"""
CropAI Physics-Informed Disease Micro-Climate Twin (Bio-Twin™)
Computes Leaf Wetness Duration (LWD), Dew-Point Differential, and Spore Germination Index (SGI)
to forecast fungal infection windows before spore penetration occurs.
"""

import math
from typing import Dict, Any, List


class PhysicsBioTwinEngine:
    """Physics-Informed Neural & Thermodynamic Fungal Infection Predictor."""

    @staticmethod
    def calculate_dew_point(temp_c: float, humidity_pct: float) -> float:
        """Calculates dew point using the Magnus-Tetens formula."""
        a = 17.27
        b = 237.7
        alpha = ((a * temp_c) / (b + temp_c)) + math.log(max(humidity_pct, 1.0) / 100.0)
        dew_point = (b * alpha) / (a - alpha)
        return round(dew_point, 2)

    @staticmethod
    def simulate_microclimate_infection_risk(
        crop: str,
        temperature_c: float,
        humidity_pct: float,
        wind_speed_kmh: float,
        leaf_wetness_hours: float,
        cloud_cover_pct: float = 60.0
    ) -> Dict[str, Any]:
        """
        Simulates micro-climate conditions inside the crop canopy and computes
        the Spore Germination Index (SGI: 0.0 to 1.0) for high-risk pathogens.
        """
        dew_point = PhysicsBioTwinEngine.calculate_dew_point(temperature_c, humidity_pct)
        temp_dew_diff = max(0.0, temperature_c - dew_point)

        # 1. Estimate effective Leaf Wetness Duration (LWD)
        # Higher humidity + low wind + low temp-dew difference = high condensation retention
        wind_factor = max(0.2, 1.0 - (wind_speed_kmh / 40.0))
        humidity_factor = max(0.0, (humidity_pct - 65.0) / 35.0)
        
        effective_lwd = leaf_wetness_hours + (humidity_factor * wind_factor * 3.5)
        effective_lwd = min(24.0, max(0.0, effective_lwd))

        # 2. Pathogen Specific Fungal Infection Models
        crop_lower = crop.lower()
        if "rice" in crop_lower or "paddy" in crop_lower:
            target_disease = "Paddy Blast (Magnaporthe oryzae)"
            # Blast optimal: Temp 24-28C, LWD > 8 hrs, Humidity > 85%
            temp_suitability = math.exp(-0.5 * ((temperature_c - 26.0) / 4.0) ** 2)
            lwd_suitability = 1.0 / (1.0 + math.exp(-0.8 * (effective_lwd - 7.0)))
            hum_suitability = 1.0 / (1.0 + math.exp(-0.2 * (humidity_pct - 82.0)))
            sgi = temp_suitability * lwd_suitability * hum_suitability
            critical_window_hours = 18

        elif "wheat" in crop_lower:
            target_disease = "Yellow / Stripe Rust (Puccinia striiformis)"
            # Rust optimal: Temp 12-18C, high moisture, low wind
            temp_suitability = math.exp(-0.5 * ((temperature_c - 15.0) / 3.5) ** 2)
            lwd_suitability = 1.0 / (1.0 + math.exp(-0.7 * (effective_lwd - 6.0)))
            hum_suitability = 1.0 / (1.0 + math.exp(-0.15 * (humidity_pct - 80.0)))
            sgi = temp_suitability * lwd_suitability * hum_suitability
            critical_window_hours = 24

        elif "potato" in crop_lower or "tomato" in crop_lower:
            target_disease = "Late Blight (Phytophthora infestans)"
            # Late Blight optimal: Temp 15-22C, LWD > 10 hrs
            temp_suitability = math.exp(-0.5 * ((temperature_c - 18.0) / 3.0) ** 2)
            lwd_suitability = 1.0 / (1.0 + math.exp(-0.9 * (effective_lwd - 8.0)))
            hum_suitability = 1.0 / (1.0 + math.exp(-0.2 * (humidity_pct - 85.0)))
            sgi = temp_suitability * lwd_suitability * hum_suitability
            critical_window_hours = 12

        else:
            target_disease = "General Fungal Leaf Spot / Blight"
            sgi = (humidity_pct / 100.0) * min(1.0, effective_lwd / 12.0)
            critical_window_hours = 24

        sgi = min(1.0, max(0.05, sgi))
        sgi_pct = round(sgi * 100.0, 1)

        # 3. Categorize Risk & Action Protocol
        if sgi >= 0.70:
            risk_category = "CRITICAL_SPORE_GERMINATION_ALERT"
            forecast_message = (
                f"High-risk fungal germination window active for {target_disease}. "
                f"Leaf canopy wetness ({round(effective_lwd, 1)} hrs) and thermal conditions "
                f"are optimal for spore hyphae penetration within the next {critical_window_hours} hours."
            )
            preventive_actions = [
                "Drain standing water from furrows to reduce canopy relative humidity.",
                "Apply prophylactic bio-shield (Pseudomonas fluorescens 0.5% or Trichoderma viride) within 24h.",
                "Avoid nitrogenous top-dressing fertilizer which promotes lush, susceptible succulent leaf tissue."
            ]
        elif sgi >= 0.40:
            risk_category = "MODERATE_MICROCLIMATE_RISK"
            forecast_message = (
                f"Moderate micro-climate risk for {target_disease}. "
                "Conditions favor spore survival. Monitor field closely."
            )
            preventive_actions = [
                "Inspect lower canopy leaves during early morning dew hours.",
                "Ensure weed-free field borders to improve air circulation."
            ]
        else:
            risk_category = "LOW_MICROCLIMATE_RISK"
            forecast_message = f"Canopy micro-climate is unfavorable for {target_disease} spore germination."
            preventive_actions = [
                "Maintain normal crop irrigation schedule."
            ]

        return {
            "crop": crop,
            "target_pathogen": target_disease,
            "spore_germination_index_pct": sgi_pct,
            "risk_classification": risk_category,
            "calculated_dew_point_c": dew_point,
            "effective_leaf_wetness_hours": round(effective_lwd, 1),
            "critical_infection_window_hours": critical_window_hours,
            "physics_forecast_summary": forecast_message,
            "preventive_canopy_actions": preventive_actions
        }


bio_twin_engine = PhysicsBioTwinEngine()