#!/usr/bin/env python3

import sys
import signal
import jack


# ============================================================
# Einstellungen
# ============================================================

CLIENT_NAME = "PC-to-CC"
CC_NUMBER = 20

# Program Change -> CC value
PC_MAPPING = {
    0: 1,
    1: 8,
    2: 16,
    3: 24,
    4: 32,
    5: 40,
    6: 48,
    7: 56,
    8: 64,
    9: 72,
    10: 80,
    11: 88,
    12: 96,
    13: 104,
    14: 112,
    15: 128,




}


# ============================================================
# JACK Client erzeugen
# ============================================================

client = jack.Client(CLIENT_NAME)

midi_in = client.midi_inports.register("MIDI-In")
midi_out = client.midi_outports.register("MIDI-Out")


# ============================================================
# MIDI-Verarbeitung
# ============================================================

@client.set_process_callback
def process(frames):

    # JACK MIDI-Ausgabepuffer für diesen Zyklus leeren
    midi_out.clear_buffer()

    # Eingehende MIDI-Events lesen
    for offset, data in midi_in.incoming_midi_events():

        data = bytes(data)

        # Program Change = 0xC0 ... 0xCF
        if len(data) >= 2 and (data[0] & 0xF0) == 0xC0:

            channel = data[0] & 0x0F
            program = data[1]

            # Ist dieser PC gemappt?
            if program not in PC_MAPPING:
                continue

            cc_value = PC_MAPPING[program]

            # Control Change = 0xB0 ... 0xBF
            cc_message = bytes([
                0xB0 | channel,
                CC_NUMBER,
                cc_value
            ])

            midi_out.write_midi_event(
                offset,
                cc_message
            )


# ============================================================
# JACK Shutdown
# ============================================================

@client.set_shutdown_callback
def shutdown(status, reason):
    print()
    print("JACK wurde beendet.")
    sys.exit(0)


# ============================================================
# Start
# ============================================================

print()
print("================================")
print(" PC-to-CC")
print("================================")
print()

print()
print("JACK Client:")
print("  PC-to-CC")
print()
print("MIDI Ports:")
print("  PC-to-CC:MIDI-In")
print("  PC-to-CC:MIDI-Out")
print()
print("Ctrl+C zum Beenden.")
print()

try:
    client.activate()

except jack.JackError as e:
    print("Fehler beim Starten von JACK:")
    print(e)
    sys.exit(1)


try:
    signal.pause()

except KeyboardInterrupt:
    print()
    print("Beende PC-to-CC ...")

finally:
    client.deactivate()
    client.close()