package mcp

import (
	"context"
	"strings"
	"time"

	"yunyan/comm"
	"yunyan/lego/core"
	"yunyan/lego/core/cbase"
	"yunyan/lego/sys/mysql"
	"yunyan/pb"
	"yunyan/utils"

	"github.com/mark3labs/mcp-go/mcp"
)

/*
记忆中心（拾忆）的 MCP 工具：让 EMAI 能回答「我明天有什么事」「这个月花了多少」。

## 只读

新增/修改/删除**不放在这里**。写路径的校验、幂等（client_key）、提醒时刻重算
都在 home 的 memory 模块内，在 MCP 里复制一份必然漂移。
录入走端侧指令（tool_calls），查询走 MCP —— 这个分工是刻意的。

## 身份

uid 一律从 Authorization 的 JWT 解（见 auth.go），**不信任模型传的参数**。
*/

// ---------- get_memory_items ----------

type tool_get_memory_items struct {
	cbase.ModuleCompBase
	module *Mcp
}

func (this *tool_get_memory_items) Init(service core.IService, module core.IModule, comp core.IModuleComp, opt core.IModuleOptions) (err error) {
	this.ModuleCompBase.Init(service, module, comp, opt)
	this.module = module.(*Mcp)
	return
}

func (this *tool_get_memory_items) Start() (err error) {
	err = this.ModuleCompBase.Start()
	this.module.AddTool(ToolGroup_GLOBAL, this.Tool(), this.Handl)
	return
}

func (this *tool_get_memory_items) Tool() mcp.Tool {
	return mcp.NewTool("get_memory_items",
		mcp.WithDescription("查询用户记录的事项（待办/闹钟/灵感/花销），可按时间范围与分类筛选"),
		mcp.WithString("range",
			mcp.Description("相对时间范围，取值："+strings.Join(comm.MemoryRelativeRanges, "/")+
				"。与 start_date/end_date 二选一，优先用本字段"),
		),
		mcp.WithString("start_date", mcp.Description("起始日期 YYYY-MM-DD")),
		mcp.WithString("end_date", mcp.Description("结束日期 YYYY-MM-DD")),
		mcp.WithString("category",
			mcp.Description("分类筛选：todo=待办 alarm=闹钟 idea=灵感 expense=花销，留空=全部"),
		),
		mcp.WithNumber("limit", mcp.Description("返回条数上限（默认50，最大200）"), mcp.DefaultNumber(50)),
	)
}

func (this *tool_get_memory_items) Handl(ctx context.Context, request mcp.CallToolRequest) (*mcp.CallToolResult, error) {
	uid, err := this.module.ResolveUID(ctx, request.GetString("uid", ""))
	if err != nil {
		return mcp.NewToolResultError(err.Error()), nil
	}
	start, end, errRange := resolveRange(request)
	if errRange != nil {
		return mcp.NewToolResultError(errRange.Error()), nil
	}

	var cats []string
	if c := strings.TrimSpace(request.GetString("category", "")); c != "" {
		// 模型填错分类不该让整次查询失败——忽略非法值当作"不限分类"，
		// 比返回一个错误让它重试要好（它多半会再填错一次）。
		cats, _ = comm.NormalizeMemoryCategories([]string{c})
	}

	limit := int(request.GetInt("limit", 50))
	if limit <= 0 || limit > 200 {
		limit = 50
	}

	items := make([]*pb.DBMemoryItem, 0)
	tx := comm.ApplyMemoryQuery(mysql.Table(comm.TableMemoryItem), comm.MemoryQuery{
		Uid: uid, StartDate: start, EndDate: end, Categories: cats,
	})
	if e := comm.OrderMemoryItems(tx).Limit(limit).Find(&items).Error; e != nil {
		this.module.Errorln("get_memory_items error:", e)
		return mcp.NewToolResultError("查询失败"), nil
	}

	return mcp.NewToolResultText(utils.ToString(map[string]interface{}{
		"result":     "success",
		"start_date": start,
		"end_date":   end,
		"total":      len(items),
		"items":      briefItems(items),
	})), nil
}

// ---------- get_memory_stats ----------

type tool_get_memory_stats struct {
	cbase.ModuleCompBase
	module *Mcp
}

func (this *tool_get_memory_stats) Init(service core.IService, module core.IModule, comp core.IModuleComp, opt core.IModuleOptions) (err error) {
	this.ModuleCompBase.Init(service, module, comp, opt)
	this.module = module.(*Mcp)
	return
}

func (this *tool_get_memory_stats) Start() (err error) {
	err = this.ModuleCompBase.Start()
	this.module.AddTool(ToolGroup_GLOBAL, this.Tool(), this.Handl)
	return
}

func (this *tool_get_memory_stats) Tool() mcp.Tool {
	return mcp.NewTool("get_memory_stats",
		mcp.WithDescription("统计用户某段时间的待办完成情况、灵感数量与花销合计"),
		mcp.WithString("range",
			mcp.Description("相对时间范围，取值："+strings.Join(comm.MemoryRelativeRanges, "/")),
		),
		mcp.WithString("start_date", mcp.Description("起始日期 YYYY-MM-DD")),
		mcp.WithString("end_date", mcp.Description("结束日期 YYYY-MM-DD")),
	)
}

func (this *tool_get_memory_stats) Handl(ctx context.Context, request mcp.CallToolRequest) (*mcp.CallToolResult, error) {
	uid, err := this.module.ResolveUID(ctx, request.GetString("uid", ""))
	if err != nil {
		return mcp.NewToolResultError(err.Error()), nil
	}
	start, end, errRange := resolveRange(request)
	if errRange != nil {
		return mcp.NewToolResultError(errRange.Error()), nil
	}

	type catCount struct {
		Category string
		State    int32
		N        int64
	}
	rows := make([]catCount, 0)
	if e := comm.ApplyMemoryQuery(mysql.Table(comm.TableMemoryItem),
		comm.MemoryQuery{Uid: uid, StartDate: start, EndDate: end}).
		Select("category, state, count(*) as n").Group("category, state").
		Find(&rows).Error; e != nil {
		this.module.Errorln("get_memory_stats error:", e)
		return mcp.NewToolResultError("统计失败"), nil
	}

	var todoTotal, todoDone, alarmTotal, ideaCount int64
	for _, r := range rows {
		switch r.Category {
		case comm.MemoryCatTodo:
			todoTotal += r.N
			if r.State == int32(pb.MemoryState_MemoryState_Done) {
				todoDone += r.N
			}
		case comm.MemoryCatAlarm:
			alarmTotal += r.N
		case comm.MemoryCatIdea:
			ideaCount += r.N
		}
	}

	// 花销**按币种分行**，不做汇率换算：把 CNY 和 JPY 加成一个数是错的。
	type expRow struct {
		Currency   string
		TotalCents int64
		Count      int64
	}
	exps := make([]expRow, 0)
	if e := comm.ApplyMemoryQuery(mysql.Table(comm.TableMemoryItem),
		comm.MemoryQuery{Uid: uid, StartDate: start, EndDate: end,
			Categories: []string{comm.MemoryCatExpense}}).
		Select("currency, sum(amount_cents) as total_cents, count(*) as count").
		Group("currency").Find(&exps).Error; e != nil {
		this.module.Errorln("get_memory_stats expense error:", e)
		return mcp.NewToolResultError("统计失败"), nil
	}
	expOut := make([]map[string]interface{}, 0, len(exps))
	for _, e := range exps {
		expOut = append(expOut, map[string]interface{}{
			"currency": e.Currency,
			// 同时给「分」和「元」：模型直接念「元」不容易错，
			// 但保留「分」以免它想自己做加减时用浮点数
			"total_cents": e.TotalCents,
			"total":       float64(e.TotalCents) / 100.0,
			"count":       e.Count,
		})
	}

	return mcp.NewToolResultText(utils.ToString(map[string]interface{}{
		"result":      "success",
		"start_date":  start,
		"end_date":    end,
		"todo_total":  todoTotal,
		"todo_done":   todoDone,
		"todo_undone": todoTotal - todoDone,
		"alarm_total": alarmTotal,
		"idea_count":  ideaCount,
		"expenses":    expOut,
	})), nil
}

// ---------- get_memory_report ----------

type tool_get_memory_report struct {
	cbase.ModuleCompBase
	module *Mcp
}

func (this *tool_get_memory_report) Init(service core.IService, module core.IModule, comp core.IModuleComp, opt core.IModuleOptions) (err error) {
	this.ModuleCompBase.Init(service, module, comp, opt)
	this.module = module.(*Mcp)
	return
}

func (this *tool_get_memory_report) Start() (err error) {
	err = this.ModuleCompBase.Start()
	this.module.AddTool(ToolGroup_GLOBAL, this.Tool(), this.Handl)
	return
}

func (this *tool_get_memory_report) Tool() mcp.Tool {
	return mcp.NewTool("get_memory_report",
		mcp.WithDescription("获取用户的周报或月报（系统定期生成的总结）"),
		mcp.WithString("period_type",
			mcp.Description("week=周报 month=月报"),
			mcp.DefaultString("week"),
		),
		mcp.WithString("period_key",
			mcp.Description("周期标识，周报形如 2026-W35，月报形如 2026-08；留空=最近一份"),
		),
	)
}

func (this *tool_get_memory_report) Handl(ctx context.Context, request mcp.CallToolRequest) (*mcp.CallToolResult, error) {
	uid, err := this.module.ResolveUID(ctx, request.GetString("uid", ""))
	if err != nil {
		return mcp.NewToolResultError(err.Error()), nil
	}
	ptype := strings.ToLower(strings.TrimSpace(request.GetString("period_type", comm.MemoryPeriodWeek)))
	if ptype != comm.MemoryPeriodWeek && ptype != comm.MemoryPeriodMonth {
		ptype = comm.MemoryPeriodWeek
	}
	pkey := strings.TrimSpace(request.GetString("period_key", ""))

	recs := make([]*pb.DBMemoryReport, 0)
	tx := mysql.Table(comm.TableMemoryReport).
		Where("uid = ? and period_type = ?", uid, ptype).
		// 只给已生成完的：还在生成中的报告 summary 是空的，
		// 给出去只会让模型编一段话填空。
		Where("state = ?", int32(pb.MemoryReportState_MemoryReportState_Done))
	if pkey != "" {
		tx = tx.Where("period_key = ?", pkey)
	}
	if e := tx.Order("period_end desc").Limit(1).Find(&recs).Error; e != nil {
		this.module.Errorln("get_memory_report error:", e)
		return mcp.NewToolResultError("查询失败"), nil
	}
	if len(recs) == 0 {
		return mcp.NewToolResultText(utils.ToString(map[string]interface{}{
			"result": "empty", "message": "还没有生成过对应的报告",
		})), nil
	}
	r := recs[0]
	return mcp.NewToolResultText(utils.ToString(map[string]interface{}{
		"result":       "success",
		"period_type":  r.PeriodType,
		"period_key":   r.PeriodKey,
		"period_start": r.PeriodStart,
		"period_end":   r.PeriodEnd,
		"summary":      r.Summary,
		"stat":         r.StatJson,
	})), nil
}

// ---------- 公共辅助 ----------

// resolveRange 解析时间范围：range 优先，其次 start_date/end_date，都没有则默认最近 7 天。
//
// 提供 range 这种相对说法是刻意的：模型对「今天几号」的认知来自对话上下文，
// 很不可靠，让它自己算 start_date 经常算错（SET_clock 把「下午 3:30」填成
// 03:30 是同一类问题）。
func resolveRange(request mcp.CallToolRequest) (start, end string, err error) {
	now := time.Now()
	if r := strings.TrimSpace(request.GetString("range", "")); r != "" {
		return comm.MemoryRelativeRange(r, now)
	}
	start = strings.TrimSpace(request.GetString("start_date", ""))
	end = strings.TrimSpace(request.GetString("end_date", ""))
	if start == "" && end == "" {
		return comm.FormatMemoryDate(now.AddDate(0, 0, -7)),
			comm.FormatMemoryDate(now.AddDate(0, 0, 7)), nil
	}
	if start != "" {
		if _, ok := comm.ParseMemoryDate(start); !ok {
			return "", "", errBadDate(start)
		}
	}
	if end != "" {
		if _, ok := comm.ParseMemoryDate(end); !ok {
			return "", "", errBadDate(end)
		}
	}
	return start, end, nil
}

func errBadDate(s string) error {
	return &badDateError{s}
}

type badDateError struct{ v string }

func (e *badDateError) Error() string {
	return "日期格式应为 YYYY-MM-DD：" + e.v
}

// briefItems 只给模型必要字段。
//
// 不把整行 DBMemoryItem 丢过去：那里面有 client_key、gen_round、extra 这类
// 内部字段，对回答问题毫无用处，只会占 token 并诱导模型去解释它们。
func briefItems(items []*pb.DBMemoryItem) []map[string]interface{} {
	out := make([]map[string]interface{}, 0, len(items))
	for _, it := range items {
		m := map[string]interface{}{
			"id":       it.Id,
			"category": it.Category,
			"title":    it.Title,
			"date":     it.HappenDate,
			"done":     it.State == pb.MemoryState_MemoryState_Done,
		}
		if it.HappenTime != "" {
			m["time"] = it.HappenTime
		}
		if it.Detail != "" {
			m["detail"] = it.Detail
		}
		if it.Owner != "" {
			m["owner"] = it.Owner
		}
		if it.DueRaw != "" {
			m["due"] = it.DueRaw
		}
		if it.Category == comm.MemoryCatExpense {
			m["amount"] = float64(it.AmountCents) / 100.0
			m["currency"] = it.Currency
		}
		if !it.DateCertain {
			// 让模型知道这个日期是推断的，别把它当成用户确认过的安排来陈述
			m["date_is_inferred"] = true
		}
		out = append(out, m)
	}
	return out
}