import os
import sys

QGIS_APP = "/Applications/QGIS-LTR.app/Contents"
QGIS_PREFIX = f"{QGIS_APP}/Resources"

# ==== FIX VERY IMPORTANT ====
os.environ["QGIS_PREFIX_PATH"] = QGIS_PREFIX
os.environ["PROJ_LIB"] = f"{QGIS_PREFIX}/proj" 
os.environ["GDAL_DATA"] = f"{QGIS_PREFIX}/gdal"
os.environ["QT_PLUGIN_PATH"] = f"{QGIS_PREFIX}/plugins"
# =============================

os.environ["QT_QPA_PLATFORM"] = "offscreen"

# Python path
sys.path.append(f"{QGIS_PREFIX}/python")
sys.path.append(f"{QGIS_PREFIX}/python/plugins")

from qgis.core import QgsApplication, QgsProviderRegistry
from qgis.analysis import QgsNativeAlgorithms

import processing
from processing.core.Processing import Processing

def start_qgis():
    qgs = QgsApplication([], False)
    qgs.initQgis()

    # === WAJIB: initialize processing ===
    Processing.initialize()
    QgsProviderRegistry.instance()
    qgs.processingRegistry().addProvider(QgsNativeAlgorithms())

    return qgs