# cmdlet.py
# Copyright (C) 2008 Michael Foord
# E-mail: fuzzyman AT voidspace DOT org DOT uk

import os
import System

__version__ = '0.1.0'

__all__ = ['Action', 'Cmdlet', 'ignored', 'listdir', 'notolderthan', 'prettyprint']

ignored = object()

class Cmdlet(list):
    def __init__(self, function, _populated=False):
        self.function = function
        self._populated = _populated
        
    def __call__(self, *args, **keywargs):
        return Cmdlet(self.function(*args, **keywargs))
    

    def __rshift__(self, other):
        data = self
        if not self._populated:
            # TODO: the first function must return a list ?
            data = self.function()

        new = Cmdlet(other.function, True)
        vals = [other.function(m) for m in data]
        new[:] = [v for v in vals if v is not ignored]
        return new
    
    
    def __rrshift__(self, other):
        new = Cmdlet(self.function, True)
        vals = [self.function(m) for m in other]
        new[:] = [v for v in vals if v is not ignored]
        return new
        
    
    def __repr__(self):
        return 'Cmdlet(%s)' % list.__repr__(self)
    

class Action(Cmdlet):
    def __rshift__(self, other):
        Cmdlet.__rshift__(self, other)
        return None
        
    def __repr__(self):
        return 'Action(%s)' % self.function.__name__
    

class Path(object):
    def __init__(self, path, entry):
        self.dir = path
        self.name = entry
        self.path = os.path.join(path, entry)
        self.mtime = System.IO.File.GetCreationTime(self.path)
        self.ctime = System.IO.File.GetLastWriteTime(self.path)
        
    def __repr__(self):
        start = 'File:'
        if os.path.isdir(self.path):
            start = 'Dir:'
        ctime = self.ctime
        mtime = self.mtime
        return "%s %s :ctime: %s :mtime: %s" % (start, self.path, ctime, mtime)
            

    
def f_listdir(path):
    def listdir():
        return [Path(path, member) for member in os.listdir(path)]
    return listdir


def f_notolderthan(date):
    datetime = System.DateTime.Parse(date)
    def notolderthan(member):
        if member.mtime >= datetime:
            return member
        return  ignored
    return notolderthan


def f_prettyprint(val):
    print val
f_prettyprint.__name__ = 'prettyprint'


listdir = Cmdlet(f_listdir)
notolderthan = Cmdlet(f_notolderthan)
prettyprint = Action(f_prettyprint)



if __name__ == '__main__':
    # Prints all the paths in the current directory younger than the third of February
    print 'First test'
    listdir('.') >> notolderthan('2/3/08') >> prettyprint

    def recursive_walk(path):
        for e in os.listdir(path):
            p = os.path.join(path, e)
            if os.path.isfile(p):
                yield Path(path, e)
            else:
                for entry in recursive_walk(p):
                    yield entry
    
    print
    print 'Passing in a generator'
    recursive_walk('.')  >> notolderthan('2/3/08') >> prettyprint