#!/usr/bin/env python2.7
# -*- coding: utf-8 -*-

import sys
import re
import os, errno
import time
import argparse
import subprocess
from pprint import pprint

def mkdir_p(path):
    try:
        os.makedirs(path)
    except OSError as exc:
        if exc.errno != errno.EEXIST:
            raise


def Midi2Mp3(in_file, out_file, **kwargs):
    verbose = kwargs.get('verbose', 0)
    force = kwargs.get('force', 0)
    dry_run = kwargs.get('dry_run', False)

    timid_cmd = "timidity -Ow -o -"
    lame_cmd = "lame - "
    out_dir = os.path.dirname(out_file)

    if not os.path.exists(out_dir):
        if verbose > 2:
            print "Creating %s" % out_dir
        if not dry_run:
            mkdir_p(out_dir)

    if not force:
        if (os.path.exists(out_file) and os.path.getmtime(out_file) > os.path.getmtime(in_file)):
            if verbose > 1:
                print "%s is up to date" % out_file
            return False

    cmd = "%s %s | %s %s" % (timid_cmd, in_file, lame_cmd, out_file)
    if dry_run:
        print cmd
    else:
        if verbose:
            print cmd
        out = subprocess.check_output(cmd, shell=True)
    return True
# Midi2Mp3

def RebuildMp3s(**kwargs):
    directories = kwargs.get('directories', 0)
    out_root = kwargs.get('output_directory', 0)
    errors = kwargs.get('errors', 0)
    prune = kwargs.get('prune', 0)
    verbose = kwargs.get('verbose', 0)
    count = kwargs.get('count', 0)
    nice = kwargs.get('nice', 0)
    dry_run = kwargs.get('dry_run', False)

    nice_count = 0
    for dir_start in directories:
        if dir_start.endswith('/'):
            dir_start = dir_start[:-1] # having a trailing / screws up os.path.dirname
        parent_dir_start = os.path.dirname(dir_start)
            
        for root, dirs, files in os.walk(dir_start):
            #print root, dirs, files; continue
            base = os.path.basename(root)

            if verbose > 1:
                print "Entering:", root

            # look for any .mid files
            for f in files:
                if f.endswith('.mid'):
                    nice_count += 1

                    in_file = os.path.join(root, f)

                    if out_root == dir_start:
                        out_file = in_file  # extension gets changed below
                    elif prune:
                        tmp = re.sub('^'+parent_dir_start+'/', '', in_file)
                        out_file = os.path.join(out_root, tmp)
                    else:
                        out_file = os.path.join(out_root, root, f)
                    out_file = re.sub('/midi/', '/mp3/', out_file)
                    out_file = re.sub('\.mid$', '.mp3', out_file)

                    if Midi2Mp3(in_file, out_file, **kwargs):
                        count -= 1
                        if count < 0:
                            break

                        # This sucker can eat Manhattan, so we pause every once in a while
                        nice_count += 1
                        if nice_count % nice == 0:
                            if verbose:
                                print >>sys.stderr, "Pausing ..."
                            time.sleep(1)
            # for each file in the directory
        # end os.walk()

    # end for all directories
# RebuildMp3s

if __name__ == "__main__":

    parser = argparse.ArgumentParser(description='walk directory tree and convert .mid to .mp3 as necessary')
    parser.add_argument('directories', metavar='file', nargs="+",
                        help="one or more directories containing .mid files.")
    parser.add_argument('output_directory', nargs="?",
                        help="directory to put resulting MP3s into. Created if necessary.")
    parser.add_argument('--nice', type=int, default=10000,
                       help='sleep for 1 second after every N [10000] files.')
    parser.add_argument('--count', '-c', type=int, default=(2**30),
                       help='number of files to process. default: all')
    parser.add_argument('-e', '--errors', dest='errors', default=False, action="store_true",
                       help='print errors on exit.')
    parser.add_argument('-f', dest='force_rebuild', default=False, action="store_true",
                       help='force rebuilding of everything.')
    parser.add_argument('-p', dest='prune', default=False, action='store_true', 
                        help='prune output directory name to basename of each input directory.')
    parser.add_argument('-v', dest='verbose', default=0,
                       action='count', help='print verbose debugging information.')
    parser.add_argument('-n', dest='dry_run', default=False, action='store_true',
                       help="dry run -- don't actually do anything.")

    args = vars(parser.parse_args())
    if not args['output_directory']:
        args['output_directory'] = args['directories'][-1]
        if len(args['directories']) > 1:
            args['directories'] = args['directories'][:-1]

    #print args; 1/0
    RebuildMp3s(**args)