package service

import (
	"fmt"
	"strings"

	"silk-server-go/internal/model"
)

// WeatherTextRainy 天气现象是否降雨/雷/雪
func WeatherTextRainy(text string) bool {
	return strings.Contains(text, "雨") || strings.Contains(text, "雷") || strings.Contains(text, "雪")
}

// RainDays 预报中降雨天数
func RainDays(daily []DailyForecast) int {
	n := 0
	for _, d := range daily {
		if WeatherTextRainy(d.TextDay) || WeatherTextRainy(d.TextNight) {
			n++
		}
	}
	return n
}

// FungalRisk 白僵病：湿度 ≥80% 且（连续阴雨 ≥2 天 或 当前降雨）
func FungalRisk(now WeatherNow, daily []DailyForecast) (string, string) {
	if now.Humidity >= 80 && (RainDays(daily) >= 2 || WeatherTextRainy(now.Text)) {
		return "orange", fmt.Sprintf("实时湿度 %.0f%% 且未来 %d 天有降雨（连续阴雨），符合白僵病高发条件（湿度大于80）", now.Humidity, RainDays(daily))
	}
	return "", ""
}

// TempSwingRisk 核型多角体病：温度突变（>30℃ 或 <20℃）
func TempSwingRisk(temp float64) (string, string) {
	if temp > 30 || temp < 20 {
		return "yellow", fmt.Sprintf("实时温度 %.0f℃ 波动剧烈（>30℃ 或 <20℃），易诱发核型多角体病潜伏感染转急性", temp)
	}
	return "", ""
}

// SofteningRisk 软化病：湿度 >75%（结合密度/通风可升级）
func SofteningRisk(now WeatherNow) (string, string) {
	if now.Humidity >= 75 {
		return "yellow", fmt.Sprintf("实时湿度 %.0f%%（大于75），若蚕头密度过大、通风不良易发软化病", now.Humidity)
	}
	return "", ""
}

// EvaluateWeatherRules 综合天气规则 → 预警列表（规则取自规格书 3.2.3）
func EvaluateWeatherRules(now WeatherNow, daily []DailyForecast, stage string) []model.WeatherAlert {
	var alerts []model.WeatherAlert

	if level, reason := FungalRisk(now, daily); level != "" {
		alerts = append(alerts, model.WeatherAlert{Disease: "白僵病", Level: level, Reason: reason})
	}
	if level, reason := TempSwingRisk(now.Temp); level != "" {
		if stage == "late5" {
			level = "orange"
			reason += "；当前为 5 龄后期，风险升级"
		}
		alerts = append(alerts, model.WeatherAlert{Disease: "核型多角体病", Level: level, Reason: reason})
	}
	if level, reason := SofteningRisk(now); level != "" {
		alerts = append(alerts, model.WeatherAlert{Disease: "软化病", Level: level, Reason: reason})
	}
	return alerts
}