"""
Professional Alert Decision Engine
===================================
Generates real-time alerts based on weather, pest, and water data
Follows climate-resilient agriculture best practices
"""

import logging
from datetime import datetime
from typing import List, Dict, Optional

logger = logging.getLogger("DecisionEngine")

# Alert severity constants
SEVERITY_CRITICAL = "CRITICAL"
SEVERITY_HIGH = "HIGH"
SEVERITY_MEDIUM = "MEDIUM"
SEVERITY_LOW = "LOW"
SEVERITY_INFO = "INFO"

def calculate_climate_resilience_score(w_intel: Dict, p_intel: Dict, water_intel: Dict, farmer: Dict) -> Dict:
    """Calculate comprehensive climate resilience index (0-100)"""
    
    score_components = {}
    
    # Weather Risk (30 points max)
    curr = w_intel.get("current", {})
    temp = curr.get("temp", 25)
    wind = curr.get("wind", 0)
    forecast = w_intel.get("forecast", [])
    
    weather_score = 30
    if temp > farmer.get("threshold_settings", {}).get("temp_high", 40):
        weather_score -= 15
    elif temp < farmer.get("threshold_settings", {}).get("temp_low", 5):
        weather_score -= 10
    
    if wind > farmer.get("threshold_settings", {}).get("wind_speed", 30):
        weather_score -= 15
    
    heavy_rain_days = len([d for d in forecast if "heavy" in d.get("description", "").lower()])
    if heavy_rain_days > 2:
        weather_score -= 5 * heavy_rain_days
    
    score_components["weather_risk"] = max(0, weather_score)
    
    # Pest Risk (30 points max)
    pest_score = 30
    for pest in p_intel.get("pest_prediction_table", []):
        severity = pest.get("severity", "").upper()
        if severity == "CRITICAL":
            pest_score -= 15
        elif severity == "HIGH":
            pest_score -= 10
        elif severity == "MEDIUM":
            pest_score -= 5
    
    score_components["pest_risk"] = max(0, pest_score)
    
    # Water Management Risk (20 points max)
    water_score = 20
    irrigation_minutes = water_intel.get("irrigation_minutes", 0)
    water_m3 = water_intel.get("water_m3_sqm", 0)
    
    # Optimal range: 20-40 minutes
    if irrigation_minutes < 20 or irrigation_minutes > 50:
        water_score -= 10
    
    score_components["water_risk"] = max(0, water_score)
    
    # Resource Efficiency (20 points max)
    efficiency_score = 20
    rain_next_7days = len([d for d in forecast if "rain" in d.get("description", "").lower()])
    
    # More rain = less irrigation needed = better efficiency
    if rain_next_7days > 2:
        efficiency_score = 20
    elif irrigation_minutes > 40:
        efficiency_score = 10
    
    score_components["resource_efficiency"] = efficiency_score
    
    total_score = sum([score_components["weather_risk"], 
                       score_components["pest_risk"], 
                       score_components["water_risk"],
                       score_components["resource_efficiency"]])
    
    resilience_level = "🟢 GREEN" if total_score >= 75 else "🟡 YELLOW" if total_score >= 50 else "🔴 RED"
    
    return {
        "total_score": total_score,
        "components": score_components,
        "resilience_level": resilience_level,
        "critical_factors": [k for k, v in score_components.items() if v < 15]
    }

def get_alerts(w_intel: Dict, p_intel: Dict, water_intel: Dict, farmer: Dict) -> List[Dict]:
    """
    Generate actionable alerts with severity levels
    Returns list of professional farm alerts
    """
    alerts = []
    
    # Core Data Extraction
    curr = w_intel.get("current", {})
    temp = curr.get("temp", 25)
    humidity = curr.get("humidity", 60)
    wind = curr.get("wind", 0)
    forecast = w_intel.get("forecast", [])
    
    thresholds = farmer.get("threshold_settings", {})
    
    rain_next_24h = any("rain" in d.get("description", "").lower() for d in forecast[:2])
    heavy_rain_forecast = [d for d in forecast if "heavy" in d.get("description", "").lower()]
    
    # ════════════════════════════════════════════════════════════════════════════
    # 1️⃣ CRITICAL WEATHER ALERTS
    # ════════════════════════════════════════════════════════════════════════════
    
    if temp > thresholds.get("temp_high", 40):
        alerts.append({
            "type": "WEATHER",
            "id": "EXTREME_HEAT",
            "severity": SEVERITY_CRITICAL,
            "title": "🌡️ EXTREME HEAT WARNING",
            "message": f"Temperature reached {temp}°C. Immediate irrigation required.",
            "action": "IRRIGATE_IMMEDIATELY",
            "details": {
                "current_temp": temp,
                "threshold": thresholds.get("temp_high", 40),
                "expected_crop_loss": "25-35%" if temp > 45 else "15-20%",
                "hydration_urgency": "CRITICAL"
            },
            "action_items": [
                f"🚨 Start irrigation within next 30 minutes",
                "💧 Increase water supply by 20-30%",
                "🌳 Consider temporary shade if available",
                "📊 Monitor soil moisture every 2 hours"
            ]
        })
    
    if wind > thresholds.get("wind_speed", 30):
        alerts.append({
            "type": "WEATHER",
            "id": "SEVERE_WIND",
            "severity": SEVERITY_CRITICAL,
            "title": "🌪️ SEVERE WIND WARNING",
            "message": f"Wind speed {wind} km/h. High crop damage risk.",
            "action": "AVOID_ALL_OPERATIONS",
            "details": {
                "wind_speed": wind,
                "risk_level": "CRITICAL",
                "expected_damage": "Physical damage to plants, fruit drop"
            },
            "action_items": [
                "⛔ Stop all spraying and pesticide application",
                "🔧 Secure loose equipment and stakes",
                "📍 Postpone harvesting activities",
                "🌾 Support weak branches with stakes"
            ]
        })
    
    if temp < thresholds.get("temp_low", 5):
        alerts.append({
            "type": "WEATHER",
            "id": "FROST_RISK",
            "severity": SEVERITY_HIGH,
            "title": "❄️ FROST RISK - CROP PROTECTION NEEDED",
            "message": f"Temperature dropping to {temp}°C. Frost damage imminent.",
            "action": "PROTECT_CROP",
            "details": {
                "current_temp": temp,
                "frost_risk": "HIGH",
                "vulnerable_stages": "Flowering and young fruits"
            },
            "action_items": [
                "🔥 Prepare frost protection measures (smudging/overhead irrigation)",
                "💨 Use wind machines if available",
                "🌫️ Apply antitranspirants to sensitive crops",
                "📞 Contact agricultural extension for emergency support"
            ]
        })
    
    # ════════════════════════════════════════════════════════════════════════════
    # 2️⃣ HEAVY RAIN & FLOODING ALERTS
    # ════════════════════════════════════════════════════════════════════════════
    
    if heavy_rain_forecast:
        alerts.append({
            "type": "WEATHER",
            "id": "HEAVY_RAIN_WARNING",
            "severity": SEVERITY_HIGH,
            "title": f"🌧️ HEAVY RAIN WARNING - {len(heavy_rain_forecast)} days",
            "message": f"Heavy rainfall expected. Prepare drainage systems.",
            "action": "PREPARE_DRAINAGE",
            "details": {
                "days_affected": len(heavy_rain_forecast),
                "flooding_risk": "HIGH",
                "drainage_priority": "URGENT"
            },
            "action_items": [
                "💧 Clear all drainage channels and ditches",
                "🔨 Repair broken drainage pipes immediately",
                "🪴 Avoid planting in low-lying areas",
                "⚙️ Test pump systems before heavy rain",
                "📊 Monitor water levels in fields"
            ]
        })
        
        if not rain_next_24h or wind > thresholds.get("wind_alert", 15):
            alerts.append({
                "type": "SPRAY_OPERATIONS",
                "id": "UNSAFE_SPRAY_WINDOW",
                "severity": SEVERITY_HIGH,
                "title": "🚫 UNSAFE TO SPRAY",
                "message": f"Rain or high wind (Wind: {wind} km/h). Postpone spraying.",
                "action": "POSTPONE_SPRAYING",
                "details": {
                    "wind_speed": wind,
                    "rain_probability": "HIGH",
                    "spray_loss_rate": "60-70%"
                },
                "action_items": [
                    "⏰ Postpone pesticide/fertilizer application",
                    "📅 Reschedule for 3-5 days later",
                    "💰 Higher wind causes 60-70% spray drift loss",
                    "📍 Mark postponed tasks for follow-up"
                ]
            })
    elif not rain_next_24h and wind < thresholds.get("wind_alert", 15):
        alerts.append({
            "type": "SPRAY_OPERATIONS",
            "id": "OPTIMAL_SPRAY_WINDOW",
            "severity": SEVERITY_INFO,
            "title": "✅ OPTIMAL SPRAY WINDOW",
            "message": "Ideal conditions for spraying. Good wind and no rain.",
            "action": "APPLY_INPUTS",
            "details": {
                "wind_speed": wind,
                "spray_efficiency": "95-98%",
                "window_duration": "5-7 PM optimal"
            },
            "action_items": [
                "⏱️ Plan spraying activities for 5-7 PM (optimal wind)",
                "🎯 Use this window for pesticide/herbicide application",
                "💡 Higher efficiency = reduced chemical usage = cost savings",
                "📊 Monitor weather updates continuously"
            ]
        })
    
    # ════════════════════════════════════════════════════════════════════════════
    # 3️⃣ PEST & DISEASE ALERTS
    # ════════════════════════════════════════════════════════════════════════════
    
    for pest in p_intel.get("pest_prediction_table", []):
        severity = pest.get("severity", "").upper()
        pest_name = pest.get("pest_name", "Unknown Pest")
        confidence = pest.get("confidence", 50)
        
        if severity in ["CRITICAL", "HIGH"]:
            alert_severity = SEVERITY_CRITICAL if severity == "CRITICAL" else SEVERITY_HIGH
            alerts.append({
                "type": "PEST_ALERT",
                "id": f"PEST_{pest_name.upper().replace(' ', '_')}",
                "severity": alert_severity,
                "title": f"🐛 {pest_name.upper()} ALERT",
                "message": f"High {pest_name} infestation risk detected ({confidence}% confidence).",
                "action": "PEST_MANAGEMENT",
                "details": {
                    "pest": pest_name,
                    "risk_level": severity,
                    "confidence": confidence,
                    "favorable_temp": f"{temp}°C is {'FAVORABLE' if 20 <= temp <= 30 else 'UNFAVORABLE'} for {pest_name}",
                    "humidity_level": f"Current: {humidity}% - {'High risk' if humidity > 70 else 'Moderate risk'}"
                },
                "action_items": [
                    f"🔍 Scout fields immediately for {pest_name} symptoms",
                    f"🧪 Start bioagent/chemical control within 48 hours",
                    f"📸 Document infestation level (% affected plants)",
                    f"📞 Contact agricultural extension for spray recommendations",
                    f"⏰ Plan early morning or late evening spraying (5-7 PM optimal)"
                ]
            })
    
    # ════════════════════════════════════════════════════════════════════════════
    # 4️⃣ IRRIGATION MANAGEMENT ALERTS
    # ════════════════════════════════════════════════════════════════════════════
    
    water_m3 = water_intel.get("water_m3_sqm", 0)
    irrigation_minutes = water_intel.get("irrigation_minutes", 0)
    
    if water_m3 > 0.15 or (temp > 35 and water_m3 > 0.1):
        alerts.append({
            "type": "IRRIGATION",
            "id": "IMMEDIATE_IRRIGATION_NEEDED",
            "severity": SEVERITY_CRITICAL if temp > 35 else SEVERITY_HIGH,
            "title": "💧 IRRIGATION REQUIRED",
            "message": f"Soil water deficit: {water_m3:.3f} m³. Start irrigation NOW.",
            "action": "IRRIGATE_IMMEDIATELY",
            "details": {
                "water_needed": f"{water_m3:.3f} m³/m²",
                "irrigation_duration_minutes": round(irrigation_minutes),
                "soil_moisture_status": "CRITICAL" if water_m3 > 0.15 else "LOW",
                "temperature_stress": "YES" if temp > 35 else "NO"
            },
            "action_items": [
                f"⏱️ Start irrigation for {round(irrigation_minutes)} minutes",
                f"💧 Deliver {water_m3:.2f} m³ per m² of field",
                "🌡️ Best timing: Early morning (5-7 AM) or evening (6-8 PM)",
                "📊 Check soil moisture after irrigation completion",
                "📈 Monitor evapotranspiration for next irrigation schedule"
            ]
        })
    
    elif 0.05 < water_m3 <= 0.15:
        alerts.append({
            "type": "IRRIGATION",
            "id": "IRRIGATION_SCHEDULED",
            "severity": SEVERITY_MEDIUM,
            "title": "💧 IRRIGATION SCHEDULED",
            "message": f"Plan irrigation soon. Water needed: {water_m3:.3f} m³",
            "action": "SCHEDULE_IRRIGATION",
            "details": {
                "water_needed": f"{water_m3:.3f} m³/m²",
                "irrigation_duration_minutes": round(irrigation_minutes),
                "best_window": "Next 48-72 hours"
            },
            "action_items": [
                f"📅 Schedule irrigation in next 2-3 days",
                f"⏱️ Duration: {round(irrigation_minutes)} minutes",
                f"💧 Water quantity: {water_m3:.2f} m³/m²",
                "🌞 Avoid midday irrigation (high evaporation)",
                "🧹 Remove weeds before irrigation (better water use)"
            ]
        })
    
    else:
        alerts.append({
            "type": "IRRIGATION",
            "id": "IRRIGATION_OPTIMAL",
            "severity": SEVERITY_INFO,
            "title": "✅ SOIL MOISTURE OPTIMAL",
            "message": "Current soil moisture is adequate. Monitor regularly.",
            "action": "MONITOR",
            "details": {
                "water_status": "OPTIMAL",
                "next_check": "48 hours"
            }
        })
    
    # ════════════════════════════════════════════════════════════════════════════
    # 5️⃣ CLIMATE RESILIENCE & SUSTAINABILITY ALERTS
    # ════════════════════════════════════════════════════════════════════════════
    
    resilience = calculate_climate_resilience_score(w_intel, p_intel, water_intel, farmer)
    
    if resilience["total_score"] < 50:
        alerts.append({
            "type": "CLIMATE_RESILIENCE",
            "id": "LOW_RESILIENCE_ALERT",
            "severity": SEVERITY_HIGH,
            "title": "⚠️ LOW CLIMATE RESILIENCE INDEX",
            "message": f"Farm resilience score: {resilience['total_score']:.0f}/100. Multiple risks detected.",
            "action": "IMPLEMENT_RESILIENCE_MEASURES",
            "details": resilience,
            "action_items": [
                "🌾 Implement mulching to reduce water loss 30-40%",
                "🌱 Plant nitrogen-fixing legumes for soil health",
                "💨 Establish windbreaks for wind protection",
                "🔄 Diversify crops to reduce single-pest risk",
                "💰 Consider insurance schemes for climate risks"
            ]
        })
    
    # Sustainability Tips based on conditions
    if irrigation_minutes > 40:
        alerts.append({
            "type": "SUSTAINABILITY",
            "id": "WATER_CONSERVATION_TIP",
            "severity": SEVERITY_INFO,
            "title": "💧 WATER CONSERVATION OPPORTUNITY",
            "message": "High irrigation need. Implement water-saving techniques.",
            "action": "CONSERVATION_MEASURE",
            "details": {
                "current_irrigation_time": round(irrigation_minutes),
                "potential_savings": "30-40%"
            },
            "action_items": [
                "🌾 Apply mulch (straw/leaves) to reduce evaporation by 40%",
                "🌱 Use drip irrigation if available (saves 50% water vs. flood)",
                "💨 Install wind breaks to reduce evaporative stress",
                "🕐 Irrigate early morning (5-7 AM) to minimize evaporation",
                "📊 Monitor soil moisture with meter for precision"
            ]
        })
    else:
        alerts.append({
            "type": "SUSTAINABILITY",
            "id": "SUSTAINABLE_PRACTICE_TIP",
            "severity": SEVERITY_INFO,
            "title": "🌍 SUSTAINABLE FARMING TIP",
            "message": "Implement intercropping for natural pest control.",
            "action": "IMPLEMENT_PRACTICE",
            "details": {
                "practice": "Intercropping with legumes",
                "benefit": "30-40% reduction in pest incidence, soil nitrogen boost"
            },
            "action_items": [
                "🌱 Intercrop with legumes (beans, peas) to fix nitrogen",
                "🐝 Attract pollinators with flowering plants at field edges",
                "🐛 Encourage beneficial insects (ladybugs, parasitoid wasps)",
                "♻️ Use crop residue for compost instead of burning",
                "📈 Expected yield increase: 15-20% with better soil health"
            ]
        })
    
    logger.info(f"✅ Generated {len(alerts)} alerts for {farmer.get('name', 'Farmer')}")
    return alerts