#include "StrHelper.h"

#include "mission/utility/Timestamp.h"

#include <fstream>
#include <filesystem>

StrHelper::StrHelper(object_id_t objectId) : SystemObject(objectId){

}

StrHelper::~StrHelper() {
}

ReturnValue_t StrHelper::initialize() {
    sdcMan = SdCardManager::instance();
    if (sdcMan == nullptr) {
        sif::warning << "StrHelper::initialize: Invalid SD Card Manager" << std::endl;
        return RETURN_FAILED;
    }
    return RETURN_OK;
}

ReturnValue_t StrHelper::performOperation(uint8_t operationCode) {
    ReturnValue_t result = RETURN_OK;
    semaphore.acquire();
    while(true) {
        switch(internalState) {
        case InternalState::IDLE: {
            semaphore.acquire();
            break;
        }
        case InternalState::UPLOAD_IMAGE: {
            result = performImageUpload();
            if (result == RETURN_OK){
                triggerEvent(IMAGE_UPLOAD_SUCCESSFUL);
            }
            else {
                triggerEvent(IMAGE_UPLOAD_FAILED);
            }
            internalState = InternalState::IDLE;
            break;
        }
        case InternalState::DOWNLOAD_IMAGE: {
            result = performImageDownload();
            if (result == RETURN_OK){
                triggerEvent(IMAGE_DOWNLOAD_SUCCESSFUL);
            }
            else {
                triggerEvent(IMAGE_DOWNLOAD_FAILED);
            }
            internalState = InternalState::IDLE;
            break;
        }
        case InternalState::FLASH_WRITE: {
            result = performFlashWrite();
            if (result == RETURN_OK){
                triggerEvent(FLASH_WRITE_SUCCESSFUL);
            }
            else {
                triggerEvent(FLASH_WRITE_FAILED);
            }
            internalState = InternalState::IDLE;
            break;
        }
        default:
            sif::debug << "StrHelper::performOperation: Invalid state" << std::endl;
            break;
        }
    }
}

ReturnValue_t StrHelper::setComIF(DeviceCommunicationIF* communicationInterface_) {
    uartComIF = dynamic_cast<UartComIF*>(communicationInterface_);
    if (uartComIF == nullptr) {
        sif::warning << "StrHelper::initialize: Invalid uart com if" << std::endl;
        return RETURN_FAILED;
    }
    return RETURN_OK;
}

void StrHelper::setComCookie(CookieIF* comCookie_) {
    comCookie = comCookie_;
}

ReturnValue_t StrHelper::startImageUpload(std::string uploadImage_) {
    ReturnValue_t result = checkPath(uploadImage_);
    if (result != RETURN_OK) {
        return result;
    }
    uploadImage = uploadImage_;
    if(not std::filesystem::exists(uploadImage)) {
        return FILE_NOT_EXISTS;
    }
    internalState = InternalState::UPLOAD_IMAGE;
    semaphore.release();
    terminate = false;
    return RETURN_OK;
}

ReturnValue_t StrHelper::startImageDownload(std::string downloadPath_) {
    ReturnValue_t result = checkPath(downloadPath_);
    if (result != RETURN_OK) {
        return result;
    }
    if(not std::filesystem::exists(downloadPath_)) {
        return PATH_NOT_EXISTS;
    }
    downloadPath = downloadPath_;
    internalState = InternalState::DOWNLOAD_IMAGE;
    terminate = false;
    semaphore.release();
    return RETURN_OK;
}

void StrHelper::stopProcess() {
    terminate = true;
}

void StrHelper::setDownloadImageName(std::string image) {
    downloadImage = image;
}

ReturnValue_t StrHelper::startFlashWrite(std::string flashWriteFile_, uint8_t region,
        uint32_t flashWriteAddress) {
    ReturnValue_t result = checkPath(flashWriteFile_);
    if (result != RETURN_OK) {
        return result;
    }
    flashWriteFile = flashWriteFile_;
    if(not std::filesystem::exists(flashWriteFile)) {
        return FILE_NOT_EXISTS;
    }
    internalState = InternalState::FLASH_WRITE;
    semaphore.release();
    terminate = false;
    return RETURN_OK;
}

ReturnValue_t StrHelper::performImageDownload() {
    ReturnValue_t result;
    struct DownloadActionRequest downloadReq;
    uint32_t size = 0;
    uint32_t retries = 0;
    Timestamp timestamp;
    std::string image = downloadPath + "/" + timestamp.str() + downloadImage ;
    std::ofstream file(image, std::ios_base::app | std::ios_base::out);
    if(not std::filesystem::exists(image)) {
        return FILE_CREATION_FAILED;
    }
    downloadReq.position = 0;
    while(downloadReq.position < LAST_POSITION) {
        if (terminate) {
            return RETURN_OK;
        }
        arc_pack_download_action_req(&downloadReq, commandBuffer, &size);
        result = sendAndRead(size, downloadReq.position);
        if (result != RETURN_OK) {
            if (retries < CONFIG_MAX_DOWNLOAD_RETRIES) {
                uartComIF->flushUartRxBuffer(comCookie);
                retries++;
                continue;
            }
            file.close();
            return result;
        }
        result = checkReply();
        if (result != RETURN_OK) {
            if (retries < CONFIG_MAX_DOWNLOAD_RETRIES) {
                uartComIF->flushUartRxBuffer(comCookie);
                retries++;
                continue;
            }
            file.close();
            return result;
        }
        result = checkReplyPosition(downloadReq.position);
        if (result != RETURN_OK) {
            if (retries < CONFIG_MAX_DOWNLOAD_RETRIES) {
                uartComIF->flushUartRxBuffer(comCookie);
                retries++;
                continue;
            }
            file.close();
            return result;
        }
        file.write(reinterpret_cast<const char*>(datalinkLayer.getReply() + DATA_OFFSET),
                IMAGE_DATA_SIZE);
        downloadReq.position++;
        retries = 0;
    }
    file.close();
    return RETURN_OK;
}

ReturnValue_t StrHelper::performImageUpload() {
    ReturnValue_t result = RETURN_OK;
    uint32_t size = 0;
    uint32_t imageSize = 0;
    struct UploadActionRequest uploadReq;
    uploadReq.position = 0;
    std::memset(&uploadReq.data, 0, sizeof(uploadReq.data));
    if (not std::filesystem::exists(uploadImage)) {
        triggerEvent(STR_HELPER_FILE_NOT_EXISTS, static_cast<uint32_t>(internalState));
        internalState = InternalState::IDLE;
        return RETURN_FAILED;
    }
    std::ifstream file(uploadImage, std::ifstream::binary);
    // Set position of next character to end of file input stream
    file.seekg(0, file.end);
    // tellg returns position of character in input stream
    imageSize = file.tellg();
    while((uploadReq.position + 1) * SIZE_IMAGE_PART < imageSize) {
        if (terminate) {
            return RETURN_OK;
        }
        file.seekg(uploadReq.position * SIZE_IMAGE_PART, file.beg);
        file.read(reinterpret_cast<char*>(uploadReq.data), SIZE_IMAGE_PART);
        arc_pack_upload_action_req(&uploadReq, commandBuffer, &size);
        result = sendAndRead(size, uploadReq.position);
        if (result != RETURN_OK) {
            return RETURN_FAILED;
        }
        result = checkReply();
        if (result != RETURN_OK) {
            return result;
        }
        uploadReq.position++;
    }
    std::memset(uploadReq.data, 0, sizeof(uploadReq.data));
    uint32_t remainder = imageSize - uploadReq.position * SIZE_IMAGE_PART;
    file.seekg(uploadReq.position * SIZE_IMAGE_PART, file.beg);
    file.read(reinterpret_cast<char*>(uploadReq.data), remainder);
    file.close();
    uploadReq.position++;
    arc_pack_upload_action_req(&uploadReq, commandBuffer, &size);
    result = sendAndRead(size, uploadReq.position);
    if (result != RETURN_OK) {
        return RETURN_FAILED;
    }
    result = checkReply();
    if (result != RETURN_OK) {
        return result;
    }
    return RETURN_OK;
}

ReturnValue_t StrHelper::performFlashWrite() {
    ReturnValue_t result = RETURN_OK;
    uint32_t size = 0;
    uint32_t remainingBytes = 0;
    uint32_t fileSize = 0;
    struct WriteActionRequest req;
    if (not std::filesystem::exists(flashWriteFile)) {
        triggerEvent(STR_HELPER_FILE_NOT_EXISTS, static_cast<uint32_t>(internalState));
        internalState = InternalState::IDLE;
        return RETURN_FAILED;
    }
    std::ifstream file(flashWriteFile, std::ifstream::binary);
    file.seekg(0, file.end);
    fileSize = file.tellg();
    remainingBytes = fileSize;
    req.region = flashWriteRegion;
    req.address = flashWriteAddress;
    req.length = MAX_FLASH_DATA;
    while(remainingBytes >= MAX_FLASH_DATA) {
        if (terminate) {
            return RETURN_OK;
        }
        file.seekg(fileSize - remainingBytes, file.beg);
        file.read(reinterpret_cast<char*>(req.data), MAX_FLASH_DATA);
        arc_pack_write_action_req(&req, commandBuffer, &size);
        result = sendAndRead(size, req.address);
        if (result != RETURN_OK) {
            return RETURN_FAILED;
        }
        result = checkFlashWriteReply(req);
        if (result != RETURN_OK) {
            return result;
        }
        remainingBytes = remainingBytes - MAX_FLASH_DATA;
    }
    file.seekg(fileSize - remainingBytes, file.beg);
    file.read(reinterpret_cast<char*>(req.data), remainingBytes);
    file.close();
    arc_pack_write_action_req(&req, commandBuffer, &size);
    result = sendAndRead(size, req.address);
    if (result != RETURN_OK) {
        return RETURN_FAILED;
    }
    result = checkFlashWriteReply(req);
    if (result != RETURN_OK) {
        return result;
    }
    return RETURN_OK;
}

ReturnValue_t StrHelper::sendAndRead(size_t size, uint32_t parameter) {
    ReturnValue_t result = RETURN_OK;
    ReturnValue_t decResult = RETURN_OK;
    size_t receivedDataLen = 0;
    uint8_t *receivedData = nullptr;
    size_t bytesLeft = 0;
    uint32_t missedReplies = 0;
    datalinkLayer.encodeFrame(commandBuffer, size);
    result = uartComIF->sendMessage(comCookie, datalinkLayer.getEncodedFrame(),
        datalinkLayer.getEncodedLength());
    if (result != RETURN_OK) {
        sif::warning << "StrHelper::sendAndRead: Failed to send packet" << std::endl;
        triggerEvent(STR_HELPER_SENDING_PACKET_FAILED, result, parameter);
        return RETURN_FAILED;
    }
    decResult = ArcsecDatalinkLayer::DEC_IN_PROGRESS;
    while (decResult == ArcsecDatalinkLayer::DEC_IN_PROGRESS) {
        result = uartComIF->requestReceiveMessage(comCookie,
                StarTracker::MAX_FRAME_SIZE * 2 + 2);
        if (result != RETURN_OK) {
            sif::warning << "StrHelper::sendAndRead: Failed to request reply" << std::endl;
            triggerEvent(STR_HELPER_REQUESTING_MSG_FAILED, result, parameter);
            return RETURN_FAILED;
        }
        result = uartComIF->readReceivedMessage(comCookie, &receivedData, &receivedDataLen);
        if (result != RETURN_OK) {
            sif::warning << "StrHelper::sendAndRead: Failed to read received message" << std::endl;
            triggerEvent(STR_HELPER_READING_REPLY_FAILED, result, parameter);
            return RETURN_FAILED;
        }
        if (receivedDataLen == 0 && missedReplies < MAX_POLLS) {
            missedReplies++;
            continue;
        }
        else if ((receivedDataLen == 0) && (missedReplies >= MAX_POLLS)) {
            triggerEvent(STR_HELPER_NO_REPLY, parameter);
            return RETURN_FAILED;
        }
        else {
            missedReplies = 0;
        }
        decResult = datalinkLayer.decodeFrame(receivedData, receivedDataLen, &bytesLeft);
        if (bytesLeft != 0) {
            // This should never happen
            sif::warning << "StrHelper::sendAndRead: Bytes left after decoding" << std::endl;
            triggerEvent(STR_HELPER_COM_ERROR, result, parameter);
            return RETURN_FAILED;
        }
    }
    if (decResult != RETURN_OK) {
        triggerEvent(STR_HELPER_DEC_ERROR, decResult, parameter);
        return RETURN_FAILED;
    }
    return RETURN_OK;
}

ReturnValue_t StrHelper::checkReply() {
    uint8_t type = datalinkLayer.getReplyFrameType();
    if (type != TMTC_ACTIONREPLY) {
        sif::warning << "StrHelper::checkReply: Received reply with invalid type ID"
                << std::endl;
        triggerEvent(INVALID_TYPE_ID);
        return RETURN_FAILED;
    }
    uint8_t status = datalinkLayer.getStatusField();
    if (status != ArcsecDatalinkLayer::STATUS_OK) {
        triggerEvent(STATUS_ERROR);
        sif::warning << "StrHelper::checkReply: Status failure" << std::endl;
        return RETURN_FAILED;
    }
    return RETURN_OK;
}

ReturnValue_t StrHelper::checkReplyPosition(uint32_t expectedPosition) {
    uint32_t receivedPosition = 0;
    std::memcpy(&receivedPosition, datalinkLayer.getReply() + POS_OFFSET, sizeof(receivedPosition));
    if (receivedPosition != expectedPosition) {
        triggerEvent(POSITION_MISMATCH, receivedPosition);
        return RETURN_FAILED;
    }
    return RETURN_OK;
}

ReturnValue_t StrHelper::checkFlashWriteReply(struct WriteActionRequest& req) {
    ReturnValue_t result = RETURN_OK;
    const uint8_t* data = datalinkLayer.getReply();
    uint8_t region = *(data + REGION_OFFSET);
    uint32_t address;
    const uint8_t* addressData = data + ADDRESS_OFFSET;
    size_t size = sizeof(address);
    result = SerializeAdapter::deSerialize(&address, &addressData, &size,
                SerializeIF::Endianness::LITTLE);
    if (result != RETURN_OK) {
        sif::warning << "StrHelper::checkFlashWriteReply: Deserialization of address failed"
                << std::endl;
    }
    uint16_t length;
    size = sizeof(length);
    const uint8_t* lengthData = data + LENGTH_OFFSET;
    result = SerializeAdapter::deSerialize(&length, lengthData, &size,
                SerializeIF::Endianness::LITTLE);
    if (result != RETURN_OK) {
        sif::warning << "StrHelper::checkFlashWriteReply: Deserialization of length failed"
                << std::endl;
    }
    if (region != req.region) {
        return REGION_MISMATCH;
    }
    if (address != req.address) {
        return ADDRESS_MISMATCH;
    }
    if (region != req.length) {
        return LENGTH_MISMATCH;
    }
    return RETURN_OK;
}

ReturnValue_t StrHelper::checkPath(std::string name) {
    if (name.substr(0, sizeof(SdCardManager::SD_0_MOUNT_POINT))
            == std::string(SdCardManager::SD_0_MOUNT_POINT)) {
        if (!sdcMan->isSdCardMounted(sd::SLOT_0)) {
            sif::warning << "StrHelper::checkPath: SD card 0 not mounted" << std::endl;
            return SD_NOT_MOUNTED;
        }
    } else if (name.substr(0, sizeof(SdCardManager::SD_1_MOUNT_POINT))
            == std::string(SdCardManager::SD_1_MOUNT_POINT)) {
        if (!sdcMan->isSdCardMounted(sd::SLOT_0)) {
            sif::warning << "StrHelper::checkPath: SD card 1 not mounted" << std::endl;
            return SD_NOT_MOUNTED;
        }
    }
    return RETURN_OK;
}