#!/usr/bin/env python

import os
import subprocess
import sys


def quit():
	print("OK, then do necessary steps and see you soon.")
	sys.exit(1)


def motd(termsize, settings):
	print("HOI, this is the 'Arch w/ maride flavour' install script (chainloader)")
	print("Hope you used TLS...")
	_separator(termsize)
	
	print("Things you should've set up already:")
	print(" * Your keyboard layout (consider passwords!)")
	print(" * Any RAID setup that you are planning to set up")
	print(" * An internet connection (DHCP or static, idc...)")
	
	answer = _ask("Did you set that up?", [ "yes", "no" ])
	
	if answer == "no":
		quit()

	_separator(termsize)


def efibios(termsize, settings):
	print("Please choose the installation/startup method.")
	print("Note that BIOS is required for VirtalBox hosts due a long-time unfixed bug.")
	print("It's possible that you need to change Mainboard settings for EFI. (But it's recommended!)")
	settings["bootmethod"] = _ask("Do you want to install on EFI or BIOS?", [ "EFI", "BIOS" ])
	_separator(termsize)


def blockdevice(termsize, settings):
	print("Please enter the full path to the block device the installation should take place on: (e.g. /dev/sda)")
	print("Make sure to choose a drive, not a partition.")
	print("Here's a list of devices that may be the right:")
	settings["blockdevice"] = _ask("Install where?", os.listdir("/sys/block/"), enforce=False)
	_separator(termsize)


def cryptroot(termsize, settings):
	print("Do you want to encrypt your root partition?")
	print("Please note that there is no way to recover your data if you forget your password.")
	settings["cryptroot"] = _ask("Encrypt root?", [ "yes", "no" ])
	_separator(termsize)


def rundir(termsize, settings, directory, validation_suffix, subfile="", ask=False):
	for filename in sorted(os.listdir(directory)):
		if filename[-len(validation_suffix):] == validation_suffix:
			# Run loop
			run = True
			while run:
				if ask and _ask("Do you want to run %s?" % (filename), [ "yes", "no" ]) == "no":
					run = False
					continue

				_separator(termsize)
				print("Running '%s'" % (filename))

				if subfile:
					executable = os.path.join(directory, filename, subfile)
				else:
					executable = os.path.join(directory, filename)

				with subprocess.Popen([executable], env=settings) as process:
					# Wait for process termination
					process.wait()
					if process.returncode > 0:
						# Woops, check failed somehow
						print("Executable %s returned non-null error code %i." % (executable, process.returncode))
						answer = _ask("Do you want to re-run the executable, skip the check or abort the installation?", [ "run", "skip", "abort"])
						if answer == "run":
							# doesn't matter, run is already 'True'
							continue
						elif answer == "skip":
							run = False
						elif answer == "abort":
							quit()
					else:
						run = False
		else:
			print("Uh. Found this executable: '%s' (Not executing)" % (filename))

	_separator(termsize)


def finish(termsize, settings):
	_separator(termsize)
	if _ask("Finished! \\o/ reboot now?", [ "yes", "no" ]) == "yes":
		os.system("reboot")


def _separator(termsize):
	print("~" * termsize["cols"])


def _ask(question, choices, enforce=True):
	while True:
		print("=> %s (%s) " % (question, ", ".join(choices)))
		answer = sys.stdin.readline()[:-1]
		if answer in choices or not enforce:
			return answer


def main():
	rows, columns = os.popen('stty size', 'r').read().split()
	termsize = {
		"rows": int(rows),
		"cols": int(columns)
	}
	settings = {}

	motd(termsize, settings)
	efibios(termsize, settings)
	blockdevice(termsize, settings)
	cryptroot(termsize, settings)
	rundir(termsize, settings, "checks", ".check")
	rundir(termsize, settings, "steps", ".step")
	rundir(termsize, settings, "flavours", ".flavour", "install.sh", ask=True)
	finish(termsize, settings)


if __name__ == '__main__':
	main()