#!/usr/bin/env python3
#
# mmgen = Multi-Mode GENerator, command-line Bitcoin cold storage solution
# Copyright (C)2013-2023 The MMGen Project <mmgen@tuta.io>
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.

"""
test.include.pexpect: pexpect implementation for MMGen test suites
"""

import sys,time
from mmgen.color import red,yellow,green,cyan
from mmgen.util import msg,msg_r,rmsg,die
from .common import cfg,vmsg,vmsg_r,getrandstr,strip_ansi_escapes

try:
	import pexpect
	from pexpect.popen_spawn import PopenSpawn
except ImportError as e:
	die(2,red(f'Pexpect module is missing.  Cannnot run test suite ({e!r})'))

def debug_pexpect_msg(p):
	msg('\n{}{}{}'.format( red('BEFORE ['), p.before, red(']') ))
	msg('{}{}{}'.format( red('MATCH ['), p.after, red(']') ))

NL = '\n'

class MMGenPexpect:

	def __init__(
			self,
			args,
			no_output     = False,
			spawn_env     = None,
			pexpect_spawn = False,
			send_delay    = None,
			timeout       = None,
			direct_exec   = False ):

		self.pexpect_spawn = pexpect_spawn
		self.send_delay = send_delay
		self.req_exit_val = 0
		self.skip_ok = False
		self.sent_value = None
		self.spawn_env = spawn_env

		if direct_exec or cfg.direct_exec:
			from subprocess import Popen,DEVNULL
			redir = DEVNULL if (no_output or not cfg.exact_output) else None
			self.ep = Popen([args[0]] + args[1:], stderr=redir, env=spawn_env )
		else:
			timeout = int(timeout or cfg.pexpect_timeout or 0) or (60,5)[bool(cfg.debug_pexpect)]
			if pexpect_spawn:
				self.p = pexpect.spawn(args[0],args[1:],encoding='utf8',timeout=timeout,env=spawn_env)
			else:
				self.p = PopenSpawn(args,encoding='utf8',timeout=timeout,env=spawn_env)

			if cfg.exact_output:
				self.p.logfile = sys.stdout

	def do_decrypt_ka_data(
			self,
			pw,
			desc         = 'key-address data',
			check        = True,
			have_yes_opt = False):
		self.passphrase(desc,pw)
		if not have_yes_opt:
			self.expect('Check key-to-address validity? (y/N): ',('n','y')[check])

	def view_tx(self,view):
		self.expect(r'View.* transaction.*\? .*: ',view,regex=True)
		if view not in 'n\n':
			self.expect('to continue: ','\n')

	def do_comment(self,add_comment,has_label=False):
		p = ('Add a comment to transaction','Edit transaction comment')[has_label]
		self.expect(f'{p}? (y/N): ',('n','y')[bool(add_comment)])
		if add_comment:
			self.expect('Comment: ',add_comment+'\n')

	def ok(self):
		if not self.pexpect_spawn:
			self.p.sendeof()
		self.p.read()
		ret = self.p.wait()
		if ret != self.req_exit_val and not cfg.coverage:
			die( 'TestSuiteSpawnedScriptException', f'Spawned script exited with value {ret}' )
		if cfg.profile:
			return
		if not self.skip_ok:
			m = 'OK\n' if ret == 0 else f'OK[{ret}]\n'
			sys.stderr.write( green(m) if cfg.exact_output or cfg.verbose else ' '+m )
		return self

	def license(self):
		if self.spawn_env.get('MMGEN_NO_LICENSE'):
			return
		self.expect("'w' for conditions and warranty info, or 'c' to continue: ",'c')

	def label(self,label='Test Label (UTF-8) α'):
		self.expect('Enter a wallet label, or hit ENTER for no label: ',label+'\n')

	def usr_rand(self,num_chars):
		if cfg.usr_random:
			self.interactive()
			self.send('\n')
		else:
			rand_chars = list(getrandstr(num_chars,no_space=True))
			vmsg_r('SEND ')
			while rand_chars:
				ch = rand_chars.pop(0)
				msg_r(yellow(ch)+' ' if cfg.verbose else '+')
				self.expect('left: ',ch,delay=0.005)
			self.expect('ENTER to continue: ','\n')

	def passphrase_new(self,desc,passphrase):
		self.expect(f'Enter passphrase for {desc}: ',passphrase+'\n')
		self.expect('Repeat passphrase: ',passphrase+'\n')

	def passphrase(self,desc,passphrase,pwtype=''):
		if pwtype:
			pwtype += ' '
		self.expect(f'Enter {pwtype}passphrase for {desc}.*?: ',passphrase+'\n',regex=True)

	def hash_preset(self,desc,preset=''):
		self.expect(f'Enter hash preset for {desc}')
		self.expect('or hit ENTER .*?:',str(preset)+'\n',regex=True)

	def written_to_file(self,desc,overwrite_unlikely=False,query='Overwrite?  '):
		s1 = f'{desc} written to file '
		s2 = query + "Type uppercase 'YES' to confirm: "
		ret = self.expect(([s1,s2],s1)[overwrite_unlikely])
		if ret == 1:
			self.send('YES\n')
			return self.expect_getend("Overwriting file '").rstrip("'")
		self.expect(NL,nonl=True)
		outfile = self.p.before.strip().strip("'")
		if cfg.debug_pexpect:
			rmsg(f'Outfile [{outfile}]')
		vmsg('{} file: {}'.format( desc, cyan(outfile.replace('"',"")) ))
		return outfile

	def hincog_create(self,hincog_bytes):
		ret = self.expect(['Create? (Y/n): ',"'YES' to confirm: "])
		if ret == 0:
			self.send('\n')
			self.expect('Enter file size: ',str(hincog_bytes)+'\n')
		else:
			self.send('YES\n')
		return ret

	def no_overwrite(self):
		self.expect("Overwrite?  Type uppercase 'YES' to confirm: ",'\n')
		self.expect('Exiting at user request')

	def expect_getend(self,s,regex=False):
		self.expect(s,regex=regex,nonl=True)
		if cfg.debug_pexpect:
			debug_pexpect_msg(self.p)
		# readline() of partial lines doesn't work with PopenSpawn, so do this instead:
		self.expect(NL,nonl=True,silent=True)
		if cfg.debug_pexpect:
			debug_pexpect_msg(self.p)
		end = self.p.before.rstrip()
		if not cfg.debug:
			vmsg(f' ==> {cyan(end)}')
		return end

	def interactive(self):
		return self.p.interact() # interact() not available with popen_spawn

	def kill(self,signal):
		return self.p.kill(signal)

	def match_expect_list(self,expect_list,greedy=False):
		allrep = '.*' if greedy else '.*?'
		expect = (
			r'(\b|\s)' +
			fr'\s{allrep}\s'.join(s.replace(r'.',r'\.').replace(' ',r'\s+') for s in expect_list) +
			r'(\b|\s)' )
		import re
		m = re.search( expect, self.read(strip_color=True), re.DOTALL )
		assert m, f'No match found for regular expression {expect!r}'
		return m

	def expect(self,s,t='',delay=None,regex=False,nonl=False,silent=False):

		if not silent:
			if cfg.verbose:
				msg_r('EXPECT ' + yellow(str(s)))
			elif not cfg.exact_output:
				msg_r('+')

		try:
			ret = (self.p.expect_exact,self.p.expect)[bool(regex)](s) if s else 0
		except pexpect.TIMEOUT as e:
			if cfg.debug_pexpect:
				raise
			m1 = f'\nERROR.  Expect {s!r} timed out.  Exiting\n'
			m2 = f'before: [{self.p.before}]\n'
			m3 = f'sent value: [{self.sent_value}]' if self.sent_value is not None else ''
			raise pexpect.TIMEOUT(m1+m2+m3) from e

		if cfg.debug_pexpect:
			debug_pexpect_msg(self.p)

		if cfg.verbose and not isinstance(s,str):
			msg_r(f' ==> {ret} ')

		if ret == -1:
			die(4,f'Error.  Expect returned {ret}')
		else:
			if t:
				self.send(t,delay,s)
			else:
				if not nonl and not silent:
					vmsg('')
			return ret

	def send(self,t,delay=None,s=False):
		delay = delay or self.send_delay
		if delay:
			time.sleep(delay)
		ret = self.p.send(t) # returns num bytes written
		self.sent_value = t if ret else None
		if cfg.demo and delay:
			time.sleep(delay)
		if cfg.verbose:
			ls = '' if cfg.debug or not s else ' '
			es = '' if s else '  '
			yt = yellow('{!r}'.format( t.replace('\n',r'\n') ))
			msg(f'{ls}SEND {es}{yt}')
		return ret

	def read(self,n=-1,strip_color=False):
		return strip_ansi_escapes(self.p.read(n)).replace('\r','') if strip_color else self.p.read(n)

	def close(self):
		if self.pexpect_spawn:
			self.p.close()