package service

import (
	"fmt"
	"time"
)

// EnvSample 环境回溯样本
type EnvSample struct {
	Time     time.Time
	Temp     *float64
	Humidity *float64
}

// EnvironmentResult 环境回溯结果
type EnvironmentResult struct {
	HighHumidity bool
	TempSwing    bool
	Summary      string
}

// EnvironmentBacktrack 发病前环境回溯：湿度≥阈值 或 温度>30/<20 触发（规格书 3.8.3）
func EnvironmentBacktrack(samples []EnvSample, humidityThreshold float64) EnvironmentResult {
	r := EnvironmentResult{}
	if len(samples) == 0 {
		r.Summary = "无可用环境遥测数据"
		return r
	}
	for _, s := range samples {
		if s.Humidity != nil && *s.Humidity >= humidityThreshold {
			r.HighHumidity = true
		}
		if s.Temp != nil && (*s.Temp > 30 || *s.Temp < 20) {
			r.TempSwing = true
		}
	}
	switch {
	case r.HighHumidity && r.TempSwing:
		r.Summary = "发病前环境存在持续高湿与温度突变，符合真菌病与核型多角体病诱发条件"
	case r.HighHumidity:
		r.Summary = fmt.Sprintf("发病前环境湿度 ≥%.0f%%，符合高湿诱病条件", humidityThreshold)
	case r.TempSwing:
		r.Summary = "发病前环境温度突变（>30℃ 或 <20℃），易诱发潜伏感染转急性"
	default:
		r.Summary = "发病前环境温湿度未见明显异常"
	}
	return r
}

// PastEvent 历史发病事件
type PastEvent struct {
	Disease string
	DaysAgo int
}

// HistoryAssociation 历史发病关联：同房间/同病种既往 90 天内有发病 → 连发性
func HistoryAssociation(past []PastEvent, disease string) bool {
	for _, e := range past {
		if e.Disease == disease && e.DaysAgo <= 90 {
			return true
		}
	}
	return false
}

// TransmissionInference 按病种推断传播途径（规格书 3.8.2）
func TransmissionInference(disease string) (mode, source string) {
	switch disease {
	case "核型多角体病":
		return "食下传染为主，创伤传染次之", "多角体污染蚕座/桑叶/蚕具，环境残留或新引入"
	case "白僵病", "其他真菌病（绿僵病/黄僵病/曲霉病）":
		return "接触传染/气流扩散", "分生孢子经气流带入，或蚕房尸体产孢内源扩散"
	case "软化病", "浓核病/传染性软化病":
		return "食下传染", "桑园害虫粪便污染桑叶，或蚕座环境累积污染"
	case "微粒子病":
		return "食下传染+胚种传染", "蚕种带毒（垂直传播）或环境孢子水平传播"
	case "细菌性败血病":
		return "创伤传染", "蚕具刮伤/互相抓伤后环境细菌侵入"
	case "猝倒病":
		return "食下传染（细菌毒素）", "桑叶被细菌污染"
	default:
		return "未知", "病种不明，建议先确认病原"
	}
}

// ChecklistItem 排查清单项
type ChecklistItem struct {
	Key          string `json:"key"`
	Label        string `json:"label"`
	InternalBias bool   `json:"internalBias"`
}

// DiseaseChecklist 分病种二级排查清单（规格书 3.8.3）
func DiseaseChecklist(disease string) []ChecklistItem {
	switch disease {
	case "核型多角体病":
		return []ChecklistItem{
			{Key: "disinfect", Label: "上批次是否发生过同种病？消毒是否彻底（含蚕具浸泡）？", InternalBias: true},
			{Key: "tray_share", Label: "蚕具是否跨批次共用？", InternalBias: true},
			{Key: "mulberry", Label: "桑叶来源是否变更？", InternalBias: false},
			{Key: "entry", Label: "近期人员进出/蚕具借用记录是否有异常？", InternalBias: false},
		}
	case "白僵病":
		return []ChecklistItem{
			{Key: "vent", Label: "近期是否连续阴雨且通风不足？", InternalBias: true},
			{Key: "corpse", Label: "蚕房附近是否堆放蚕沙或病蚕尸体？", InternalBias: true},
			{Key: "outdoor", Label: "蚕房周边桑园昆虫是否有白僵病死亡个体？", InternalBias: false},
			{Key: "filter", Label: "通风口是否有过滤防虫措施？", InternalBias: false},
		}
	case "微粒子病":
		return []ChecklistItem{
			{Key: "seed", Label: "蚕种来源批次与供应商是否可追溯？", InternalBias: true},
			{Key: "quarantine", Label: "检疫证明与母蛾镜检结果是否齐全？", InternalBias: true},
			{Key: "wild", Label: "桑园周边野外昆虫是否有微孢子虫？", InternalBias: false},
			{Key: "cross", Label: "同批次蚕种在其他蚕房是否发病？", InternalBias: false},
		}
	case "软化病", "浓核病/传染性软化病":
		return []ChecklistItem{
			{Key: "density", Label: "蚕头密度是否过大？", InternalBias: true},
			{Key: "vent", Label: "通风是否不良？", InternalBias: true},
			{Key: "mulberry", Label: "桑叶是否潮湿或储运不达标？", InternalBias: true},
			{Key: "pest", Label: "桑园近期害虫防治记录是否正常？", InternalBias: false},
		}
	case "细菌性败血病":
		return []ChecklistItem{
			{Key: "tool", Label: "蚕具是否有尖锐边缘/毛刺？", InternalBias: true},
			{Key: "density", Label: "蚕头密度是否超标导致相互抓伤？", InternalBias: true},
			{Key: "op", Label: "给桑操作是否粗暴？", InternalBias: true},
			{Key: "disinfect", Label: "消毒是否有盲区？", InternalBias: true},
		}
	default:
		return nil
	}
}

// ChecklistAnswer 清单作答
type ChecklistAnswer struct {
	Key          string `json:"key"`
	Label        string `json:"label"`
	Answer       string `json:"answer"` // yes/no/unknown
	InternalBias bool   `json:"internalBias"`
}

// AnalyzeChecklist 按作答统计内源/外源倾向并给出结论
func AnalyzeChecklist(answers []ChecklistAnswer) (origin string, confidence float64, conclusion string) {
	internal, external, unknown := 0, 0, 0
	for _, a := range answers {
		switch a.Answer {
		case "yes":
			if a.InternalBias {
				internal++
			} else {
				external++
			}
		case "no":
			if a.InternalBias {
				external++
			} else {
				internal++
			}
		default:
			unknown++
		}
	}
	total := internal + external + unknown
	if total == 0 {
		return "unknown", 0, "未填写排查清单，无法判定来源"
	}
	switch {
	case internal > external:
		origin = "internal"
		confidence = 0.5 + 0.3*float64(internal)/float64(total)
		conclusion = "倾向内源扩散（环境残留/蚕座污染），建议定向清除环境残留并升级消毒"
	case external > internal:
		origin = "external"
		confidence = 0.5 + 0.3*float64(external)/float64(total)
		conclusion = "倾向外源侵入（桑叶/气流/种源），建议封堵外部侵入途径"
	default:
		origin = "unknown"
		confidence = 0.5
		conclusion = "内源与外源线索相当，建议结合专家会诊进一步确认"
	}
	return origin, confidence, conclusion
}