#!/usr/bin/env python3

# based on the cvtsample.py included in the GBDK example:
# https://github.com/gbdk-2020/gbdk-2020/blob/develop/gbdk-lib/examples/gb/wav_sample/utils/cvtsample.py

import sys
import wave
import os

sGBDK = """//AUTOGENERATED FILE FROM cvtsample
#include <stdint.h>
#include <gbdk/platform.h>
BANKREF({:s})
"""

hGBDK = """//AUTOGENERATED FILE FROM cvtsample
#ifndef WAVE_SOUND_{:s}_H
#define WAVE_SOUND_{:s}_H
#include <stdint.h>
#include <gbdk/platform.h>

#define {:s}_SIZE 0x{:x}
extern const uint8_t {:s}[];

BANKREF_EXTERN({:s})
#endif
"""

def main(argv=None):
    argv = argv or sys.argv
    if len(argv) < 2:
        sys.stderr.write("cvtsample.py: no filename; try cvtsample.py --help\n")
        sys.exit(1)

    infilename = argv[1]
    ident = argv[2] if len(argv) > 2 else None
    fmt = argv[3].upper() if len(argv) > 3 else "C"
    outdir = argv[4] if len(argv) > 4 else os.getcwd()

    if infilename in ('--help', '-h'):
        print("usage: cvtsample.py SOURCE [IDENTIFIER] [FMT] [OUTDIR]")
        return

    if ident == "(None)":
        ident = None
    if ident == None:
        ident = os.path.splitext(os.path.basename(infilename))[0]

    if fmt == "C":
        sHDR = "const UINT8 {:s}[] = {{\n"
        sFOOT = "};\n"
        sEMIT = "0x{:x}"
        sNEW = ",\n"
        sNONEW = ","
    elif fmt == "GBDK":
        outheader = os.path.join(outdir, f"{ident}.h")
        outsource = os.path.join(outdir, f"{ident}.c")
        sHDR = "const uint8_t {:s}[] = {{\n"
        sFOOT = "};\n"
        sEMIT = "0x{:x}"
        sNEW = ",\n"
        sNONEW = ","
    elif fmt == "ASM":
        sHDR = "{:s}::"
        sFOOT = ""
        sEMIT = "${:x}"
        sNEW = "\n"
        sNONEW = ","

    with wave.open(infilename, mode="rb") as f:
        p = f.getparams()        
        if (p.nchannels == 1) and (p.sampwidth == 1) and (p.framerate >= 8000) and (p.framerate <= 8192) and (p.comptype == 'NONE'):
            data = f.readframes(p.nframes)
            c = 0
            cnt = 0;
            flag = False

            s = sHDR.format(ident)
            for i in range(len(data) - len(data) % 32):
                c = ((c << 4) | (data[i] >> 4)) & 0xFF
                if flag:
                    s += sEMIT.format(c)
                    cnt += 1
                    s += sNEW if (cnt % 16 == 0) else sNONEW
                        
                flag = not flag
            s += sFOOT

            if fmt == "GBDK":
                with open(outsource, "w") as o:
                    o.write(sGBDK.format(ident))
                    o.write(s)
                with open(outheader, "w") as o:
                    o.write(hGBDK.format(ident, ident, ident, cnt, ident, ident))
            else:
                sys.stdout.write(s)
                sys.stdout.flush()
        else:
            sys.stderr.write("ERROR: Invalid wav file format\n")
            sys.stderr.write("Requires - nChannels: 1, sampWidth: 1, rate: 8000 - 8192, compType: NONE\n")
            sys.stderr.write("Found    - nChannels: %d, sampWidth: %d, rate: %d, compType: %s\n" % (p.nchannels, p.sampwidth, p.framerate, p.comptype))
            sys.stderr.flush()

if __name__=='__main__':
    main()