src/servers/soil.py

"""
Soil Properties Server using Google Earth Engine
"""

import ee
import os
import json
from typing import Dict, Any


class SoilPropertiesServer:
    """Google Earth Engine Soil Server"""
    
    def __init__(self):
        self._initialize_gee()
        
        self.layers = {
            "clay": "OpenLandMap/SOL/SOL_CLAY-WFRACTION_USDA-3A1A1A_M/v02",
            "sand": "OpenLandMap/SOL/SOL_SAND-WFRACTION_USDA-3A1A1A_M/v02",
            "phh2o": "OpenLandMap/SOL/SOL_PH-H2O_USDA-4C1A2A_M/v02",
            "soc": "OpenLandMap/SOL/SOL_ORGANIC-CARBON_USDA-6A1C_M/v02"
        }
        self.depth_band = "b0"
    
    def _initialize_gee(self):
        """Initialize GEE with service account"""
        try:
            # Check if service account key is provided
            service_account_key = os.environ.get('GEE_SERVICE_ACCOUNT_KEY')
            
            if service_account_key:
                # Parse JSON key
                credentials_dict = json.loads(service_account_key)
                credentials = ee.ServiceAccountCredentials(
                    credentials_dict['client_email'],
                    key_data=service_account_key
                )
                ee.Initialize(credentials)
                print("✅ GEE initialized with service account")
            else:
                # Fallback to default credentials (for local development)
                ee.Initialize(project='MCPprototypeGEE')
                print("✅ GEE initialized with default credentials")
                
        except Exception as e:
            print(f"⚠️ GEE initialization failed: {str(e)}")
            raise
    
    async def get_data(self, lat: float, lon: float) -> Dict[str, Any]:
        """Get soil properties at coordinate"""
        try:
            point = ee.Geometry.Point([lon, lat])
            results = {}
            
            for prop_name, image_id in self.layers.items():
                try:
                    image = ee.Image(image_id).select(self.depth_band)
                    value = image.sample(point, 250).first().get(self.depth_band).getInfo()
                    
                    if value is not None:
                        if prop_name in ['clay', 'sand']:
                            results[prop_name] = round(value / 10, 1)
                        elif prop_name == 'phh2o':
                            results[prop_name] = round(value / 10, 1)
                        elif prop_name == 'soc':
                            results[prop_name] = round(value / 10, 1)
                    else:
                        results[prop_name] = None
                except:
                    results[prop_name] = None
            
            if not any(v is not None for v in results.values()):
                return {
                    "status": "error",
                    "error": "No soil data available"
                }
            
            silt = None
            if results.get("clay") and results.get("sand"):
                silt = round(100 - results["clay"] - results["sand"], 1)
            
            return {
                "status": "success",
                "data": {
                    "clay_percent": results.get("clay"),
                    "sand_percent": results.get("sand"),
                    "silt_percent": silt,
                    "pH": results.get("phh2o"),
                    "organic_carbon_g_kg": results.get("soc"),
                    "data_source": "Google Earth Engine (OpenLandMap)",
                    "location": {"latitude": lat, "longitude": lon},
                    "depth": "0-5cm"
                }
            }
            
        except Exception as e:
            return {
                "status": "error",
                "error": str(e)
            }