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

from fcntl import fcntl, F_GETFL, F_SETFL
from os import O_NONBLOCK, read
import subprocess
import argparse
from commands import getoutput

def channel_number(c):
    try:
        c = int(c)
    except:
        raise argparse.ArgumentTypeError('Channel number must be an integer')
    if c < 0:
        raise argparse.ArgumentTypeError('Please specify a channel number greater than 0')
    return c

def delay_var(d):
    try:
        d = int(d)
    except:
        raise argparse.ArgumentTypeError('Delay interval must be an integer')
    if d < 100:
        d = 100
    return d

parser = argparse.ArgumentParser()
parser.add_argument('-d', '--delay', metavar='N', type=delay_var, default=100, help='Delay interval in milliseconds')
parser.add_argument('-s', '--scale', type=int, help='use dB scale; output range 0-<SCALE> (integer); if not specified, output range is linear [0..1]')
parser.add_argument('-f', '--file', help='Output file')
parser.add_argument('-c', '--channels', metavar='C', type=int, help='Channel number', default=1)
parser.add_argument('ports', nargs='*')

args = parser.parse_args()

delay = args.delay
if not args.channels and not args.ports:
    print 'At least a channel value or output port must be specified'
    parser.print_help()
    exit()
elif args.ports:
    jack_port_list = []
    port_iter = iter(getoutput('jack_lsp -p').split('\n'))
    while True:
        try:
            port = port_iter.next().strip()
            props = port_iter.next().strip().replace('properties: ', '').rstrip(',').split(',')
            if not 'output' in props:
                continue
            jack_port_list.append(port)
        except:
            break
    not_valid = []
    not_found = []
    for port in args.ports:
        if not ':' in port:
            not_valid.append(port)
            continue
        if not port in jack_port_list:
            not_found.append(port)
    if not_valid:
        print 'The following specified port names are not valid (the ports will still be created, you have to connect them manually:'
        print '\n'.join(['- {}'.format(p) for p in not_valid])
    if not_found:
        print 'The following ports are not available (thus will not be connected, do it manually):'
        print '\n'.join(['- {}'.format(p) for p in not_found])
    ports = ' '.join(args.ports)
else:
    ports = ' '.join(['input_{}'.format(i + 1) for i in xrange(args.channels)])

cmd = './jack-peak -q {scale} -d {delay} {ports}'.format(scale='-i {}'.format(args.scale) if args.scale else '', delay=delay, ports=ports)
proc = subprocess.Popen(cmd.split(),
                        stdout=subprocess.PIPE, 
                        )
flags = fcntl(proc.stdout, F_GETFL)
fcntl(proc.stdout, F_SETFL, flags | O_NONBLOCK)

empty = 0
while True:
    try:
        output = read(proc.stdout.fileno(), 1024)
        if output:
            if args.file:
                with open(args.file, 'a') as output_file:
                    output_file.write(output)
                    output_file.write('\n')
            else:
                print output
        else:
            break
    except KeyboardInterrupt:
        proc.terminate()
        break
    except OSError:
        pass
    except:
        break