# todosfromfile.py
# By Matthew Dixon Cowles, matt@mondoinfo.com
#
# Provided with no warranty.
# Distributable under the GNU GPL.
# Requires Python 2.7 but only because I used the argparse module.
# The appscript module is at: http://appscript.sourceforge.net/
#
# Version 1.1
# September 6, 2010
# Removed some unnecessary machinery
#
# Version 1.0
# August 29, 2010
#
# Adds to-dos to the program Things by Cultured Code according to
# a text file of templates and its command-line arguments.
#
# Expects its template text file to have two sorts of lines.
# "Time-before" lines and to-do item lines. It should look like:
#
# 1 Month
# A to-do
#
# 2 Weeks
# Another to-do
# A third
#
# 4 Days
# Another
#
# On Day
# Another
#
# Blank lines and lines begging with a "#" are ignored.
#
# Command-line options are: template file name (--file), event name
# (--name), and event date (--date, format YYYY-MM-DD). The program
# creates a Things project with the name of the event and adds
# to-dos to the project with the text from the template file and a
# due date that's as far in advance of the date specified on the
# command-line as the previous time-before line in the file
# specified.


import appscript as aps
import argparse
import datetime

    
def isInt(s):
  try:
    dummy=int(s)
  except ValueError:
    return False
  else:
    return True
    
def getArgs():
  parser=argparse.ArgumentParser()
  parser.add_argument("--file",required=True,action="store")
  parser.add_argument("--name",required=True,action="store")
  parser.add_argument("--date",required=True,action="store")
  args=parser.parse_args()
  try:
    date=datetime.datetime.strptime(args.date,"%Y-%m-%d")
  except ValueError:
    print "Date must be in format YYYY-MM-DD"
    raise SystemExit
  # strptime() gives us unnecessary time values
  eventDate=datetime.date(date.year,date.month,date.day)
  return args.file,args.name,eventDate
  
def getTemplates(filename):
  items=[]
  timeBefore=None
  timeBeforeUsed=True
  for line in file(filename):
    line=line.rstrip()
    if line=="" or line.startswith("#"):
      continue
      
    s=line.lower().split()
  
    # We don't care about "month" vs "months"
    if len(s)==2 and s[1].endswith("s"):
      s[1]=s[1][:-1]
    
    if len(s)==2 and ((isInt(s[0]) and s[1] in ("day","week","month")) \
      or (s[0]=="on" and s[1]=="day")):
      # We have a "time before" line
      if not timeBeforeUsed:
        print line,"Comes after another time-before line that wasn't used"
        raise SystemExit
      timeBeforeUsed=False
      if s[0]=="on" and s[1]=="day":
        timeBefore={"days": 0, "weeks": 0, "months": 0}
      elif s[1]=="month":
        timeBefore={"days": 0, "weeks": 0, "months": int(s[0])}
      elif s[1]=="week":
        timeBefore={"days": 0, "weeks": int(s[0]), "months": 0}
      elif s[1]=="day":
        timeBefore={"days": int(s[0]), "weeks": 0, "months": 0}
      else:
        assert 1==0,"Can't happen"

    else:
      # We have a to-do
      if timeBefore==None:
        print "To-do before any time-before lines"
        raise SystemExit
      timeBeforeUsed=True
      items.append({"text": line, "time before": timeBefore})
  return items
  
def subtractDate(date,timeBefore):
  if timeBefore["days"]==0 and timeBefore["weeks"]==0 and timeBefore["months"]==0:
    return date
  if timeBefore["days"]!=0:
    return date-datetime.timedelta(days=timeBefore["days"])
  elif timeBefore["weeks"]!=0:
    return date-datetime.timedelta(weeks=timeBefore["weeks"])
  elif timeBefore["months"]!=0:
    y=date.year
    m=date.month-timeBefore["months"]
    if m<=0:
      m+=12
      y-=1
      
    # What's October 31 minus 1 month? For our purposes here, it's September 30.
    daysMinus=0
    while True:
      try:
       earlier=datetime.date(year=y,month=m,day=date.day-daysMinus)
      except ValueError:
        daysMinus+=1
        assert daysMinus<=3
      else:
        return earlier
  else:
    assert 1==0, "Can't happen"
  
def main():
  templateFile,eventTitle,eventDate=getArgs()
  templates=getTemplates(templateFile)

  thingsApp=aps.app("Things")

  proj=thingsApp.make(new=aps.k.project,with_properties={aps.k.name: 
    eventTitle,aps.k.due_date: eventDate})

  for template in templates:
    dueDate=subtractDate(eventDate,template["time before"])
    print template["text"],dueDate
    todo=proj.make(new=aps.k.to_do,with_properties={aps.k.name:
      template["text"],aps.k.due_date:dueDate})

  return None
  
if __name__=="__main__":
  main()