#!/usr/bin/python3

# SPDX-License-Identifier: LGPL-3.0-or-later
# Copyright (c) 2020 Daniel Thompson

import argparse
import io
import random
import os.path
import pexpect
import time
import string
import sys

def pbar(iterable, quiet=False):
    step = 100 / len(iterable)
    for i, v in enumerate(iterable):
        if not quiet:
            percent = round(step * i, 1)
            bar = int(percent) // 2
            print(f'[{"#"*bar}{"."*(50-bar)}] {percent}%', end='\r', flush=True)
        yield v
    if not quiet:
        print(f'[{"#"*50}] 100% ')

def sync(c):
    """Stop the watch and synchronize with the command prompt.

    Sending a random print ensure the final export (of the prompt)
    does not accidentally match a previously issued prompt.
    """
    tag = ''.join([random.choice(string.ascii_uppercase) for i in range(6)])

    c.send('\x03')
    c.expect('>>> ')
    c.sendline(f'print("{tag[:3]}""{tag[3:]}")')
    c.expect(tag)
    c.expect('>>> ')

def unsync(c):
    """Set the watch running again.

    There must be an expect (or a sleep) since if we kill the subordinate
    process too early then the sendline will not have completed.
    """
    c.sendline('wasp.system.run()')
    c.expect(['Watch is running, use Ctrl-C to stop',
              'Watch already running in the background'])
    c.send('\x18')

def paste(c, f, verbose=False, chunk=None):
    docstring = False

    tosend = []

    for ln in f.readlines():
        ln = ln.rstrip()

        # This is a bit loose (definitely not PEP-257 compliant) but
        # is enough for most code.
        if ln.lstrip().startswith('"""'):
            docstring = True
        if docstring:
            if ln.rstrip().endswith('"""'):
                docstring = False
            continue

        if ln.lstrip().startswith('#'):
            continue

        if ln.strip() == '':
            continue

        tosend.append(ln)

    for ln in pbar(tosend, verbose):
        if chunk and ln.startswith('class'):
            chunk()

        c.sendline(ln)

        choice = c.expect(['=== ', 'FATAL: uncaught exception [0-9a-f\r]*\n'])
        if choice == 1:
            # Capture and display the error message, then exit
            if not verbose:
                print('\n~~~')
            while choice == 1:
                if not verbose:
                    print(c.match.group(0).rstrip(), file=sys.stderr)
                choice = c.expect([pexpect.TIMEOUT, '.*\n'], timeout=2)
            if not verbose:
                print('~~~')
            print('\nPlease reboot your device', file=sys.stderr)
            sys.exit(16)

def print_log(logfile):
    lines = logfile.getvalue().split('\n')
    lines = [ l.strip('\x04\r') for l in lines ]

    output = [ l for l in lines if l and l != '>>> ' ]
    if output:
        print('~~~')
        print('\n'.join(output))
        print('~~~')

def handle_eval(c, cmd):
    verbose = bool(c.logfile)

    c.send('\x05')
    c.expect('=== ')
    c.sendline(cmd)
    c.expect('=== ')

    if not verbose:
        c.logfile = io.StringIO()
    c.send('\x04')
    c.expect('>>> ')
    if not verbose:
        print_log(c.logfile)
        c.logfile.close()
        c.logfile = None

def handle_exec(c, fname):
    verbose = bool(c.logfile)

    log = io.StringIO()

    def chunk():
        if not verbose:
            c.logfile = log
        c.send('\x04')
        c.expect('>>> ')
        if not verbose:
            c.logfile = None
        c.send('\x05')
        c.expect('=== ')

    with open(fname) as f:
        if not verbose:
            print(f'Preparing to run {fname}:')

        c.send('\x05')
        c.expect('=== ')

        paste(c, f, verbose, chunk)

        if not verbose:
            c.logfile = log
        c.send('\x04')
        c.expect('>>> ')
        if not verbose:
            c.logfile = None

    print_log(log)
    log.close()

def handle_reset(c, ota=False):
    cmd = 'reset'
    if ota:
        cmd = 'enter_ota_dfu'

    c.send('\x05')
    c.expect('=== ')
    c.sendline('import machine')
    c.expect('=== ')
    c.sendline(f'machine.{cmd}()')
    c.expect('=== ')
    c.send('\x04')

def handle_rtc(c):
    # Wait for the clock to tick over to the next second
    now = then = time.localtime()
    while now[5] == then[5]:
        now = time.localtime()

    # Set the time
    c.sendline(f'watch.rtc.set_localtime(({now[0]}, {now[1]}, {now[2]}, {now[3]}, {now[4]}, {now[5]}, {now[6]}, {now[7]}))')
    c.expect('>>> ')

def check_rtc(c):
    c.sendline('print(watch.rtc.get_localtime())')
    c.expect('\(([0-9]+), ([0-9]+), ([0-9]+), ([0-9]+), ([0-9]+), ([0-9]+), ([0-9]+), ([0-9]+)\)')
    t = time.localtime()

    watch_hms = (int(c.match[4]), int(c.match[5]), int(c.match[6]))
    watch_str = f'{watch_hms[0]:02d}:{watch_hms[1]:02d}:{watch_hms[2]:02d}'
    host_hms = (t.tm_hour, t.tm_min, t.tm_sec)
    host_str = f'{host_hms[0]:02d}:{host_hms[1]:02d}:{host_hms[2]:02d}'
    delta = 3600 * (host_hms[0] - watch_hms[0]) + \
              60 * (host_hms[1] - watch_hms[1]) + \
                   (host_hms[2] - watch_hms[2])
    print(f"PC <-> watch:  {watch_str} <-> {host_str} (delta {delta})")

    c.expect('>>> ')

def handle_binary_upload(c, fname):
    verbose = bool(c.logfile)

    c.sendline(f'f = open("{os.path.basename(fname)}", "wb")')
    c.expect('>>> ')

    # Absorb the file to be uploaded
    with open(fname, 'rb') as f:
        data = f.read()
    chunksz = 24
    nchunks = len(data) // chunksz
    lastchunk = len(data) % chunksz

    if not verbose:
        print(f'Uploading {fname}:')

    # Send the data
    for i in pbar(range(0, chunksz*nchunks, chunksz), verbose):
        c.sendline(f'f.write({repr(data[i:i+chunksz])})')
        c.expect('>>> ')
    if lastchunk:
        c.sendline(f'f.write({repr(data[-lastchunk:])})')
        c.expect('>>> ')

    c.sendline('f.close()')
    c.expect('>>> ')

def handle_upload(c, fname):
    verbose = bool(c.logfile)

    c.sendline('from shell import upload')
    c.expect('>>> ')

    with open(fname) as f:
        if not verbose:
            print(f'Uploading {fname}:')

        c.sendline(f'upload("{os.path.basename(fname)}")')
        c.expect('=== ')
        paste(c, f, verbose)
        c.send('\x04')

        c.expect('>>> ')

if __name__ == '__main__':
    parser = argparse.ArgumentParser(
            description='Wasp-os command and control client')
    parser.add_argument('--bootloader', action='store_true',
            help="Reboot into the bootloader mode for OTA update")
    parser.add_argument('--binary', action='store_true',
            help="Enable non-ASCII mode for suitable commands (such as upload)")
    parser.add_argument('--console', action='store_true',
            help='Launch a REPL session')
    parser.add_argument('--check-rtc', action='store_true',
            help='Compare workstation and watch times')
    parser.add_argument('--device',
            help='Connect only to a specific named device (or MAC address)')
    parser.add_argument('--exec',
            help='Execute the contents of a file')
    parser.add_argument('--eval',
            help='Execute the provided python string')
    parser.add_argument('--reset', action='store_true',
            help="Reboot the device (and don't stay in bootloader mode)")
    parser.add_argument('--ota',
            help="Deliver an OTA update to the device")
    parser.add_argument('--rtc', action='store_true',
            help='Set the time on the wasp-os device')
    parser.add_argument('--upload',
            help='Copy the specified file to the wasp-os device')
    parser.add_argument('--verbose', action='store_true',
            help='Log interaction with the wasp-os device')

    args = parser.parse_args()

    if args.device:
        if ':' in args.device:
            device_args = ' --address ' + args.device
        else:
            device_args = ' --device ' + args.device
    else:
        device_args = ''

    pynus = os.path.dirname(sys.argv[0]) + '/pynus/pynus.py' + device_args
    console = pexpect.spawn(pynus, encoding='UTF-8')
    if args.verbose:
        console.logfile = sys.stdout

    console.expect('Connect.*\(([0-9A-F:]*)\)')
    macaddr = console.match.group(1)
    console.expect('Exit console using Ctrl-X')
    time.sleep(0.5)
    sync(console)

    if args.rtc:
        handle_rtc(console)

    if args.check_rtc:
        check_rtc(console)

    if args.exec:
        handle_exec(console, args.exec)

    if args.eval:
        handle_eval(console, args.eval)

    if args.upload:
        if args.binary:
            handle_binary_upload(console, args.upload)
        else:
            handle_upload(console, args.upload)

    if args.console:
        console.close()
        argv = pynus.split()
        os.execv(argv[0], argv)

    if args.ota:
        handle_reset(console, ota=True)
        time.sleep(0.5)
        dfu = os.path.dirname(sys.argv[0]) + '/ota-dfu/dfu.py'
        os.execl(dfu, dfu, '-z', args.ota, '-a', macaddr, '--legacy')

    if args.reset:
        handle_reset(console)
        sys.exit(0)

    if args.bootloader:
        handle_reset(console, ota=True)
        sys.exit(0)

    unsync(console)