#include "posprinter.h"

#include <exception>
#include <iostream>
#include <string>

PosPrinter::PosPrinter()
{
    int retValue;

    retValue = libusb_init(&contextPtr_);
    if (retValue < 0) {
        throw std::runtime_error("Init error");
    }

    libusb_device** devList;
    int devCount = libusb_get_device_list(contextPtr_, &devList);
    if (devCount <= 0) {
        libusb_exit(contextPtr_);
        throw std::runtime_error("Could not receive device list");
    }
    int numDevice = -1;
    for (int i = 0; i < devCount; ++i) {
        libusb_device_descriptor desc;
        libusb_get_device_descriptor(devList[i], &desc);
        for (const auto& supported : supportedPrinters_.models) {
            if (desc.idVendor == supported.first && desc.idProduct == supported.second) {
                numDevice = i;
                break;
            }
        }
    }

    if (numDevice < 0) {
        libusb_exit(contextPtr_);
        return;
    }

    retValue = libusb_open(devList[numDevice], &devicePtr_); // these are vendorID and productID
    if (retValue != 0) {
        libusb_free_device_list(devList, 1);
        libusb_exit(contextPtr_);
        throw std::runtime_error("Cannot open printer device");
    }

    if (libusb_kernel_driver_active(devicePtr_, 0) == 1) { // find out if kernel driver is attached
        std::cout << "Kernel driver active" << std::endl;
        if (libusb_detach_kernel_driver(devicePtr_, 0) == 0) // detach it
            std::cout << "Kernel driver detached!" << std::endl;
    }

    retValue = libusb_claim_interface(
        devicePtr_, 0); // claim interface 0 (the first) of device (mine had jsut 1)
    if (retValue < 0) {
        std::cout << "Cannot claim printer interface" << std::endl;
        throw std::runtime_error("Cannot claim printer interface");
    }

    libusb_free_device_list(devList, 1);
}

PosPrinter::~PosPrinter()
{
    int retValue;
    retValue = libusb_release_interface(devicePtr_, 0); // release the claimed interface
    if (retValue != 0) {
        std::cout << "Cannot release printer interface" << std::endl;
    } else {
        std::cout << "Printer interface released" << std::endl;
    }

    libusb_close(devicePtr_); // close the device we opened
    libusb_exit(contextPtr_); // close the session
}