#include "hostSelector_switch.hpp"

#include <error.h>

#include <phosphor-logging/lg2.hpp>

// add the button iface class to registry
static ButtonIFRegister<HostSelector> buttonRegister;

size_t HostSelector::getMappedHSConfig(size_t hsPosition)
{
    size_t adjustedPosition = INVALID_INDEX; // set bmc as default value
    std::string hsPosStr;
    hsPosStr = std::to_string(hsPosition);

    if (hsPosMap.find(hsPosStr) != hsPosMap.end())
    {
        adjustedPosition = hsPosMap[hsPosStr];
    }
    else
    {
        lg2::debug("getMappedHSConfig : {TYPE}: no valid value in map.", "TYPE",
                   getFormFactorType());
    }
    return adjustedPosition;
}

size_t HostSelector::getGpioIndex(int fd)
{
    for (size_t index = 0; index < gpioLineCount; index++)
    {
        if (config.gpios[index].fd == fd)
        {
            return index;
        }
    }
    return INVALID_INDEX;
}

char HostSelector::getValueFromFd(int fd)
{
    char buf;
    auto result = ::lseek(fd, 0, SEEK_SET);

    if (result < 0)
    {
        throw sdbusplus::xyz::openbmc_project::Chassis::Common::Error::
            IOError();
    }

    result = ::read(fd, &buf, sizeof(buf));
    if (result < 0)
    {
        throw sdbusplus::xyz::openbmc_project::Chassis::Common::Error::
            IOError();
    }
    return buf;
}

void HostSelector::setInitialHostSelectorValue()
{
    size_t hsPosMapped = 0;

    try
    {
        if (config.type == ConfigType::gpio)
        {
            for (size_t index = 0; index < gpioLineCount; index++)
            {
                GpioState gpioState =
                    (getValueFromFd(config.gpios[index].fd) == '0')
                        ? (GpioState::deassert)
                        : (GpioState::assert);
                setHostSelectorValue(config.gpios[index].fd, gpioState);
            }
            hsPosMapped = getMappedHSConfig(hostSelectorPosition);
        }
        else if (config.type == ConfigType::cpld)
        {
            hsPosMapped = getValueFromFd(config.cpld.cpldMappedFd) - '0';
        }
    }
    catch (const std::exception& e)
    {
        lg2::error("{TYPE}: exception while reading fd : {ERROR}", "TYPE",
                   getFormFactorType(), "ERROR", e.what());
    }

    if (hsPosMapped != INVALID_INDEX)
    {
        position(hsPosMapped, true);
    }
}

void HostSelector::setHostSelectorValue(int fd, GpioState state)
{
    size_t pos = getGpioIndex(fd);

    if (pos == INVALID_INDEX)
    {
        return;
    }
    auto set_bit = [](size_t& val, size_t n) { val |= 0xff & (1 << n); };

    auto clr_bit = [](size_t& val, size_t n) { val &= ~(0xff & (1 << n)); };

    auto bit_op = (state == GpioState::deassert) ? set_bit : clr_bit;

    bit_op(hostSelectorPosition, pos);
    return;
}
/**
 * @brief This method is called from sd-event provided callback function
 * callbackHandler if platform specific event handling is needed then a
 * derived class instance with its specific event handling logic along with
 * init() function can be created to override the default event handling
 */

void HostSelector::handleEvent(sd_event_source* /* es */, int fd,
                               uint32_t /* revents */)
{
    char buf = '0';
    try
    {
        buf = getValueFromFd(fd);
    }
    catch (const std::exception& e)
    {
        lg2::error("{TYPE}: exception while reading fd : {ERROR}", "TYPE",
                   getFormFactorType(), "ERROR", e.what());
        return;
    }

    size_t hsPosMapped = 0;
    if (config.type == ConfigType::gpio)
    {
        // read the gpio state for the io event received
        GpioState gpioState =
            (buf == '0') ? (GpioState::deassert) : (GpioState::assert);

        setHostSelectorValue(fd, gpioState);
        hsPosMapped = getMappedHSConfig(hostSelectorPosition);
    }
    else if (config.type == ConfigType::cpld)
    {
        hsPosMapped = buf - '0';
    }

    if (hsPosMapped != INVALID_INDEX)
    {
        position(hsPosMapped);
    }
}