tmsa

#!/usr/bin/env python3
# Time Management for Systems Administrators helper scripts
#
# Copyright (C) 2013 Mark Harrison
#
# Permission is hereby granted, free of charge, to any person obtaining a copy
# of this software and associated documentation files (the "Software"), to deal
# in the Software without restriction, including without limitation the rights
# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
# copies of the Software, and to permit persons to whom the Software is
# furnished to do so, subject to the following conditions:
#
# The above copyright notice and this permission notice shall be included in
# all copies or substantial portions of the Software.
#
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
# SOFTWARE.

import datetime
import glob
import os
import re
import sys

commands = {
    'bringforward': ["Bring forward any unmanaged tasks to today"],
    'bump': ["Bump a task to the next day", "For example, bump 2"],
    'bumpall': ["Bump all tasks to the next day"],
    'verify': ["Print out to do files that have unmanaged active tasks"],
    'tmsa': [
        "Time management for systems administrators helper script.",
        "Provides a set of commands to help with the Cycle, which",
        "makes use of daily to do lists.",
        "This command will create symlinks for the other commands"
    ]
}


def make_symlinks():
    "Makes symlinks for the various tmsa commands"
    os.chdir(os.environ["TODO_ACTIONS_DIR"])
    for command in commands:
        if command == 'tmsa':
            continue
        try:
            os.symlink('tmsa', command)
            print("Created symlink for %s" % command)
        except OSError as e:
            if e.errno == 17:
                print("Symlink for %s already created" % command)
            else:
                raise


def strip_priority(line):
    "Removes the priority, if any, from a todo item"
    return re.sub('^\([A-Z]\) ', '', line)

def undone_lines(fh):
    "Internal function to return lines in a file handle not marked as done."
    content = fh.readlines()
    undone_lines = [l for l in content if re.match('^(?!x \d{4}-\d{2}-\d{2})',l)]
    return undone_lines;


def find_unmanaged():
    "Find files with unmanaged active tasks"
    unmanaged = []
    os.chdir(os.environ["TODO_DIR"])
    now = datetime.datetime.now().replace(hour=0, minute=0, second=0,
                                          microsecond=0)
    for f in glob.glob("????-??-??.txt"):
        d, e = f.split(".")
        size = os.stat(f).st_size
        # Find the date-based files before today that contain any non-done items
        if datetime.datetime.strptime(d, "%Y-%m-%d") < now and size > 0:
            with open(f) as fh:
                if undone_lines(fh):
                   unmanaged.append(f)
    return unmanaged


def bump(from_file, to_file, line_num=None):
    "Bumps a task, or all if no line is provided"
    auto_archive = "TODOTXT_AUTO_ARCHIVE" in os.environ and \
        os.environ["TODOTXT_AUTO_ARCHIVE"] == "1"
    preserve_line_numbers = "TODOTXT_PRESERVE_LINE_NUMBERS" in \
        os.environ and os.environ["TODOTXT_PRESERVE_LINE_NUMBERS"] == "1"

    os.chdir(os.environ["TODO_DIR"])
    now = datetime.datetime.now()
    today = now.strftime("%Y-%m-%d")
    ifh = open(from_file)  # File to bump from
    ofh = open(to_file, "a")  # File to bump to
    tfh = open("%s.tmp" % from_file, "w")  # Temporary file
    if auto_archive:
        dfh = open("%s-done.txt" % from_file[:-4], "a")  # Done file
    else:
        dfh = tfh
    bumped = []
    for n, line in enumerate(undone_lines(ifh)):
        n += 1  # 1-indexed lines
        if not line_num or line_num == n:
            ## Bump the item
            # Copy line to today's file
            ofh.write(line)
            # Mark as done (and bumped) in the done file
            dfh.write("x %s %s bumped:%s\n" % (today,
                      strip_priority(line).rstrip(),
                      to_file[:-4]))
            if auto_archive and preserve_line_numbers and line_num:
                tfh.write("\n")
            bumped.append(line.rstrip())
        else:
            # Don't bump the item
            tfh.write(line)
    ifh.close()
    if auto_archive:
        dfh.close()
    ofh.close()
    tfh.close()
    # Now move the temp file (with the bumped entries remove) to the original
    # from file
    os.remove(from_file)
    os.rename("%s.tmp" % from_file, from_file)
    # Status message
    print("\n".join(bumped))
    if line_num:
        print("TODO: %s bumped from %s to %s" % (line_num, from_file, to_file))
    else:
        print("TODO: all items bumped from %s to %s" % (from_file, to_file))


def usage(command):
    if command in commands:
        print("    %s" % command)
        print("\n".join("      %s" % i for i in commands[command]))

if __name__ == '__main__':
    action = sys.argv[1]
    if action == 'usage':
        prog = os.path.basename(sys.argv[0])  # Identify command
        usage(prog)
        sys.exit(0)

    if action == 'verify':
        unmanaged = find_unmanaged()
        if unmanaged:
            print('\n'.join(sorted(find_unmanaged())))
        sys.exit(0)

    if action == 'bump' or action == 'bumpall':
        to_bump = None
        now = datetime.datetime.now()
        weekday = now.weekday()
        if weekday == '5':
            # Today is friday, skip to monday
            days = 3
        else:
            days = 1
        if action == 'bump':
            if len(sys.argv) < 3:
                usage('bump')
                sys.exit(1)
            try:
                to_bump = int(sys.argv[2])
                if len(sys.argv) == 4:
                    days = int(sys.argv[3])
            except ValueError:
                usage('bump')
                sys.exit(1)
        next_day = now + datetime.timedelta(days=days)
        today = now.strftime("%Y-%m-%d.txt")
        next_file = next_day.strftime("%Y-%m-%d.txt")
        bump(today, next_file, to_bump)
        sys.exit(0)

    if action == 'bringforward':
        now = datetime.datetime.now()
        unmanaged = find_unmanaged()
        today = now.strftime("%Y-%m-%d.txt")
        for f in unmanaged:
            bump(f, today)
        sys.exit(0)

    if action == 'tmsa':
        make_symlinks()
        sys.exit(0)