Multishot

#!/usr/bin/python3

'''Takes a series of numbered screenshots.

NAME
  multishot

SYNOPSIS
  multishot [-h] [-d DIR] [-f FMT] [-q] [-v] [-V] num-screenshots

DESCRIPTION
  This script saves a number of screenshots in quick succession, which is
  handy for quickly saving a series of screenshots of a Facebook thread to
  be stitched together using the stitch script. The external commands scrot
  and bell are used to record each screenshot and prompt the user to advance
  the screen by one page. The filenames are indicated by means of a C format
  string. The defult format string is "%02d.png" so that the image filenames
  are 01.png, 02.png, 03.png and so on.

Author:
  Daniel Neville (Blancmange), creamygoat@gmail.com

Copyright:
  None

Licence:
  Public domain


INDEX


Imports

Constants

Exceptions:

  Error
  ArgError
  FileError
  CmdError

Main:

  Main()

'''


#-------------------------------------------------------------------------------
# Imports
#-------------------------------------------------------------------------------


import sys
import traceback
import os
import time
import re
import argparse


#-------------------------------------------------------------------------------
# Constants
#-------------------------------------------------------------------------------


VersionStr = '1.0.0.0'


#-------------------------------------------------------------------------------
# Exceptions
#-------------------------------------------------------------------------------


class Error (Exception):
  pass

class ArgError (Error):
  pass

class FileError(Error):
  pass

class CmdError(Error):
  pass


#-------------------------------------------------------------------------------
# Main
#-------------------------------------------------------------------------------


def Main():

  #-----------------------------------------------------------------------------

  def CheckArgRange(Name, Value, MinValue, MaxValue):
    if not MinValue <= Value <= MaxValue:
      raise ArgError('argument ' + Name + ': out of range ' + #<<<<<<<<<
          str(MinValue) + '..' + str(MaxValue) +'.')

  #-----------------------------------------------------------------------------

  def GetArguments():

    cn = os.path.basename(sys.argv[0])

    Parser = argparse.ArgumentParser(
      prog=cn,
      add_help=False,
      description='Saves a series of numbered screenshots.'
    )

    Parser.add_argument(
        '-h', '--help',
        dest='Help', action='store_true',
        help='Display this message and exit.')
    Parser.add_argument(
        '-d', '--dir', metavar='DIR',
        dest='Dir', default='',
        help=('Specify the directory where the screenshot image files are ' +
            'to be saved. The default is the current directory.'))
    Parser.add_argument(
        '-f', '--name-format', metavar='FMT',
        dest='NameFormat', default='%02d.png',
        help=('Specify the C format string for the numbered image ' +
            'file names (starting at 1). The default is "%%02d.png".'))
    Parser.add_argument(
        '-q', '--quiet',
        dest='Quiet', action='store_true',
        help='Suppress all output.')
    Parser.add_argument(
        '-v', '--verbose',
        dest='Verbose', action='store_true',
        help='Display detailed progress information.')
    Parser.add_argument(
        '-V', '--version',
        dest='Version', action='store_true',
        help='Display version and exit.')
    Parser.add_argument(
        'NumScreenshots', metavar='num-screenshots',
        type=int,
        help=('Specify the number of screenshot files to load. If the ' +
            'default format string is used, the files will be named ' +
            '01.png, 02.png, 03.png and so on.'))

    if '-h' in sys.argv or '--help' in sys.argv:
      Parser.print_help()
      print (
        '\nExamples:\n' +
        '  ' + cn + ' 29\n' +
        '  ' + cn + ' -d shots/ -f "Screenshot_%03d.png" 110'
      )
      sys.exit(0)

    if '-V' in sys.argv or '--version' in sys.argv:
      print(VersionStr)
      sys.exit(0)

    Args = Parser.parse_args()

    if Args.Version:
      print(VersionStr)
      sys.exit(0)

    setattr(Args, 'Verbosity', 0 if Args.Quiet else (2 if Args.Verbose else 1))

    CheckArgRange('num-screenshots', Args.NumScreenshots, 1, 999)

    try:
      S = Args.NameFormat % (1)
    except (TypeError, ValueError):
      raise ArgError('argument -f/--name-format: Invalid format string.')

    return Args

  #-----------------------------------------------------------------------------

  Result = 0
  ErrMsg = ''

  CmdName = os.path.basename(sys.argv[0])

  try:

    Args = GetArguments()

    Verbosity = Args.Verbosity

    n = Args.NumScreenshots

    if Verbosity >= 1:
      print('Get ready to save ' + str(n) + ' screenshots.')
    time.sleep(5)

    for i in range(1, n + 1):

      ImgFileName =  os.path.join(Args.Dir, Args.NameFormat % (i))

      CLIImgFileName = re.sub(r'"', r'\"', ImgFileName)
      if ' ' in CLIImgFileName or "'" in CLIImgFileName:
        CLIImgFileName = '"' + CLIImgFileName + '"'

      Result = os.system('scrot ' + CLIImgFileName)

      if Result != 0:
        raise CmdError('scrot failed with error code ' + str(Result) + '.')

      if Verbosity >= 2:
        print('Saved: ' + CLIImgFileName)

      os.system('qbell')

      if i < n:
        time.sleep(0.500)

    if Verbosity >= 2:
      print('Done!')

  except (ArgError) as E:

    ErrMsg = 'error: ' + str(E)
    Result = 2

  except (FileError) as E:

    ErrMsg = str(E)
    Result = 3

  except (CmdError) as E:

    ErrMsg = str(E)
    Result = 4

  except (Exception) as E:

    exc_type, exc_value, exc_traceback = sys.exc_info()
    ErrLines = traceback.format_exc().splitlines()
    ErrMsg = 'Unhandled exception:\n' + '\n'.join(ErrLines)
    Result = 1

  if ErrMsg != '':
    print(CmdName + ': ' + ErrMsg, file=sys.stderr)

  return Result


#-------------------------------------------------------------------------------
# Command line trigger
#-------------------------------------------------------------------------------


if __name__ == '__main__':
  sys.exit(Main())


#-------------------------------------------------------------------------------