script:Taskwarrior wrapper for intelligently parses datetime format (due, scheduled, etc.) in human language.

taskwarrior-datetime-parser-wrapper

#!/bin/bash
# By soraxas
# This file shall be the wrapper for taskwarrior
# Do something like:
# alias task="taskwarrior-datetime-parser-wrapper"

# argunments that contain datetime format
TIME_FORMAT="(^|\W)(until|wait|due|scheduled):"

TASK="$(which task)"

if [ -z "$TASK" ]; then
  echo "Binary task not found!"
  exit 1
fi

# check if any argunment matches it
if ! echo "$@" | grep -qP "$TIME_FORMAT"; then
  # no date format in args.
  "$TASK" "$@"
  exit $?
fi

# use python wrapper to intelligently parse datetime
# The reason to firt use a bash script to check is because
# python has a slow startup time. Which would slow down even
# the very basic command without any args.
# Therefore, this method ensures that python process is called
# only when it is necessary (i.e. when datetime format presents)
# and needs potential parsing.

PYTHON="$(which python3)"

# embed the python script here to avoid having multiple files.
"$PYTHON" -c '
import sys
import datetime
import dateutil.parser
import subprocess


def parse_with_dateutil(inputs, ensure_future=True):
    # use dateutil to intelligently parse datetime.
    parser = dateutil.parser.parser()
    try:
        out = parser.parse(inputs)
        if out.hour == 0 and out.minute == 0:
            # skip adding time if its the default 00:00
            # DATE_FORMAT = "YYYY-MM-DD"
            DATEUTIL_FORMAT = "%Y-%m-%d"
        else:
            # DATE_FORMAT = "YYYY-MM-DDThh:mm"
            DATEUTIL_FORMAT = "%Y-%m-%dT%H:%M%z"
    except ValueError:
        # dateutil couldnt understand it. Probably is TWs builtin special date
        return None

    if ensure_future:
        # ensure the target is in the future
        now = datetime.datetime.now()
        if now > out:
            # check that if user had omitted some settings, make the default to be the
            # immediate next instance of the given ambigious time.
            user_provided = parser._parse(inputs)[0]
            if getattr(user_provided, "day") is None:
                out = out + dateutil.relativedelta.relativedelta(days=1)
            elif getattr(user_provided, "month") is None:
                out = out + dateutil.relativedelta.relativedelta(months=1)
            elif getattr(user_provided, "year") is None:
                out = out + dateutil.relativedelta.relativedelta(years=1)

    return out.strftime(DATEUTIL_FORMAT)

class TWCommandline:
    def __init__(self, argv):
        """This class is for easy editing argv."""
        self.argv = []
        for arg in argv[1:]:  # first arg is this script
            # try different way to separatethe arg
            for sep in ("=", ":"):
                if len(arg.split(sep)) == 2:
                    _tmp = arg.split(sep)
                    self.argv.append([_tmp[0], sep, _tmp[1]])
                    break
            else:  # add the original argunment
                self.argv.append(arg)

    def build_cmd(self):
        return ["".join(a) if isinstance(a, list) else a for a in self.argv]


twc = TWCommandline(sys.argv)

# dont do any modification if a custom dateformat is used
if not any(arg[0] == "rc.dateformat" for arg in twc.argv):
    # else, use a dateutil-powered parser.
    timeformat = ("until", "wait", "due", "scheduled")
    for arg in twc.argv:
        if arg[0] in timeformat:
            result = parse_with_dateutil(arg[2])
            if result is not None:
                # notify user of the auto-parsing
                print("> Auto-converted `{}:{}` -> `{}:{}`".format(
                    arg[0], arg[2], arg[0], result
                ))
                # apply new parsed datetime
                arg[2] = result

exit(subprocess.run(["'"$TASK"'"] + twc.build_cmd()).returncode)
' $@

exit $?