# pylint: disable=E0602
Import("env")  # noqa

import os

# Filter out waveform/PWM code from the Arduino core build
# This saves ~596 bytes of RAM and 464 bytes of flash by not
# instantiating the waveform generator state structures (wvfState + pwmState).
#
# The waveform code is used by: analogWrite, Tone, Servo, and direct
# startWaveform/stopWaveform calls. ESPHome's esp8266_pwm component
# calls require_waveform() to keep this code when needed.
#
# When excluded, we provide stub implementations of stopWaveform() and
# _stopPWM() since digitalWrite() calls these unconditionally.


def has_define_flag(env, name):
    """Check if a define exists in the build flags."""
    define_flag = f"-D{name}"
    # Check BUILD_FLAGS (where ESPHome puts its defines)
    for flag in env.get("BUILD_FLAGS", []):
        if flag == define_flag or flag.startswith(f"{define_flag}="):
            return True
    # Also check CPPDEFINES list (parsed defines)
    for define in env.get("CPPDEFINES", []):
        if isinstance(define, tuple):
            if define[0] == name:
                return True
        elif define == name:
            return True
    return False

# USE_ESP8266_WAVEFORM_STUBS is defined when no component needs waveform
if has_define_flag(env, "USE_ESP8266_WAVEFORM_STUBS"):

    def filter_waveform_from_core(env, node):
        """Filter callback to exclude waveform files from framework build."""
        path = node.get_path()
        filename = os.path.basename(path)
        if filename in (
            "core_esp8266_waveform_pwm.cpp",
            "core_esp8266_waveform_phase.cpp",
        ):
            print(f"ESPHome: Excluding {filename} from build (waveform not required)")
            return None
        return node

    # Apply the filter to framework sources
    env.AddBuildMiddleware(filter_waveform_from_core, "**/cores/esp8266/*.cpp")