package app

import (
	"database/sql"
	"fmt"
	"net/http"
	"strconv"
	"strings"
)

type aiAgentView struct {
	UserID          int64  `json:"userId"`
	PublicID        string `json:"publicId"`
	Nickname        string `json:"nickname"`
	TestBatch       string `json:"testBatch"`
	Enabled         bool   `json:"enabled"`
	ModelID         int64  `json:"modelId"`
	ModelName       string `json:"modelName"`
	Persona         string `json:"persona"`
	DailyReplyLimit int    `json:"dailyReplyLimit"`
	ReplyCount      int    `json:"replyCount"`
	LastReplyAt     string `json:"lastReplyAt"`
	TodayReplies    int    `json:"todayReplies"`
}

// Only test accounts can be managed, so the list is the test account list with
// its binding attached rather than a separate registry.
func (a *App) adminAIAgents(w http.ResponseWriter, r *http.Request) {
	page, size, offset := pagination(r)
	batch := strings.TrimSpace(r.URL.Query().Get("batch"))
	where, args, err := testUserFilter("test", batch)
	if err != nil {
		fail(w, http.StatusBadRequest, 20001, err.Error())
		return
	}
	if strings.TrimSpace(r.URL.Query().Get("managed")) == "1" {
		where += " AND g.user_id IS NOT NULL AND g.enabled=1"
	}
	var total int
	countArgs := append([]any{}, args...)
	if err = a.db.QueryRowContext(r.Context(), `SELECT COUNT(*) FROM users u
		LEFT JOIN ai_agents g ON g.user_id=u.id
		WHERE u.status=1 AND u.deleted_at IS NULL`+where, countArgs...).Scan(&total); err != nil {
		fail(w, http.StatusInternalServerError, 50001, "查询托管账号失败")
		return
	}
	rows, err := a.db.QueryContext(r.Context(), `SELECT u.id,u.public_id,u.test_batch,p.nickname,
		COALESCE(g.enabled,0),COALESCE(g.model_id,0),COALESCE(g.persona,''),COALESCE(g.daily_reply_limit,0),
		COALESCE(g.reply_count,0),g.last_reply_at,COALESCE(m.name,''),
		(SELECT COUNT(*) FROM ai_call_logs l WHERE l.scene='chat' AND l.agent_user_id=u.id AND l.status=1 AND l.created_at>=CURRENT_DATE())
		FROM users u JOIN user_profiles p ON p.user_id=u.id
		LEFT JOIN ai_agents g ON g.user_id=u.id
		LEFT JOIN ai_models m ON m.id=g.model_id
		WHERE u.status=1 AND u.deleted_at IS NULL`+where+` ORDER BY u.id ASC LIMIT ? OFFSET ?`,
		append(args, size, offset)...)
	if err != nil {
		fail(w, http.StatusInternalServerError, 50001, "查询托管账号失败")
		return
	}
	defer rows.Close()
	items := []aiAgentView{}
	for rows.Next() {
		var item aiAgentView
		var enabled int
		var lastReplyAt sql.NullTime
		if rows.Scan(&item.UserID, &item.PublicID, &item.TestBatch, &item.Nickname, &enabled, &item.ModelID,
			&item.Persona, &item.DailyReplyLimit, &item.ReplyCount, &lastReplyAt, &item.ModelName, &item.TodayReplies) != nil {
			continue
		}
		item.Enabled = enabled == 1
		if lastReplyAt.Valid {
			item.LastReplyAt = lastReplyAt.Time.Format("2006-01-02 15:04")
		}
		items = append(items, item)
	}
	reply(w, map[string]any{"items": items, "page": page, "size": size, "total": total, "enabled": a.configBool(r.Context(), "ai.enabled", false)})
}

type aiAgentRequest struct {
	UserIDs         []int64 `json:"userIds"`
	Batch           string  `json:"batch"`
	Enabled         *bool   `json:"enabled"`
	ModelID         *int64  `json:"modelId"`
	Persona         *string `json:"persona"`
	DailyReplyLimit *int    `json:"dailyReplyLimit"`
}

// One endpoint for a single account and for a whole batch: operations usually
// switch a seeded batch on or off in one go.
func (a *App) adminUpdateAIAgents(w http.ResponseWriter, r *http.Request) {
	var req aiAgentRequest
	if decode(r, &req) != nil {
		fail(w, http.StatusBadRequest, 20001, "托管配置格式不正确")
		return
	}
	if req.Persona != nil && len([]rune(*req.Persona)) > 1000 {
		fail(w, http.StatusBadRequest, 20001, "人设描述最多 1000 字")
		return
	}
	if req.DailyReplyLimit != nil && (*req.DailyReplyLimit < 0 || *req.DailyReplyLimit > 10000) {
		fail(w, http.StatusBadRequest, 20001, "单账号每日回复上限必须在 0 到 10000 之间")
		return
	}
	if req.ModelID != nil && *req.ModelID > 0 {
		if _, err := a.loadAIModel(r.Context(), *req.ModelID); err != nil {
			fail(w, http.StatusBadRequest, 20001, "指定的模型不存在")
			return
		}
	}
	targets, err := a.resolveAIAgentTargets(r, req)
	if err != nil {
		fail(w, http.StatusBadRequest, 20001, err.Error())
		return
	}
	if len(targets) == 0 {
		fail(w, http.StatusBadRequest, 20001, "没有匹配的测试账号")
		return
	}
	enabled := true
	if req.Enabled != nil {
		enabled = *req.Enabled
	}
	modelID := int64(0)
	if req.ModelID != nil {
		modelID = *req.ModelID
	}
	persona := ""
	if req.Persona != nil {
		persona = strings.TrimSpace(*req.Persona)
	}
	limit := 0
	if req.DailyReplyLimit != nil {
		limit = *req.DailyReplyLimit
	}
	tx, err := a.db.BeginTx(r.Context(), nil)
	if err != nil {
		fail(w, http.StatusInternalServerError, 50001, "保存托管配置失败")
		return
	}
	defer func() { _ = tx.Rollback() }()
	for _, userID := range targets {
		if _, err = tx.ExecContext(r.Context(), `INSERT INTO ai_agents(user_id,model_id,persona,enabled,daily_reply_limit)
			VALUES(?,?,?,?,?)
			ON DUPLICATE KEY UPDATE model_id=VALUES(model_id),persona=VALUES(persona),enabled=VALUES(enabled),daily_reply_limit=VALUES(daily_reply_limit)`,
			userID, modelID, persona, btoi(enabled), limit); err != nil {
			fail(w, http.StatusInternalServerError, 50001, "保存托管配置失败")
			return
		}
	}
	if err = tx.Commit(); err != nil {
		fail(w, http.StatusInternalServerError, 50001, "保存托管配置失败")
		return
	}
	a.audit(r, "update", "ai_agent", 0, map[string]any{"count": len(targets), "enabled": enabled, "modelId": modelID, "batch": req.Batch})
	reply(w, map[string]any{"success": true, "count": len(targets)})
}

// Managed accounts must be test accounts; a batch is resolved server-side so a
// stale client list cannot bind a real user.
func (a *App) resolveAIAgentTargets(r *http.Request, req aiAgentRequest) ([]int64, error) {
	batch := strings.TrimSpace(req.Batch)
	if batch == "" && len(req.UserIDs) == 0 {
		return nil, fmt.Errorf("请选择测试账号或填写测试批次")
	}
	if len(req.UserIDs) > 500 {
		return nil, fmt.Errorf("单次最多操作 500 个账号")
	}
	query := `SELECT u.id FROM users u WHERE u.is_test=1 AND u.status=1 AND u.deleted_at IS NULL`
	args := []any{}
	if batch != "" {
		if len(batch) > 64 {
			return nil, fmt.Errorf("测试批次长度不能超过64位")
		}
		query += ` AND u.test_batch=?`
		args = append(args, batch)
	}
	if len(req.UserIDs) > 0 {
		placeholders := make([]string, 0, len(req.UserIDs))
		for _, userID := range req.UserIDs {
			placeholders = append(placeholders, "?")
			args = append(args, userID)
		}
		query += ` AND u.id IN (` + strings.Join(placeholders, ",") + `)`
	}
	rows, err := a.db.QueryContext(r.Context(), query, args...)
	if err != nil {
		return nil, fmt.Errorf("查询测试账号失败")
	}
	defer rows.Close()
	targets := []int64{}
	for rows.Next() {
		var userID int64
		if rows.Scan(&userID) == nil {
			targets = append(targets, userID)
		}
	}
	return targets, rows.Err()
}

// The queue is the first place to look when replies stop arriving.
func (a *App) adminAIReplyJobs(w http.ResponseWriter, r *http.Request) {
	page, size, offset := pagination(r)
	where, args := "", []any{}
	if status := strings.TrimSpace(r.URL.Query().Get("status")); status != "" {
		value, err := strconv.Atoi(status)
		if err != nil || value < 0 || value > 3 {
			fail(w, http.StatusBadRequest, 20001, "任务状态无效")
			return
		}
		where = " WHERE j.status=?"
		args = append(args, value)
	}
	var total int
	if err := a.db.QueryRowContext(r.Context(), `SELECT COUNT(*) FROM ai_reply_jobs j`+where, args...).Scan(&total); err != nil {
		fail(w, http.StatusInternalServerError, 50001, "查询回复任务失败")
		return
	}
	rows, err := a.db.QueryContext(r.Context(), `SELECT j.id,j.conversation_id,j.agent_user_id,COALESCE(p.nickname,''),j.status,j.attempts,j.run_after,j.last_error,j.created_at
		FROM ai_reply_jobs j LEFT JOIN user_profiles p ON p.user_id=j.agent_user_id`+where+` ORDER BY j.id DESC LIMIT ? OFFSET ?`,
		append(args, size, offset)...)
	if err != nil {
		fail(w, http.StatusInternalServerError, 50001, "查询回复任务失败")
		return
	}
	defer rows.Close()
	items := []map[string]any{}
	for rows.Next() {
		var id, conversationID, agentUserID int64
		var nickname, lastError string
		var status, attempts int
		var runAfter, createdAt sql.NullTime
		if rows.Scan(&id, &conversationID, &agentUserID, &nickname, &status, &attempts, &runAfter, &lastError, &createdAt) != nil {
			continue
		}
		item := map[string]any{
			"id": id, "conversationId": conversationID, "agentUserId": agentUserID, "nickname": nickname,
			"status": status, "attempts": attempts, "lastError": lastError,
		}
		if runAfter.Valid {
			item["runAfter"] = runAfter.Time.Format("2006-01-02 15:04:05")
		}
		if createdAt.Valid {
			item["createdAt"] = createdAt.Time.Format("2006-01-02 15:04:05")
		}
		items = append(items, item)
	}
	reply(w, map[string]any{"items": items, "page": page, "size": size, "total": total})
}