"""
Find raw sodar data files in need of processing.

Files are presumed organized according to NCCOOS conventions.
"""

import os

def findMissing(source, destination):
    """
    Find raw sodar data files in need of processing.

    Get source filetree.
    Get destination file tree.
    Construct ideal destination file tree from source
    Compare ideal destination file tree to destination file tree
    Construct difference file tree as list of tuples (source, destination)
    """
    
    sourceWalk = os.walk(source)
    sourceWalk = [(fullPath, subDirs, files)
                 for fullPath, subDirs, files
                 in sourceWalk]
    sourceWalk = sourceWalk[1:]
    
    destinationWalk = os.walk(destination)
    destinationWalk = [(fullPath, subDirs, files)
                       for fullPath, subDirs, files
                       in destinationWalk]
    destinationWalk = destinationWalk[1:]
    destinationWalk = [fullPath
                       for fullPath, subDirs, files
                       in destinationWalk
                       if not subDirs]
    # always mark most recent destination as missing
    # to keep it updated as source is updated during the day
    destinationWalk = sorted(destinationWalk)
    destinationWalk = destinationWalk[:-1]
    
    idealWalk = [os.path.join(destination,
                              fullPath.replace(source + os.path.sep, ''),
                              fileName.replace('.dat', ''))
                          
                 for fullPath, subDirs, files in sourceWalk
                 for fileName in files]
    
    differenceWalk = [path
                      for path
                      in idealWalk
                      if path not in destinationWalk]
    
    differenceWalk = sorted(differenceWalk)
    
    differenceWalk = [(os.path.join(source,
                                    path.replace(destination + os.path.sep,
                                                 '') + '.dat'),
                       path)
                       for path
                       in differenceWalk]
    
    return differenceWalk

if __name__ == '__main__':
    import optparse
    from pprint import pprint
    
    parser = optparse.OptionParser()
    (values, args) = parser.parse_args()
    (source, destination) = tuple(args)
    if source[-1] == os.path.sep:
        source = source[:-1]
    if destination[-1] == os.path.sep:
        destination = destination[:-1]
    
    pprint(findMissing(source, destination))