceFuncs.h"
#include "framework/ow_constants.h"
#include "framework/utils.h"

#include "FileUploader.h"
#include "StorageService.h"
#include "fmt/format.h"

namespace OpenWifi {

	static const std::string URI_BASE{"/v1/upload/"};

	int FileUploader::Start() {
		poco_notice(Logger(), "Starting.");

		Poco::File UploadsDir(MicroServiceConfigPath("openwifi.fileuploader.path", "/tmp"));
		Path_ = UploadsDir.path();
		if (!UploadsDir.exists()) {
			try {
				UploadsDir.createDirectory();
			} catch (const Poco::Exception &E) {
				Logger().log(E);
				Path_ = "/tmp";
			}
		}

		for (const auto &Svr : ConfigServersList_) {
			if (MicroServiceNoAPISecurity()) {
				poco_notice(Logger(), fmt::format("Starting: {}:{}", Svr.Address(), Svr.Port()));

				auto Sock{Svr.CreateSocket(Logger())};

				auto Params = new Poco::Net::HTTPServerParams;
				Params->setMaxThreads(16);
				Params->setMaxQueued(100);
				Params->setName("ws:upldr");

				if (FullName_.empty()) {
					std::string TmpName =
						MicroServiceConfigGetString("openwifi.fileuploader.uri", "");
					if (TmpName.empty()) {
						FullName_ =
							"https://" + Svr.Name() + ":" + std::to_string(Svr.Port()) + URI_BASE;
					} else {
						FullName_ = TmpName + URI_BASE;
					}
					poco_information(Logger(), fmt::format("Uploader URI base is '{}'", FullName_));
				}

				auto NewServer = std::make_unique<Poco::Net::HTTPServer>(
					new FileUpLoaderRequestHandlerFactory(Logger()), Sock, Params);
				Params->setName("file-upldr");
				NewServer->start();
				Servers_.push_back(std::move(NewServer));
			} else {
				std::string l{"Starting: " + Svr.Address() + ":" + std::to_string(Svr.Port()) +
							  " key:" + Svr.KeyFile() + " cert:" + Svr.CertFile()};
				poco_information(Logger(), l);

				auto Sock{Svr.CreateSecureSocket(Logger())};

				Svr.LogCert(Logger());
				if (!Svr.RootCA().empty())
					Svr.LogCas(Logger());

				auto Params = new Poco::Net::HTTPServerParams;
				Params->setMaxThreads(16);
				Params->setMaxQueued(100);
				Params->setName("ws:upldr");

				if (FullName_.empty()) {
					std::string TmpName =
						MicroServiceConfigGetString("openwifi.fileuploader.uri", "");
					if (TmpName.empty()) {
						FullName_ =
							"https://" + Svr.Name() + ":" + std::to_string(Svr.Port()) + URI_BASE;
					} else {
						FullName_ = TmpName + URI_BASE;
					}
					poco_information(Logger(), fmt::format("Uploader URI base is '{}'", FullName_));
				}

				auto NewServer = std::make_unique<Poco::Net::HTTPServer>(
					new FileUpLoaderRequestHandlerFactory(Logger()), Sock, Params);
				NewServer->start();
				Servers_.push_back(std::move(NewServer));
			}
		}

		MaxSize_ = 1000 * MicroServiceConfigGetInt("openwifi.fileuploader.maxsize", 10000);

		return 0;
	}

	void FileUploader::reinitialize([[maybe_unused]] Poco::Util::Application &self) {
		MicroServiceLoadConfigurationFile();
		poco_information(Logger(), "Reinitializing.");
		Stop();
		Start();
	}

	const std::string &FileUploader::FullName() { return FullName_; }

	//  if you pass in an empty UUID, it will just clean the list and not add it.
	bool FileUploader::AddUUID(const std::string &UUID, std::chrono::seconds WaitTimeInSeconds,
							   const std::string &Type) {
		std::lock_guard Guard(Mutex_);

		uint64_t now = Utils::Now();
		auto Func = [now](const UploadId &I) -> bool { return (now > I.Expires); };
		OutStandingUploads_.erase(
			std::remove_if(OutStandingUploads_.begin(), OutStandingUploads_.end(), Func),
			OutStandingUploads_.end());
		OutStandingUploads_.emplace_back(UploadId{UUID, now + WaitTimeInSeconds.count(), Type});
		return true;
	}

	bool FileUploader::ValidRequest(const std::string &UUID) {
		std::lock_guard Guard(Mutex_);
		auto Func = [UUID](const UploadId &P) -> bool { return (P.UUID == UUID); };
		return std::find_if(OutStandingUploads_.begin(), OutStandingUploads_.end(), Func) !=
			   end(OutStandingUploads_);
	}

	void FileUploader::RemoveRequest(const std::string &UUID) {
		std::lock_guard Guard(Mutex_);
		auto Func = [UUID](const UploadId &P) -> bool { return (P.UUID == UUID); };
		OutStandingUploads_.erase(
			std::remove_if(OutStandingUploads_.begin(), OutStandingUploads_.end(), Func),
			OutStandingUploads_.end());
	}

	class FileUploaderPartHandler2 : public Poco::Net::PartHandler {
	  public:
		FileUploaderPartHandler2(std::string Id, Poco::Logger &Logger, std::stringstream &ofs)
			: Id_(std::move(Id)), Logger_(Logger), OutputStream_(ofs) {}
		void handlePart(const Poco::Net::MessageHeader &Header, std::istream &Stream) {
			FileType_ = Header.get(RESTAPI::Protocol::CONTENTTYPE, RESTAPI::Protocol::UNSPECIFIED);
			if (Header.has(RESTAPI::Protocol::CONTENTDISPOSITION)) {
				std::string Disposition;
				Poco::Net::NameValueCollection Parameters;
				Poco::Net::MessageHeader::splitParameters(
					Header[RESTAPI::Protocol::CONTENTDISPOSITION], Disposition, Parameters);
				Name_ = Parameters.get(RESTAPI::Protocol::NAME, RESTAPI::Protocol::UNNAMED);
			}
			Poco::CountingInputStream InputStream(Stream);
			Poco::StreamCopier::copyStream(InputStream, OutputStream_);
			Length_ = OutputStream_.str().size();
		}
		[[nodiscard]] uint64_t Length() const { return Length_; }
		[[nodiscard]] std::string &Name() { return Name_; }
		[[nodiscard]] std::string &ContentType() { return FileType_; }

	  private:
		uint64_t Length_ = 0;
		std::string FileType_;
		std::string Name_;
		std::string Id_;
		Poco::Logger &Logger_;
		std::stringstream &OutputStream_;

		inline Poco::Logger &Logger() { return Logger_; };
	};

	class FormRequestHandler : public Poco::Net::HTTPRequestHandler {
	  public:
		explicit FormRequestHandler(std::string UUID, Poco::Logger &L, const std::string &Type)
			: UUID_(std::move(UUID)), Logger_(L), Type_(Type) {}

		void handleRequest(Poco::Net::HTTPServerRequest &Request,
						   Poco::Net::HTTPServerResponse &Response) final {

			Utils::SetThreadName("FileUploader");
			const auto ContentType = Request.getContentType();
			const auto Tokens =
				Poco::StringTokenizer(ContentType, ";", Poco::StringTokenizer::TOK_TRIM);

			poco_debug(Logger(), fmt::format("{}: Preparing to upload a file.", UUID_));
			Poco::JSON::Object Answer;

			try {
				if (Poco::icompare(Tokens[0], "multipart/form-data") == 0 ||
					Poco::icompare(Tokens[0], "multipart/mixed") == 0) {

					const auto &BoundaryTokens =
						Poco::StringTokenizer(Tokens[1], "=", Poco::StringTokenizer::TOK_TRIM);

					if (BoundaryTokens[0] == "boundary") {
						const std::string &Boundary = BoundaryTokens[1];
						Poco::Net::MultipartReader Reader(Request.stream(), Boundary);
						bool Done = false;

						while (!Done) {
							Poco::Net::MessageHeader Hdr;
							Reader.nextPart(Hdr);

							const auto PartContentType = Hdr.get("Content-Type", "");
							if (PartContentType == "application/octet-stream") {
								std::stringstream FileContent;
								Poco::StreamCopier::copyStream(Reader.stream(), FileContent);
								Answer.set("filename", UUID_);
								Answer.set("error", 0);
								poco_debug(Logger(), fmt::format("{}: File uploaded.", UUID_));
								StorageService()->AttachFileDataToCommand(UUID_, FileContent,
																		  Type_);
								std::ostream &ResponseStream = Response.send();
								Poco::JSON::Stringifier::stringify(Answer, ResponseStream);
								return;
							} else {
								std::stringstream OO;
								Poco::StreamCopier::copyStream(Reader.stream(), OO);
							}

							if (!Reader.hasNextPart())
								Done = true;
						}
					}
				}
			} catch (const Poco::Exception &E) {
				Logger().log(E);
			} catch (...) {
				poco_debug(Logger(), "Exception while receiving uploaded file.");
			}

			poco_debug(Logger(), fmt::format("{}: Failed to upload a file.", UUID_));
			std::string Error{"File rejected"};
			StorageService()->CancelWaitFile(UUID_, Error);
			Answer.set("filename", UUID_);
			Answer.set("error", 13);
			Answer.set("errorText", "Attached file is too large");
			StorageService()->CancelWaitFile(UUID_, Error);
			std::ostream &ResponseStream = Response.send();
			Poco::JSON::Stringifier::stringify(Answer, ResponseStream);
		}

		inline Poco::Logger &Logger() { return Logger_; }

	  private:
		std::string UUID_;
		Poco::Logger &Logger_;
		std::string Type_;
	};

	Poco::Net::HTTPRequestHandler *FileUpLoaderRequestHandlerFactory::createRequestHandler(
		const Poco::Net::HTTPServerRequest &Request) {

		poco_debug(Logger(), fmt::format("REQUEST({}): {} {}",
										 Utils::FormatIPv6(Request.clientAddress().toString()),
										 Request.getMethod(), Request.getURI()));

		if (Request.getMethod() != Poco::Net::HTTPRequest::HTTP_POST ||
			Request.getURI().size() < (URI_BASE.size() + 36)) {
			poco_warning(Logger(),
						 fmt::format("ILLEGAL-REQUEST({}): {} {}. Dropped.",
									 Utils::FormatIPv6(Request.clientAddress().toString()),
									 Request.getMethod(), Request.getURI()));
			return nullptr;
		}

		//  The UUID should be after the /v1/upload/ part...
		auto UUIDLocation = Request.getURI().find_first_of(URI_BASE);

		if (UUIDLocation != std::string::npos) {
			auto UUID = Request.getURI().substr(UUIDLocation + URI_BASE.size());

			FileUploader::UploadId E;
			if (FileUploader()->Find(UUID, E)) {
				FileUploader()->RemoveRequest(UUID);
				return new FormRequestHandler(UUID, Logger(), E.Type);
			} else {
				poco_warning(Logger(), fmt::format("Unknown UUID={}", UUID));
			}
		}
		return nullptr;
	}

	bool FileUploader::Find(const std::string &UUID, UploadId &V) {
		std::lock_guard G(Mutex_);
		for (const auto &E : OutStandingUploads_) {
			if (E.UUID == UUID) {
				V = E;
				return true;
			}
		}
		return false;
	}

	void FileUploader::Stop() {
		poco_notice(Logger(), "Stopping...");
		for (const auto &svr : Servers_)
			svr->stopAll(true);
		Servers_.clear();
		poco_notice(Logger(), "Stopped...");
	}

} // namespace OpenWifi