#!/usr/bin/env python3
"""Stop the radio from dropping out of hotspot (modem) mode when the host goes quiet.

Stock behaviour: if the USB host does not talk to the radio for MMDVMHOST_TIMEOUT
(20 s), the firmware calls hotspotExit() and leaves modem mode by itself. That is a
safety net for a crashed host, but it makes the radio unusable as a permanently
attached modem - which is exactly how it is used here.

With the timeout set to 0 the inactivity check is disabled; leaving modem mode is
then only done deliberately (by the user from the radio, or by the host asking the
modem to go idle).
"""
W = "/home/viktor/ogd77rel/uv_src/OpenGD77_MDUV380_DM1701_20260130/MDUV380_firmware/application"
p = W + "/source/functions/hotspot.c"
s = open(p).read()

if "MMDVMHOST_TIMEOUT_DISABLED" in s:
    print("already patched")
    raise SystemExit(0)

old_const = "static const uint32_t MMDVMHOST_TIMEOUT = 20000; // 20s timeout (MMDVMHost mode only, there is no timeout for BlueDV)\n"
assert old_const in s, "timeout constant not found"

new_const = (
    "// 0 disables the host-inactivity timeout, so the radio stays in modem mode until it is\n"
    "// told to leave. Set this back to 20000 to restore the stock 20 second auto-exit.\n"
    "#define MMDVMHOST_TIMEOUT_DISABLED 0\n"
    "static const uint32_t MMDVMHOST_TIMEOUT = MMDVMHOST_TIMEOUT_DISABLED;\n"
)
s = s.replace(old_const, new_const, 1)

# Guard both inactivity checks so a zero timeout means "never time out".
old_check = """				if ((nonVolatileSettings.hotspotType == HOTSPOT_TYPE_MMDVM) &&
						((ticksGetMillis() - mmdvmHostLastActiveTime) > MMDVMHOST_TIMEOUT))
"""
new_check = """				if ((MMDVMHOST_TIMEOUT != 0) && (nonVolatileSettings.hotspotType == HOTSPOT_TYPE_MMDVM) &&
						((ticksGetMillis() - mmdvmHostLastActiveTime) > MMDVMHOST_TIMEOUT))
"""
count = s.count(old_check)
assert count == 2, "expected 2 inactivity checks, found %d" % count
s = s.replace(old_check, new_check)

open(p, "w").write(s)
print("hotspot.c: host-inactivity auto-exit disabled (%d checks guarded)" % count)