""" Captcha.File

Utilities for finding and picking random files from our 'data' directory
"""
#
# PyCAPTCHA Package
# Copyright (C) 2004 Micah Dowty <micah@navi.cx>
#

import os, random, cPickle

# Determine the data directory. This can be overridden after import-time if needed.
dataDir = os.path.join(os.path.split(os.path.abspath(__file__))[0], "data")


class RandomFileFactory(object):
    """Given a list of files and/or directories, this picks a random file.
       Directories are searched for files matching any of a list of extensions.
       Files are relative to our data directory plus a subclass-specified base path.
       """
    extensions = []
    basePath = "."

    def __init__(self, *fileList):
        self.fileList = fileList
        self._fullPaths = None

    def _checkExtension(self, name):
        """Check the file against our given list of extensions"""
        for ext in self.extensions:
            if name.endswith(ext):
                return True
        return False

    def _findFullPaths(self):
        """From our given file list, find a list of full paths to files"""
        paths = []
        for name in self.fileList:
            if name[0] == '/':
                path = name
            else:
                path = os.path.join(dataDir, self.basePath, name)
            if os.path.isdir(path):
                f = open(path + '/filelist.pkl')
                filelist = cPickle.load(f)
                f.close()
                for content in filelist:
                    if self._checkExtension(content):
                        paths.append(os.path.join(path, content))
            else:
                paths.append(path)
        return paths

    def pick(self):
        if self._fullPaths is None:
            self._fullPaths = self._findFullPaths()
        return random.choice(self._fullPaths)

### The End ###