package handler

import (
	"encoding/json"
	"net/http"

	"aijianzhan/platform/internal/authx"
	"aijianzhan/platform/internal/dbsync"
	"aijianzhan/platform/internal/svc"

	"github.com/zeromicro/go-zero/rest/httpx"
	"github.com/zeromicro/go-zero/rest/pathvar"
)

// agent 同步只读白名单 + 推远程 A（形态 B）；需 JWT 含「数据同步」权限（人类管理员或智能体均可）。

func agentSyncWhitelistHandler(svcCtx *svc.ServiceContext) http.HandlerFunc {
	return func(w http.ResponseWriter, r *http.Request) {
		if !requireDBSync(svcCtx, w) {
			return
		}
		ch, err := svcCtx.DBSync.Store().GetChannelForTenant(pathvar.Vars(r)["id"], syncTenantID(r))
		if err != nil {
			authx.WriteError(w, http.StatusNotFound, err.Error())
			return
		}
		tables := uniqueStringSlice(ch.Local.Tables, ch.Remote.Tables)
		httpx.OkJson(w, map[string]any{
			"channel_id":      ch.ID,
			"name":            ch.Name,
			"enabled":         ch.Enabled,
			"direction":       ch.Direction,
			"conflict_policy": ch.ConflictPolicy,
			"tables":          tables,
			"pk_columns":      ch.PKColumns,
			"hint":            "本机 agent 缓存此表白名单；仅白名单表走 local_dbsync",
		})
	}
}

func agentSyncPushHandler(svcCtx *svc.ServiceContext) http.HandlerFunc {
	return func(w http.ResponseWriter, r *http.Request) {
		if !requireDBSync(svcCtx, w) {
			return
		}
		ch, err := svcCtx.DBSync.Store().GetChannelForTenant(pathvar.Vars(r)["id"], syncTenantID(r))
		if err != nil {
			authx.WriteError(w, http.StatusNotFound, err.Error())
			return
		}
		var item dbsync.PushItem
		if err := json.NewDecoder(r.Body).Decode(&item); err != nil {
			authx.WriteError(w, http.StatusBadRequest, err.Error())
			return
		}
		res, err := dbsync.PushToRemote(r.Context(), ch, svcCtx.DBSync.Store(), item)
		if err != nil {
			authx.WriteError(w, http.StatusBadRequest, err.Error())
			return
		}
		httpx.OkJson(w, map[string]any{"success": true, "result": res})
	}
}

func agentSyncPushBatchHandler(svcCtx *svc.ServiceContext) http.HandlerFunc {
	return func(w http.ResponseWriter, r *http.Request) {
		if !requireDBSync(svcCtx, w) {
			return
		}
		ch, err := svcCtx.DBSync.Store().GetChannelForTenant(pathvar.Vars(r)["id"], syncTenantID(r))
		if err != nil {
			authx.WriteError(w, http.StatusNotFound, err.Error())
			return
		}
		var body struct {
			Items []dbsync.PushItem `json:"items"`
		}
		if err := json.NewDecoder(r.Body).Decode(&body); err != nil {
			authx.WriteError(w, http.StatusBadRequest, err.Error())
			return
		}
		if len(body.Items) == 0 {
			authx.WriteError(w, http.StatusBadRequest, "items required")
			return
		}
		if len(body.Items) > 100 {
			authx.WriteError(w, http.StatusBadRequest, "items limit 100")
			return
		}
		results, err := dbsync.PushBatchToRemote(r.Context(), ch, svcCtx.DBSync.Store(), body.Items)
		if err != nil {
			httpx.OkJson(w, map[string]any{
				"success": false,
				"error":   err.Error(),
				"results": results,
			})
			return
		}
		httpx.OkJson(w, map[string]any{"success": true, "results": results})
	}
}

func uniqueStringSlice(a, b []string) []string {
	seen := map[string]struct{}{}
	var out []string
	for _, xs := range [][]string{a, b} {
		for _, s := range xs {
			if s == "" {
				continue
			}
			if _, ok := seen[s]; ok {
				continue
			}
			seen[s] = struct{}{}
			out = append(out, s)
		}
	}
	return out
}