#!/usr/bin/python

# TODO:
# - -h text
# - output to clay

import os
import sys
import logging
import json
import requests
import argparse
import base64

PORT = os.environ.get('LENS_PORT', 12321)

logging.basicConfig(level=logging.WARNING,
                    format='%(levelname)s %(funcName)s %(lineno)s - %(message)s',
                    stream=sys.stderr)

logging.debug(['sys.argv', sys.argv])

def preprocess_args(old_args):
    """Split out []

    We use [] to delimit tuples.  The following syntaxes are all equivalent:

    --  --open --open a b --close --open c d --close --close
    --  [ [ a b ] [ c d ] ]
    --  [ [a b] [c d] ]
    --  [[a b] [c d]]
    --  etc

    We don't allow [[a b][c d]].  The rule is that we accept zero or more [ at
    the beginning of a token and zero or more ] at the end of a token.

    In this function, we convert all legal syntaxes to as if they were entered
    as in the first example above.  This allows them to be parsed by a
    relatively sane argparse system.
    """

    if old_args == []:
        return []
    if old_args[0][0] == '[':
        if len(old_args[0]) > 1:
            return ['--open'] + preprocess_args([old_args[0][1:]] + old_args[1:])
        else:
            return ['--open'] + preprocess_args(old_args[1:])
    if old_args[0][-1] == ']':
        if len(old_args[0]) > 1:
            return preprocess_args([old_args[0][:-1]]) + \
                    ['--close'] + preprocess_args(old_args[1:])
        else:
            return ['--close'] + preprocess_args(old_args[1:])
    return [old_args[0]] + preprocess_args(old_args[1:])

args = preprocess_args(sys.argv[1:])

logging.debug(['preprocessed', args])


class sourceAction(argparse.Action):
    """Handle source flag.

    This is all the 'primitive' source flags -- no nesting, no tuple stuff,
    just one flag with one argument.

    Besides the normal argparse.Action arguments, we require the following named
    argument:

    -- which='foo'.  Since all source flags use res.source, this specifies the
        key of the entry for this flag.
    """

    def __init__(self, option_strings, dest, **kwargs):
        self.which = kwargs['which']
        del kwargs['which']
        super(sourceAction, self).__init__(option_strings, dest, **kwargs)

    def __call__(self, parser, res, new_value, option_string):
        logging.debug('%r %r' % (new_value, option_string))
        logging.debug('source %s' % res.source)
        logging.debug('level %s' % res.level)

        if res.source is not None:
            def help(source, level):
                logging.debug('source %s' % source)
                logging.debug('level %s' % level)
                if not isinstance(source, list):
                    raise ValueError('Already specified one source')
                elif level == 0:
                    raise ValueError('Already specified a source %r %s' % (source, level))
                elif level == 1:
                    return source + [self.construct_value(new_value)]
                else:
                    return source[:-1] + [help(source[-1], level - 1)]
            res.source = help(res.source, res.level)
        else:
            res.source = \
              self.construct_value(new_value)

        logging.debug(res.source)

    def construct_value(self, new_value):
        if new_value == '-':
            return self.construct_value(''.join(sys.stdin))
        elif new_value[0:2] == '@@':
            with open(new_value[2:]) as f:
              content = f.readlines()
            return self.construct_value(''.join(content))
        else:
           return {self.which: new_value}

class transformerAction(argparse.Action):
    """Handle transformer flag.

    This is all the tranformer flags.  Each flag takes one argument and
    transforms the previous source.

    Besides the normal argparse.Action arguments, we require the following named
    arguments:

    -- which='foo'.  Since all source flags use res.source, this specifies the
        key of the entry for this flag.
    
    -- nesting='foo'.  The key for the argument is 'foo'.
    """

    def __init__(self, option_strings, dest, **kwargs):
        self.which = kwargs['which']
        self.nesting = kwargs['nesting']
        del kwargs['which']
        del kwargs['nesting']
        super(transformerAction, self).__init__(option_strings, dest, **kwargs)

    def __call__(self, parser, res, new_value, option_string):
        logging.debug('%r %r' % (new_value, option_string))
        logging.debug('source %s' % res.source)
        logging.debug('level %s' % res.level)

        if res.source is None:
            raise ValueError('Need source before transformer')
        else:
            def help(source, level):
                logging.debug('source %s' % source)
                logging.debug('level %s' % level)
                if level == 0 or level is None:
                    return {self.which: {self.nesting: new_value, "next": source}}
                elif not isinstance(source, list):
                    raise ValueError('Already specified one source')
                else:
                    return source[:-1] + [help(source[-1], level - 1)]
            res.source = help(res.source, res.level)

        logging.debug(res.source)

class openAction(argparse.Action):
    """Handle open tuple.

    Opens a source tuple.  Can only exist in the same places as any other
    source.
    """

    def __init__(self, option_strings, dest, **kwargs):
        super(openAction, self).__init__(option_strings, dest, **kwargs)

    def __call__(self, parser, res, new_value, option_string):
        if res.level is None:
            res.level = 0

        logging.debug('source %s' % res.source)
        logging.debug('level %s' % res.level)

        if res.source is None:
            res.source = []
            res.level = 1
            return

        def help(source, level):
            if not isinstance(source, list):
                raise ValueError('Starting tuple after source is finished')
            if level == 1:
                return (source + [[]], level + 1)
            elif level > 1:
                rsource, rlevel = help(source[-1], level - 1)
                return (source[:-1] + [rsource], rlevel + 1)
            else:
                raise ValueError('opening strange level %r %s' % (source, level))

        res.source, res.level = help(res.source, res.level)

class closeAction(argparse.Action):
    """Handle close tuple.

    Closes a source tuple.  Can only exist when a tuple is already open.
    """

    def __init__(self, option_strings, dest, **kwargs):
        super(closeAction, self).__init__(option_strings, dest, **kwargs)

    def __call__(self, parser, res, new_value, option_string):
        if res.level is None:
            raise ValueError('Ending tuple before starting one')

        logging.debug('level %s' % res.level)

        if res.source is None:
            raise ValueError('Ending tuple with empty source')

        def help(source, level):
            if not isinstance(source, list):
                raise ValueError('Ending tuple that isn\'t a tuple')
            if level == 1:
                return level - 1
            elif level > 1:
                return help(source[-1], level - 1) + 1
            else:
                raise ValueError('closing strange level %r %s' % (source, level))

        res.level = help(res.source, res.level)

        logging.debug('level %s' % res.level)

class sinkAction(argparse.Action):
    """Handle sink flag.

    We expect only one sinkAction to ever be executed.  We recommend using
    mutually_exclusive_group's.

    Besides the normal action flags, we require the following named argument:

    -- which='foo'.  Since all sink flags use res.sink, this specifies the key
        of the entry for this flag.
    """

    def __init__(self, option_strings, dest, **kwargs):
        self.which = kwargs['which']
        del kwargs['which']
        super(sinkAction, self).__init__(option_strings, dest, **kwargs)

    def __call__(self, parser, res, new_value, option_string):
        res.sink = self.construct_value(new_value)

        logging.debug(res.sink)

    def construct_value(self, new_value):
        if self.which == 'output-file':
            return {self.which: new_value[::-1].replace('.','/',1)[::-1]}
        else:
            return {self.which: new_value}

parser = argparse.ArgumentParser(description='headless urbit')
parser.add_argument('-d', '--dojo', which='dojo',
                    metavar='command-line',
                    help='run dojo command',
                    action=sourceAction, dest='source')
parser.add_argument('-D', '--data', which='data',
                    metavar='text',
                    help='literal text data',
                    action=sourceAction)
parser.add_argument('-c', '--clay', which='clay',
                    metavar='clay-path',
                    help='load data from clay',
                    action=sourceAction)
parser.add_argument('-u', '--url', which='url',
                    metavar='url',
                    help='pull data from url',
                    action=sourceAction)
parser.add_argument('-a', '--api', which='api',
                    metavar='command',
                    help='get data from api',
                    action=sourceAction)
parser.add_argument('-g', '--get-api', which='get-api',
                    metavar='api:endpoint',
                    help='get data from api endpoint',
                    action=sourceAction)
parser.add_argument('-l', '--listen-api', which='listen-api',
                    metavar='api:event',
                    help='listen to event from api',
                    action=sourceAction)
parser.add_argument('-m', '--mark', which='as',
                    metavar='mark',
                    help='transform a source to another mark',
                    nesting='mark',
                    action=transformerAction)
parser.add_argument('-H', '--hoon', which='hoon',
                    metavar='code',
                    help='transform a source by hoon code',
                    nesting='code',
                    action=transformerAction)
parser.add_argument('--open',
                    nargs=0,
                    help='start tuple',
                    action=openAction, dest='level')
parser.add_argument('--close',
                    nargs=0,
                    help='stop tuple',
                    action=closeAction)

sinks = parser.add_mutually_exclusive_group()
sinks.add_argument('-s', '--stdout', const={'stdout': None},
                   default={'stdout': None},
                   action='store_const', dest='sink')
sinks.add_argument('-f', '--output-file', which='output-file',
                   metavar='path',
                   action=sinkAction)
sinks.add_argument('-C', '--output-clay', which='output-clay',
                   metavar='clay-path',
                   action=sinkAction)
sinks.add_argument('-U', '--output-url', which='url',
                   metavar='url',
                   action=sinkAction)
sinks.add_argument('-t', '--to-api', which='to-api',
                   metavar='api-command',
                   action=sinkAction)
sinks.add_argument('-n', '--send-api', which='send-api',
                   metavar='api:endpoint',
                   action=sinkAction)
sinks.add_argument('-x', '--command', which='command',
                   metavar='command',
                   action=sinkAction)
sinks.add_argument('-p', '--app', which='app',
                   metavar='app',
                   action=sinkAction)


args = parser.parse_args(args)


if args.source is None:
    args.source = {"data": ''.join(sys.stdin)}

payload = {"source": args.source, "sink": args.sink}
logging.debug(['payload', json.dumps(payload)])

url = "http://localhost:%s" % PORT
r = requests.post(url, data=json.dumps(payload))
if r.text[0] == '"':
    print r.text[1:-1].decode('string_escape')
elif r.text[0] == '{':
    # print r.text
    json_data = json.loads(r.text)
    logging.debug(json_data)
    with open(json_data['file'][:0:-1].replace('/','.',1)[::-1], 'w') as f:
      f.write(base64.b64decode(json_data['data']))
else:
    logging.warn("unrecognized response")
    print r.text