from base import Task
from common import phases
from common.exceptions import TaskError
from common.tools import log_check_call
from common.filesystem import filesystem


class FormatVolume(Task):
	description = 'Formatting the volume'
	phase = phases.volume_preparation

	def run(self, info):
		mkmount = ['/usr/bin/qemu-img', 'create', '-f', 'raw', info.manifest.bootstrapper['image_file'], str(info.manifest.volume['size'])+'M']
		log_check_call(mkmount)

		loopcmd = ['/sbin/losetup', '/dev/loop0', info.manifest.bootstrapper['image_file']]
		log_check_call(loopcmd)

		# parted
		log_check_call(['parted', '-a', 'optimal', '-s', '/dev/loop0', "mklabel", "msdos"])
		log_check_call(['parted', '-a', 'optimal', '-s', '/dev/loop0', "--", "mkpart", "primary", "ext4", "32k", "-1"])
		log_check_call(['parted', '-s', '/dev/loop0', "--", "set", "1", "boot", "on"])

		log_check_call(['kpartx', '-a', '-v', '/dev/loop0'])
		mkfs = ['/sbin/mkfs.{fs}'.format(fs=info.manifest.volume['filesystem']), '-m', '1', '-v', '/dev/mapper/loop0p1']
		log_check_call(mkfs)


class TuneVolumeFS(Task):
	description = 'Tuning the bootstrap volume filesystem'
	phase = phases.volume_preparation
	after = [FormatVolume]

	def run(self, info):
		dev_path = '/dev/mapper/loop0p1'
		# Disable the time based filesystem check
		log_check_call(['/sbin/tune2fs', '-i', '0', dev_path])


class MountVolume(Task):
	description = 'Mounting the bootstrap volume'
	phase = phases.volume_mounting
	after = [filesystem.CreateMountDir]

	def run(self, info):
		with open('/proc/mounts') as mounts:
			for mount in mounts:
				if info.root in mount:
					msg = 'Something is already mounted at {root}'.format(root=info.root)
					raise TaskError(msg)

		log_check_call(['/bin/mount', '-t', info.manifest.volume['filesystem'], '/dev/mapper/loop0p1', info.root])


class UnmountVolume(Task):
	description = 'Unmounting the bootstrap volume'
	phase = phases.volume_unmounting
	after = [filesystem.UnmountSpecials]

	def run(self, info):
		log_check_call(['/bin/umount', info.root])
		log_check_call(['kpartx', '-d', info.manifest.bootstrapper['image_file']])


class ModifyFstab(Task):
	description = 'Adding root volume to the fstab'
	phase = phases.system_modification

	def run(self, info):
		import os.path
		mount_opts = ['defaults']
		if info.manifest.volume['filesystem'].lower() in ['ext2', 'ext3', 'ext4']:
			mount_opts.append('barrier=0')
		if info.manifest.volume['filesystem'].lower() == 'xfs':
			mount_opts.append('nobarrier')
		fstab_path = os.path.join(info.root, 'etc/fstab')
		with open(fstab_path, 'a') as fstab:
			device = '/dev/sda1'
			if info.manifest.virtualization == 'virtio':
				device = '/dev/vda1'

			fstab.write('{device} /     {filesystem}    {mount_opts} 1 1\n'
			            .format(device=device,
			                    filesystem=info.manifest.volume['filesystem'].lower(),
			                    mount_opts=','.join(mount_opts)))