"""
COMMAND-LINE SPECIFIC STUFF
=============================================================================

The rest of the code is specifically for handling the case where Python
Markdown is called from the command line.
"""

from mod_python import apache
markdown = apache.import_module('__init__')

import sys
import logging
from logging import DEBUG, INFO, WARN, ERROR, CRITICAL

EXECUTABLE_NAME_FOR_USAGE = "python markdown.py"
""" The name used in the usage statement displayed for python versions < 2.3.
(With python 2.3 and higher the usage statement is generated by optparse
and uses the actual name of the executable called.) """

OPTPARSE_WARNING = """
Python 2.3 or higher required for advanced command line options.
For lower versions of Python use:

      %s INPUT_FILE > OUTPUT_FILE

""" % EXECUTABLE_NAME_FOR_USAGE

def parse_options():
    """
    Define and parse `optparse` options for command-line usage.
    """

    try:
        optparse = __import__("optparse")
    except:
        if len(sys.argv) == 2:
            return {'input': sys.argv[1],
                    'output': None,
                    'safe': False,
                    'extensions': [],
                    'encoding': None }, CRITICAL
        else:
            print OPTPARSE_WARNING
            return None, None

    parser = optparse.OptionParser(usage="%prog INPUTFILE [options]")
    parser.add_option("-f", "--file", dest="filename", default=sys.stdout,
                      help="write output to OUTPUT_FILE",
                      metavar="OUTPUT_FILE")
    parser.add_option("-e", "--encoding", dest="encoding",
                      help="encoding for input and output files",)
    parser.add_option("-q", "--quiet", default = CRITICAL,
                      action="store_const", const=CRITICAL+10, dest="verbose",
                      help="suppress all messages")
    parser.add_option("-v", "--verbose",
                      action="store_const", const=INFO, dest="verbose",
                      help="print info messages")
    parser.add_option("-s", "--safe", dest="safe", default=False,
                      metavar="SAFE_MODE",
                      help="safe mode ('replace', 'remove' or 'escape'  user's HTML tag)")
    parser.add_option("-o", "--output_format", dest="output_format", 
                      default='xhtml1', metavar="OUTPUT_FORMAT",
                      help="Format of output. One of 'xhtml1' (default) or 'html4'.")
    parser.add_option("--noisy",
                      action="store_const", const=DEBUG, dest="verbose",
                      help="print debug messages")
    parser.add_option("-x", "--extension", action="append", dest="extensions",
                      help = "load extension EXTENSION", metavar="EXTENSION")

    (options, args) = parser.parse_args()

    if not len(args) == 1:
        parser.print_help()
        return None, None
    else:
        input_file = args[0]

    if not options.extensions:
        options.extensions = []

    return {'input': input_file,
            'output': options.filename,
            'safe_mode': options.safe,
            'extensions': options.extensions,
            'encoding': options.encoding,
            'output_format': options.output_format}, options.verbose

def run():
    """Run Markdown from the command line."""

    # Parse options and adjust logging level if necessary
    options, logging_level = parse_options()
    if not options: sys.exit(0)
    if logging_level: logging.getLogger('MARKDOWN').setLevel(logging_level)

    # Run
    markdown.markdownFromFile(**options)