#!/usr/bin/python2

##  ./wavmerge.py in1.wav in2.wav in3.wav outfile.wav

import wave
import sys
import os

def main():
    files = sys.argv[1:]

    firstfile = files.pop(0)
    ff = wave.open(firstfile, 'r')
    params = ff.getparams()
    (nchannels, sampwidth, framerate, nframes, comptype, compname) = params
    checkparams = (nchannels, sampwidth, framerate, comptype, compname)
    data = ff.readframes(nframes)
    ff.close()
    
    newfile = files.pop()
    if os.path.exists(newfile):
        sys.stderr.write('ERROR: output file exists: %s\n' % newfile)
    nf = wave.open(newfile, 'w')
    nf.setparams(params) # this ALSO sets nframes
    nf.writeframesraw(data)

    for file in files:
        f = wave.open(file, 'r')
        fparams = f.getparams()
        (nchannels, sampwidth, framerate, nframes, comptype, compname) = fparams
        cparams = (nchannels, sampwidth, framerate, comptype, compname)
        if not cparams == checkparams:
            f = 'WARNING: file parameters differ\n   %20s: %s\n  %20s:%s\n'
            sys.stderr.write(f % (firstfile, checkparams, file, cparams))
        data = f.readframes(nframes)
        nf.writeframesraw(data)
        f.close()

    nf.close()  # this corrects nframes

if __name__ == '__main__':
    main()