/*
 * Copyright (C) 2011-2012 Doug Brown
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * 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 General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
 *
 */

#include "programmer.h"
#include <QDebug>
#include <QWaitCondition>
#include <QMutex>

typedef enum ProgrammerCommandState
{
    WaitingForNextCommand = 0,

    WriteSIMMWaitingEraseReply,
    WriteSIMMWaitingWriteReply,
    WriteSIMMWaitingFinishReply,
    WriteSIMMWaitingWriteMoreReply,

    ElectricalTestWaitingStartReply,
    ElectricalTestWaitingNextStatus,
    ElectricalTestWaitingFirstFail,
    ElectricalTestWaitingSecondFail,

    ReadSIMMWaitingStartReply,
    ReadSIMMWaitingLengthReply,
    ReadSIMMWaitingData,
    ReadSIMMWaitingStatusReply,

    BootloaderStateAwaitingOKReply,
    BootloaderStateAwaitingReply,
    BootloaderStateAwaitingOKReplyToBootloader,
    BootloaderStateAwaitingReplyToBootloader,
    BootloaderStateAwaitingUnplug,
    BootloaderStateAwaitingPlug,
    BootloaderStateAwaitingUnplugToBootloader,
    BootloaderStateAwaitingPlugToBootloader,

    IdentificationAwaitingOKReply,
    IdentificationWaitingData,
    IdentificationAwaitingDoneReply,

    BootloaderEraseProgramAwaitingStartOKReply,
    BootloaderEraseProgramWaitingFinishReply,
    BootloaderEraseProgramWaitingWriteMoreReply,
    BootloaderEraseProgramWaitingWriteReply
} ProgrammerCommandState;

typedef enum ProgrammerBoardFoundState
{
    ProgrammerBoardNotFound,
    ProgrammerBoardFound
} ProgrammerBoardFoundState;

typedef enum ProgrammerCommand
{
    EnterWaitingMode = 0,
    DoElectricalTest,
    IdentifyChips,
    ReadByte,
    ReadChips,
    EraseChips,
    WriteChips,
    GetBootloaderState,
    EnterBootloader,
    EnterProgrammer,
    BootloaderEraseAndWriteProgram
} ProgrammerCommand;

typedef enum ProgrammerReply
{
    CommandReplyOK,
    CommandReplyError,
    CommandReplyInvalid
} ProgrammerReply;

typedef enum ComputerReadReply
{
    ComputerReadOK,
    ComputerReadCancel
} ComputerReadReply;

typedef enum ProgrammerReadReply
{
    ProgrammerReadOK,
    ProgrammerReadError,
    ProgrammerReadMoreData,
    ProgrammerReadFinished,
    ProgrammerReadConfirmCancel
} ProgrammerReadReply;

typedef enum ComputerWriteReply
{
    ComputerWriteMore,
    ComputerWriteFinish,
    ComputerWriteCancel
} ComputerWriteReply;

typedef enum ProgrammerWriteReply
{
    ProgrammerWriteOK,
    ProgrammerWriteError,
    ProgrammerWriteConfirmCancel
} ProgrammerWriteReply;

typedef enum ProgrammerIdentifyReply
{
    ProgrammerIdentifyDone
} ProgrammerIdentifyReply;

typedef enum ProgrammerElectricalTestReply
{
    ProgrammerElectricalTestFail,
    ProgrammerElectricalTestDone
} ProgrammerElectricalTestReply;

typedef enum BootloaderStateReply
{
    BootloaderStateInBootloader,
    BootloaderStateInProgrammer
} BootloaderStateReply;

typedef enum ProgrammerBootloaderEraseWriteReply
{
    BootloaderWriteOK,
    BootloaderWriteError,
    BootloaderWriteConfirmCancel
} ProgrammerBootloaderEraseWriteReply;

typedef enum ComputerBootloaderEraseWriteRequest
{
    ComputerBootloaderWriteMore = 0,
    ComputerBootloaderFinish,
    ComputerBootloaderCancel
} ComputerBootloaderEraseWriteRequest;

#define PROGRAMMER_USB_VENDOR_ID            0x16D0
#define PROGRAMMER_USB_DEVICE_ID            0x06AA


#define WRITE_CHUNK_SIZE    1024
#define READ_CHUNK_SIZE     1024
#define FIRMWARE_CHUNK_SIZE 1024

static ProgrammerCommandState curState = WaitingForNextCommand;

// After identifying that we're in the main program, what will be the command
// we will send and the state we will be waiting in?
static ProgrammerCommandState nextState = WaitingForNextCommand;
static uint8_t nextSendByte = 0;

static ProgrammerBoardFoundState foundState = ProgrammerBoardNotFound;
static QString programmerBoardPortName;

Programmer::Programmer(QObject *parent) :
    QObject(parent)
{
    serialPort = new QextSerialPort(QextSerialPort::EventDriven);
    connect(serialPort, SIGNAL(readyRead()), SLOT(dataReady()));
}

Programmer::~Programmer()
{
    closePort();
    delete serialPort;
}

void Programmer::readSIMM(QIODevice *device)
{
    //readFile = new QFile(filename);
    //readFile->open(QFile::WriteOnly);
    //lenRead = 0;
    //lenRemaining = _simmCapacity;

    readDevice = device;
    lenRead = 0;
    lenRemaining = _simmCapacity;

    startProgrammerCommand(ReadChips, ReadSIMMWaitingStartReply);
}

void Programmer::writeToSIMM(QIODevice *device)
{
    /*writeFile = new QFile(filename);
    if (!writeFile->open(QFile::ReadOnly))
    {
        curState = WaitingForNextCommand;
        emit writeStatusChanged(WriteError);
        return;
    }
    if (writeFile->size() > _simmCapacity)
    {
        curState = WaitingForNextCommand;
        emit writeStatusChanged(WriteFileTooBig);
        return;
    }
    else
    {
        lenWritten = 0;
        writeLenRemaining = writeFile->size();

        startProgrammerCommand(EraseChips, WriteSIMMWaitingEraseReply);
    }*/

    writeDevice = device;
    if (writeDevice->size() > _simmCapacity)
    {
        curState = WaitingForNextCommand;
        emit writeStatusChanged(WriteFileTooBig);
        return;
    }
    else
    {
        lenWritten = 0;
        writeLenRemaining = writeDevice->size();

        startProgrammerCommand(EraseChips, WriteSIMMWaitingEraseReply);
    }
}

void Programmer::sendByte(uint8_t b)
{
    serialPort->write((const char *)&b, 1);
}

uint8_t Programmer::readByte()
{
    uint8_t returnVal;
    serialPort->read((char *)&returnVal, 1);
    // TODO: Error checking if read fails?
    return returnVal;
}

void Programmer::dataReady()
{
    while (!serialPort->atEnd())
    {
        handleChar(readByte());
    }
}

void Programmer::handleChar(uint8_t c)
{
    switch (curState)
    {
    case WaitingForNextCommand:
        // Not expecting anything. Ignore it.
        break;
    case WriteSIMMWaitingEraseReply:
    {
        switch (c)
        {
        case CommandReplyOK:
            sendByte(WriteChips);
            curState = WriteSIMMWaitingWriteReply;
            qDebug() << "Chips erased. Now asking to start writing...";
            emit writeStatusChanged(WriteEraseComplete);
            emit writeTotalLengthChanged(writeLenRemaining);
            emit writeCompletionLengthChanged(lenWritten);
            break;
        case CommandReplyError:
            qDebug() << "Error erasing chips.";
            curState = WaitingForNextCommand;
            closePort();
            emit writeStatusChanged(WriteEraseFailed);
            break;
        }
        break;
    }
    case WriteSIMMWaitingWriteReply:
        switch (c)
        {
        case CommandReplyOK:
            // We're in write SIMM mode. Now ask to start writing
            if (writeLenRemaining > 0)
            {
                sendByte(ComputerWriteMore);
                curState = WriteSIMMWaitingWriteMoreReply;
                qDebug() << "Write more..." << writeLenRemaining << "remaining.";
            }
            else
            {
                sendByte(ComputerWriteFinish);
                curState = WriteSIMMWaitingFinishReply;
                qDebug() << "Finished writing. Sending write finish command...";
            }
            break;
        case CommandReplyError:
            qDebug() << "Error entering write mode.";
            curState = WaitingForNextCommand;
            closePort();
            emit writeStatusChanged(WriteError);
            break;
        }

        break;
    case WriteSIMMWaitingWriteMoreReply:
    {
        switch (c)
        {
        case ProgrammerWriteOK:
        {
            qDebug() << "Programmer replied OK to send 1024 bytes of data! Sending...";
            // Write the next chunk of data to the SIMM...

            int chunkSize = WRITE_CHUNK_SIZE;
            if (writeLenRemaining < WRITE_CHUNK_SIZE)
            {
                chunkSize = writeLenRemaining;
            }

            // Read the chunk from the file!
            QByteArray thisChunk = writeDevice->read(chunkSize);

            // If it isn't a WRITE_CHUNK_SIZE chunk, pad the rest of it with 0xFFs (unprogrammed bytes)
            // so the total chunk size is WRITE_CHUNK_SIZE, since that's what the programmer board expects.
            for (int x = writeLenRemaining; x < WRITE_CHUNK_SIZE; x++)
            {
                thisChunk.append(0xFF);
            }

            // Write the chunk out (it's asynchronous so will return immediately)
            serialPort->write(thisChunk);

            // OK, now we're waiting to hear back from the programmer on the result
            qDebug() << "Waiting for status reply...";
            curState = WriteSIMMWaitingWriteReply;
            writeLenRemaining -= chunkSize;
            lenWritten += chunkSize;
            emit writeCompletionLengthChanged(lenWritten);
            break;
        }
        case ProgrammerWriteError:
        default:
            qDebug() << "Error writing to chips.";
            curState = WaitingForNextCommand;
            closePort();
            emit writeStatusChanged(WriteError);
            break;
        }
        break;
    }
    case WriteSIMMWaitingFinishReply:
        switch (c)
        {
        case ProgrammerWriteOK:
            curState = WaitingForNextCommand;
            qDebug() << "Write success at end";
            closePort();
            emit writeStatusChanged(WriteComplete);
            break;
        case ProgrammerWriteError:
        default:
            qDebug() << "Write failure at end";
            curState = WaitingForNextCommand;
            closePort();
            emit writeStatusChanged(WriteError);
            break;
        }

        break;

    // ELECTRICAL TEST STATE HANDLERS

    case ElectricalTestWaitingStartReply:
        switch (c)
        {
        case CommandReplyOK:
            curState = ElectricalTestWaitingNextStatus;
            emit electricalTestStatusChanged(ElectricalTestStarted);
            electricalTestErrorCounter = 0;
            break;
        case CommandReplyError:
        case CommandReplyInvalid:
        default:
            curState = WaitingForNextCommand;
            closePort();
            emit electricalTestStatusChanged(ElectricalTestCouldntStart);
        }
        break;
    case ElectricalTestWaitingNextStatus:
        switch (c)
        {
        case ProgrammerElectricalTestDone:
            curState = WaitingForNextCommand;
            closePort();
            if (electricalTestErrorCounter > 0)
            {
                emit electricalTestStatusChanged(ElectricalTestFailed);
            }
            else
            {
                emit electricalTestStatusChanged(ElectricalTestPassed);
            }
            break;
        case ProgrammerElectricalTestFail:
            electricalTestErrorCounter++;
            curState = ElectricalTestWaitingFirstFail;
            break;
        }
        break;
    case ElectricalTestWaitingFirstFail:
        electricalTestFirstErrorLoc = c;
        curState = ElectricalTestWaitingSecondFail;
        break;
    case ElectricalTestWaitingSecondFail:
        emit electricalTestFailLocation(electricalTestFirstErrorLoc, c);
        curState = ElectricalTestWaitingNextStatus;
        break;

    // READ SIMM STATE HANDLERS
    case ReadSIMMWaitingStartReply:
        switch (c)
        {
        case CommandReplyOK:

            emit readStatusChanged(ReadStarting);
            curState = ReadSIMMWaitingLengthReply;

            // Send the length requesting to be read
            sendByte((lenRemaining >> 0)  & 0xFF);
            sendByte((lenRemaining >> 8)  & 0xFF);
            sendByte((lenRemaining >> 16) & 0xFF);
            sendByte((lenRemaining >> 24) & 0xFF);

            // Now wait for the go-ahead from the programmer's side
            break;
        case CommandReplyError:
        case CommandReplyInvalid:
        default:
            curState = WaitingForNextCommand;
            emit readStatusChanged(ReadError);
            break;
        }
        break;

    case ReadSIMMWaitingLengthReply:
        switch (c)
        {
        case ProgrammerReadOK:
            curState = ReadSIMMWaitingData;
            emit readTotalLengthChanged(_simmCapacity);
            emit readCompletionLengthChanged(0);
            readChunkLenRemaining = READ_CHUNK_SIZE;
            break;
        case ProgrammerReadError:
        default:
            curState = WaitingForNextCommand;
            closePort();
            emit readStatusChanged(ReadError);
            break;
        }
        break;
    case ReadSIMMWaitingData:
        readDevice->write((const char *)&c, 1);
        lenRead++;
        if (--readChunkLenRemaining == 0)
        {
            emit readCompletionLengthChanged(lenRead);
            qDebug() << "Received a chunk of data";
            sendByte(ComputerReadOK);
            curState = ReadSIMMWaitingStatusReply;
        }
        break;
    case ReadSIMMWaitingStatusReply:
        switch (c)
        {
        case ProgrammerReadFinished:
            curState = WaitingForNextCommand;
            closePort();
            emit readStatusChanged(ReadComplete);
            break;
        case ProgrammerReadConfirmCancel:
            curState = WaitingForNextCommand;
            closePort();
            emit readStatusChanged(ReadCancelled);
            break;
        case ProgrammerReadMoreData:
            curState = ReadSIMMWaitingData;
            readChunkLenRemaining = READ_CHUNK_SIZE;
            break;
        }

        break;

    // BOOTLOADER STATE HANDLERS
    case BootloaderStateAwaitingOKReply:
        if (c == CommandReplyOK)
        {
            // Good to go, now we're waiting for the "in programmer" or "in bootloader" reply.
            curState = BootloaderStateAwaitingReply;
        }
        else
        {
            curState = WaitingForNextCommand;
            qDebug() << "Unable to enter programmer mode";
            // TODO: Error out somehow
        }
        break;
    case BootloaderStateAwaitingReply:
        switch (c)
        {
        case BootloaderStateInBootloader:
            // Oops! We're in the bootloader. Better change over to the programmer.
            // TODO: Send "enter programmer" command.
            //       Close serial port.
            //       Wait for serial port to reappear (or just wait a fixed time?)
            //       Open serial port.
            //       Ensure we're in the programmer?
            //       Then do the command correctly
            qDebug() << "We're in the bootloader, so sending an \"enter programmer\" request.";
            emit startStatusChanged(ProgrammerInitializing);
            sendByte(EnterProgrammer);
            closePort();

            // Now wait for it to reconnect
            curState = BootloaderStateAwaitingUnplug;
            break;
        case BootloaderStateInProgrammer:
            // Good to go...
            // So change to the next state and send out the next command
            // to begin whatever sequence of events we expected.
            qDebug() << "Already in programmer. Good! Do the command now...";
            emit startStatusChanged(ProgrammerInitialized);
            curState = nextState;
            sendByte(nextSendByte);
            // Special case: Send out notification we are starting an erase command.
            // I don't have any hooks into the process between now and the erase reply.
            if (nextSendByte == EraseChips)
            {
                emit writeStatusChanged(WriteErasing);
            }
            break;
            // TODO: Otherwise, raise an error?
        }
        break;

    case BootloaderStateAwaitingOKReplyToBootloader:
        if (c == CommandReplyOK)
        {
            // Good to go, now we're waiting for the "in programmer" or "in bootloader" reply.
            curState = BootloaderStateAwaitingReplyToBootloader;
        }
        else
        {
            curState = WaitingForNextCommand;
            qDebug() << "Unable to enter bootloader mode";
            // TODO: Error out somehow
        }
        break;
    case BootloaderStateAwaitingReplyToBootloader:
        switch (c)
        {
        case BootloaderStateInProgrammer:
            // Oops! We're in the programmer. Better change over to the bootloader.
            // TODO: Send "enter bootloader" command.
            //       Close serial port.
            //       Wait for serial port to reappear (or just wait a fixed time?)
            //       Open serial port.
            //       Ensure we're in the bootloader?
            //       Then do the command correctly
            qDebug() << "We're in the programmer, so sending an \"enter bootloader\" request.";
            emit startStatusChanged(ProgrammerInitializing);
            sendByte(EnterBootloader);
            closePort();

            // Now wait for it to reconnect
            curState = BootloaderStateAwaitingUnplugToBootloader;
            break;
        case BootloaderStateInBootloader:
            // Good to go...
            // So change to the next state and send out the next command
            // to begin whatever sequence of events we expected.
            qDebug() << "Already in bootloader. Good! Do the command now...";
            emit startStatusChanged(ProgrammerInitialized);
            curState = nextState;
            sendByte(nextSendByte);
            break;
            // TODO: Otherwise, raise an error?
        }
        break;

    // IDENTIFICATION STATE HANDLERS
    case IdentificationAwaitingOKReply:
        if (c == CommandReplyOK)
        {
            // Good to go, now waiting for identification data
            emit identificationStatusChanged(IdentificationStarting);
            curState = IdentificationWaitingData;
            identificationCounter = 0;
        }
        else
        {
            emit identificationStatusChanged(IdentificationError);
            curState = WaitingForNextCommand;
        }
        break;
    case IdentificationWaitingData:
        if (identificationCounter & 1) // device ID?
        {
            chipDeviceIDs[identificationCounter/2] = c;
        }
        else // manufacturer ID?
        {
            chipManufacturerIDs[identificationCounter/2] = c;
        }

        // All done?
        if (++identificationCounter >= 8)
        {
            curState = IdentificationAwaitingDoneReply;
        }
        break;
    case IdentificationAwaitingDoneReply:
        curState = WaitingForNextCommand;
        closePort();
        if (c == ProgrammerIdentifyDone)
        {
            emit identificationStatusChanged(IdentificationComplete);
        }
        else
        {
            emit identificationStatusChanged(IdentificationError);
        }
        break;

    // WRITE BOOTLOADER PROGRAM STATE HANDLERS
    case BootloaderEraseProgramAwaitingStartOKReply:
        if (c == CommandReplyOK)
        {
            emit firmwareFlashStatusChanged(FirmwareFlashStarting);
            sendByte(ComputerBootloaderWriteMore);
            curState = BootloaderEraseProgramWaitingWriteMoreReply;
        }
        else
        {
            curState = WaitingForNextCommand;
            closePort();
            firmwareFile->close();
            emit firmwareFlashStatusChanged(FirmwareFlashError);
        }
        break;
    case BootloaderEraseProgramWaitingFinishReply:
        if (c == BootloaderWriteOK)
        {
            curState = WaitingForNextCommand;
            closePort();
            firmwareFile->close();
            emit firmwareFlashStatusChanged(FirmwareFlashComplete);
        }
        else
        {
            curState = WaitingForNextCommand;
            closePort();
            firmwareFile->close();
            emit firmwareFlashStatusChanged(FirmwareFlashError);
        }
        break;
    case BootloaderEraseProgramWaitingWriteMoreReply:
        if (c == BootloaderWriteOK)
        {
            // Send the next chunk of data
            qDebug() << "Bootloader replied OK to send 1024 bytes of data! Sending...";
            int chunkSize = FIRMWARE_CHUNK_SIZE;
            if (firmwareLenRemaining < FIRMWARE_CHUNK_SIZE)
            {
                chunkSize = firmwareLenRemaining;
            }

            // Read the chunk from the file!
            QByteArray thisChunk = firmwareFile->read(chunkSize);

            // If it isn't FIRMWARE_CHUNK_SIZE, pad the rest with 0xFF
            // (unprogrammed bytes)
            for (int x = firmwareLenRemaining; x < FIRMWARE_CHUNK_SIZE; x++)
            {
                thisChunk.append(0xFF);
            }

            // Write the chunk out (it's asynchronous so will return immediately)
            serialPort->write(thisChunk);

            // OK, now we're waiting to hear back from the programmer on the result
            qDebug() << "Waiting for status reply...";
            curState = BootloaderEraseProgramWaitingWriteReply;
            firmwareLenRemaining -= chunkSize;
            firmwareLenWritten += chunkSize;
            emit firmwareFlashCompletionLengthChanged(firmwareLenWritten);
        }
        else
        {
            curState = WaitingForNextCommand;
            closePort();
            firmwareFile->close();
            emit firmwareFlashStatusChanged(FirmwareFlashError);
        }
        break;
    case BootloaderEraseProgramWaitingWriteReply:
        if (c == CommandReplyOK)
        {
            // Either ask to send the next chunk, or send a "finish" response
            if (firmwareLenRemaining > 0)
            {
                sendByte(ComputerBootloaderWriteMore);
                curState = BootloaderEraseProgramWaitingWriteMoreReply;
            }
            else
            {
                sendByte(ComputerBootloaderFinish);
                curState = BootloaderEraseProgramWaitingFinishReply;
            }
        }
        else
        {
            curState = WaitingForNextCommand;
            closePort();
            firmwareFile->close();
            emit firmwareFlashStatusChanged(FirmwareFlashError);
        }
        break;

    // UNUSED STATE HANDLERS (They are handled elsewhere)
    case BootloaderStateAwaitingPlug:
    case BootloaderStateAwaitingUnplug:
    case BootloaderStateAwaitingPlugToBootloader:
    case BootloaderStateAwaitingUnplugToBootloader:
        break;
    }
}

void Programmer::runElectricalTest()
{
    startProgrammerCommand(DoElectricalTest, ElectricalTestWaitingStartReply);
}

QString Programmer::electricalTestPinName(uint8_t index)
{
    if (index <= LAST_ADDRESS_LINE_FAIL_INDEX)
    {
        return QString().sprintf("A%d", index - FIRST_ADDRESS_LINE_FAIL_INDEX);
    }
    else if (index <= LAST_DATA_LINE_FAIL_INDEX)
    {
        // The byte ordering is backwards to the labeling, so I have to fix that.
        // Reverse the byte ordering so we have the correct number in terms of how
        // D0 to D31 are labeled...
        index = index - FIRST_DATA_LINE_FAIL_INDEX;
        if (index < 8)
        {
            index = index + 24;
        }
        else if (index < 16)
        {
            index = index + 8;
        }
        else if (index < 24)
        {
            index = index - 8;
        }
        else
        {
            index = index - 24;
        }
        return QString().sprintf("D%d", index);
    }
    else if (index == CS_FAIL_INDEX)
    {
        return "CS";
    }
    else if (index == OE_FAIL_INDEX)
    {
        return "OE";
    }
    else if (index == WE_FAIL_INDEX)
    {
        return "WE";
    }
    else if (index == GROUND_FAIL_INDEX)
    {
        return "GND";
    }
    else
    {
        return "?";
    }
}

void Programmer::identifySIMMChips()
{
    startProgrammerCommand(IdentifyChips, IdentificationAwaitingOKReply);
}

void Programmer::getChipIdentity(int chipIndex, uint8_t *manufacturer, uint8_t *device)
{
    if ((chipIndex >= 0) && (chipIndex < 4))
    {
        *manufacturer = chipManufacturerIDs[chipIndex];
        *device = chipDeviceIDs[chipIndex];
    }
    else
    {
        *manufacturer = 0;
        *device = 0;
    }
}

void Programmer::flashFirmware(QString filename)
{
    firmwareFile = new QFile(filename);
    if (!firmwareFile->open(QFile::ReadOnly))
    {
        curState = WaitingForNextCommand;
        emit firmwareFlashStatusChanged(FirmwareFlashError);
        return;
    }

    firmwareLenWritten = 0;
    firmwareLenRemaining = firmwareFile->size();
    emit firmwareFlashTotalLengthChanged(firmwareLenRemaining);
    emit firmwareFlashCompletionLengthChanged(firmwareLenWritten);

    startBootloaderCommand(BootloaderEraseAndWriteProgram, BootloaderEraseProgramAwaitingStartOKReply);
}

// Begins a command by opening the serial port, making sure we're in the PROGRAMMER
// rather than the bootloader, then sending a command and setting a new command state.
// TODO: When it fails, this needs to carry errors over somehow.
// newState is really just a ProgrammerCommandState but in order to keep
// ProgrammerCommandState private, I did it this way.
void Programmer::startProgrammerCommand(uint8_t commandByte, uint32_t newState)
{
    nextState = (ProgrammerCommandState)newState;
    nextSendByte = commandByte;

    curState = BootloaderStateAwaitingOKReply;
    openPort();
    sendByte(GetBootloaderState);
}

// Begins a command by opening the serial port, making sure we're in the BOOTLOADER
// rather than the programmer, then sending a command and setting a new command state.
// TODO: When it fails, this needs to carry errors over somehow.
// newState is really just a ProgrammerCommandState but in order to keep
// ProgrammerCommandState private, I did it this way.
void Programmer::startBootloaderCommand(uint8_t commandByte, uint32_t newState)
{
    nextState = (ProgrammerCommandState)newState;
    nextSendByte = commandByte;

    curState = BootloaderStateAwaitingOKReplyToBootloader;
    openPort();
    sendByte(GetBootloaderState);
}

#include <QTimer>
void Programmer::portDiscovered(const QextPortInfo &info)
{
    if ((foundState == ProgrammerBoardNotFound) &&
        (info.vendorID == PROGRAMMER_USB_VENDOR_ID) &&
        (info.productID == PROGRAMMER_USB_DEVICE_ID) &&
        (info.portName != ""))
    {
        // Note: I check that portName != "" because QextSerialEnumerator seems to give me
        // 2 notifications that match the vendor ID -- one is the real deal, and the other
        // has a blank port name. If I match on the blank port name one, it breaks.

#ifdef Q_WS_WIN
        programmerBoardPortName = "\\\\.\\" + info.portName;
#else
        programmerBoardPortName = info.portName;
#endif
        foundState = ProgrammerBoardFound;

        // I create a temporary timer here because opening it immediately seems to crash
        // Mac OS X in my limited testing. Don't worry about a memory leak -- the
        // portDiscovered_internal() slot will delete the newly-allocated QTimer.
        QTimer *t = new QTimer();
        connect(t, SIGNAL(timeout()), SLOT(portDiscovered_internal()));
        t->setInterval(50);
        t->setSingleShot(true);
        t->start();
    }
}

void Programmer::portDiscovered_internal()
{
    // Delete the QTimer that sent us this signal. Ugly, but it works...
    sender()->deleteLater();

    closePort();
    serialPort->setPortName(programmerBoardPortName);

    // Don't show the "control" screen if we intentionally
    // reconnected the USB port because we are changing from bootloader
    // to programmer mode or vice-versa.
    if (curState == BootloaderStateAwaitingPlug)
    {
        openPort();
        curState = nextState;
        sendByte(nextSendByte);
        // Special case: Send out notification we are starting an erase command.
        // I don't have any hooks into the process between now and the erase reply.
        if (nextSendByte == EraseChips)
        {
            emit writeStatusChanged(WriteErasing);
        }
    }
    else if (curState == BootloaderStateAwaitingPlugToBootloader)
    {
        openPort();
        curState = nextState;
        sendByte(nextSendByte);
    }
    else
    {
        emit programmerBoardConnected();
    }
}

void Programmer::portRemoved(const QextPortInfo &info)
{
    if ((info.vendorID == PROGRAMMER_USB_VENDOR_ID) &&
        (info.productID == PROGRAMMER_USB_DEVICE_ID) &&
        (foundState == ProgrammerBoardFound))
    {       
        programmerBoardPortName = "";
        foundState = ProgrammerBoardNotFound;

        // Don't show the "no programmer connected" screen if we intentionally
        // disconnected the USB port because we are changing from bootloader
        // to programmer mode or vice-versa.
        if (curState == BootloaderStateAwaitingUnplug)
        {
            curState = BootloaderStateAwaitingPlug;
        }
        else if (curState == BootloaderStateAwaitingUnplugToBootloader)
        {
            curState = BootloaderStateAwaitingPlugToBootloader;
        }
        else
        {
            closePort();

            if (curState != WaitingForNextCommand)
            {
                // This means they unplugged while we were in the middle
                // of an operation. Reset state, and let them know.
                curState = WaitingForNextCommand;
                emit programmerBoardDisconnectedDuringOperation();
            }
            else
            {
                emit programmerBoardDisconnected();
            }
        }
    }
}

void Programmer::startCheckingPorts()
{
    QextSerialEnumerator *p = new QextSerialEnumerator();
    connect(p, SIGNAL(deviceDiscovered(QextPortInfo)), SLOT(portDiscovered(QextPortInfo)));
    connect(p, SIGNAL(deviceRemoved(QextPortInfo)), SLOT(portRemoved(QextPortInfo)));
    p->setUpNotifications();
}

void Programmer::openPort()
{
    serialPort->open(QextSerialPort::ReadWrite);
}

void Programmer::closePort()
{
    serialPort->close();
}

void Programmer::setSIMMCapacity(uint32_t bytes)
{
    _simmCapacity = bytes;
}

uint32_t Programmer::SIMMCapacity()
{
    return _simmCapacity;
}