import sh
import unittest
import os.path


class Qusbdual(unittest.TestCase):
    params = None
    __resultlist = None  # resultlist is a python list of python dictionaries

    def __init__(self, testname, testfunc, varlist):
        self.params = varlist
        super(Qusbdual, self).__init__(testfunc)
        self._testMethodDoc = testname
        if "repetitions" in varlist:
            self.__repetitions = varlist["repetitions"]
        else:
            raise Exception('repetitions param inside Qusbdual must be defined')
        self.__resultlist = []

    def execute(self):
        # check if file-as-filesystem exists
        if not os.path.isfile('/var/lib/hwtest-files/mass-otg-test.img'):
            self.fail("failed: Unable to find file-as-filesystem image.")
        # generate mass storage gadget
        p = sh.modprobe("g_mass_storage", "file=/var/lib/hwtest-files/mass-otg-test.img")
        if p.exit_code != 0:
            self.fail("failed: Unable to create a mass storage gadget.")
        # find the mass storage device
        try:
            p = sh.grep(sh.lsblk("-So", "NAME,VENDOR"), "Linux")
        except sh.ErrorReturnCode as e:
            self.fail("failed: could not find any mass storage gadget")
        device = p.stdout.decode().split(" ")[0]
        # mount the mass storage gadget
        sh.mkdir("-p", "/tmp/station/hdd_gadget")
        p = sh.mount("-o", "ro", "/dev/" + device, "/tmp/station/hdd_gadget")
        if p.exit_code != 0:
            self.fail("failed: Unable to mount the mass storage gadget.")
        # execute test
        for i in range(self.__repetitions):
            # copy files
            try:
                p = sh.cp("/tmp/station/hdd_gadget/usb-test.bin", "/tmp/station/hdd_gadget/usb-test.bin.md5",
                          "/tmp/stationnfs")
            except sh.ErrorReturnCode as e:
                sh.umount("/tmp/station/hdd_gadget")
                sh.rmdir("/tmp/station/hdd_gadget")
                self.fail("failed: Unable to copy files through USB.")
            # Check md5
            try:
                p = sh.md5sum("/tmp/stationnfs/usb-test.bin")
            except sh.ErrorReturnCode as e:
                sh.umount("/tmp/station/hdd_gadget")
                sh.rmdir("/tmp/station/hdd_gadget")
                self.fail("failed: Unable to calculate MD5 of the copied file.")
            newmd5 = p.stdout.decode().split(" ")[0]
            with open('/tmp/station/hdd_gadget/usb-test.bin.md5', 'r') as outfile:
                oldmd5 = outfile.read()
            outfile.close()
            if newmd5 != oldmd5:
                sh.umount("/tmp/station/hdd_gadget")
                sh.rmdir("/tmp/station/hdd_gadget")
                self.fail("failed: MD5 check failed.")
            # delete copied files
            sh.rm("-f", "/tmp/stationnfs/usb-test.bin", "/tmp/stationnfs/usb-test.bin.md5")
        # Finish
        sh.umount("/tmp/station/hdd_gadget")
        sh.rmdir("/tmp/station/hdd_gadget")

    def getresults(self):
        return self.__resultlist

    def gettextresult(self):
        return ""