package server

import (
	"encoding/json"
	"errors"
	"github.com/gin-gonic/gin"
	"github.com/google/uuid"
	"perler-beads-server/internal/domain"
	"time"
)

func (s *Server) requestList(c *gin.Context) {
	if !need(c, "") {
		return
	}
	raw, e := s.list(c, "request")
	if e != nil {
		fail(c, e)
		return
	}
	out := []domain.Request{}
	u := user(c)
	for _, b := range raw {
		var v domain.Request
		if json.Unmarshal(b, &v) != nil {
			continue
		}
		if u.Role == "admin" || u.Role == "staff" {
			if v.StoreID != u.StoreID {
				continue
			}
		} else if v.UserID != u.ID {
			continue
		}
		out = append(out, v)
	}
	ok(c, out)
}
func (s *Server) requestCreate(c *gin.Context) {
	if !need(c, "") {
		return
	}
	var in struct {
		Kind      string `json:"kind"`
		Note      string `json:"note"`
		PatternID string `json:"patternId"`
		RequestID string `json:"requestId"`
	}
	if !bind(c, &in) {
		return
	}
	if _, e := uuid.Parse(in.RequestID); e != nil {
		fail(c, errors.New("requestId 必须为 UUID"))
		return
	}
	if in.Kind != "help" && in.Kind != "refill" && in.Kind != "ironing" && in.Kind != "print" || len(in.Note) > 2000 {
		fail(c, errors.New("服务类型或备注无效"))
		return
	}
	u := user(c)
	fingerprint := domain.Fingerprint(in.Kind, in.Note, in.PatternID)
	tx, e := s.DB.Begin(c)
	if e != nil {
		fail(c, e)
		return
	}
	defer rollback(tx) // Serialize same user's keys and visit changes while checking persistent idempotency.
	if _, e = tx.Exec(c, `SELECT pg_advisory_xact_lock(hashtextextended($1,0))`, u.ID); e != nil {
		fail(c, e)
		return
	}
	var existing []byte
	var oldHash string
	e = tx.QueryRow(c, `SELECT fingerprint,request_body FROM request_keys WHERE user_id=$1 AND request_id=$2`, u.ID, in.RequestID).Scan(&oldHash, &existing)
	if e == nil {
		if oldHash != fingerprint {
			reply(c, 409, "重复请求标识对应不同内容", nil)
			return
		}
		ok(c, json.RawMessage(existing))
		return
	}
	var visitBytes []byte
	if e = tx.QueryRow(c, `SELECT body FROM visits WHERE user_id=$1 FOR UPDATE`, u.ID).Scan(&visitBytes); e != nil {
		fail(c, errors.New("请先扫码到店"))
		return
	}
	var v domain.Visit
	if json.Unmarshal(visitBytes, &v) != nil || v.Status != "active" {
		fail(c, errors.New("请先扫码到店"))
		return
	}
	var tables []domain.Table
	if getTx(c, tx, "tables", v.StoreID, &tables) != nil {
		fail(c, errors.New("门店桌位不可用"))
		return
	}
	enabled := false
	for _, t := range tables {
		if t.Code == v.TableCode && t.Enabled {
			enabled = true
		}
	}
	if !enabled {
		fail(c, errors.New("桌位已停用，请重新扫码"))
		return
	}
	if in.Kind == "print" && in.PatternID == "" {
		fail(c, errors.New("打印需要图纸"))
		return
	}
	if in.PatternID != "" {
		var p domain.Pattern
		if getTx(c, tx, "pattern", in.PatternID, &p) != nil || !domain.CanRead(p, u) || p.StoreID != v.StoreID {
			reply(c, 401, "图纸无权限或不属于当前门店", nil)
			return
		}
	}
	now := time.Now().UTC().Format(time.RFC3339Nano)
	r := domain.Request{ID: uuid.NewString(), StoreID: v.StoreID, UserID: u.ID, TableCode: v.TableCode, Kind: in.Kind, Note: in.Note, PatternID: in.PatternID, Status: "pending", CreatedAt: now, UpdatedAt: now}
	b, _ := json.Marshal(r)
	if _, e = tx.Exec(c, `INSERT INTO documents(kind,id,store_id,owner_id,body) VALUES('request',$1,$2,$3,$4)`, r.ID, r.StoreID, r.UserID, b); e == nil {
		_, e = tx.Exec(c, `INSERT INTO request_keys VALUES($1,$2,$3,$4)`, u.ID, in.RequestID, fingerprint, b)
	}
	if e != nil {
		fail(c, e)
		return
	}
	if e = tx.Commit(c); e != nil {
		fail(c, e)
		return
	}
	s.notifyTasks(r.StoreID)
	ok(c, r)
}
func (s *Server) requestPatch(c *gin.Context) {
	if !need(c, "") {
		return
	}
	var in struct {
		Status string `json:"status"`
	}
	if !bind(c, &in) {
		return
	}
	tx, e := s.DB.Begin(c)
	if e != nil {
		fail(c, e)
		return
	}
	defer rollback(tx)
	var b []byte
	if e = tx.QueryRow(c, `SELECT body FROM documents WHERE kind='request' AND id=$1 FOR UPDATE`, c.Param("id")).Scan(&b); e != nil {
		reply(c, 404, "任务不存在", nil)
		return
	}
	var r domain.Request
	if json.Unmarshal(b, &r) != nil {
		fail(c, errors.New("任务数据无效"))
		return
	}
	u := user(c)
	staff := u.Role == "admin" || u.Role == "staff"
	if staff && r.StoreID != u.StoreID || !domain.Transition(u.Role, r.Status, in.Status, r.UserID == u.ID) {
		reply(c, 401, "无权进行此状态变更", nil)
		return
	}
	r.Status = in.Status
	r.UpdatedAt = time.Now().UTC().Format(time.RFC3339Nano)
	b, _ = json.Marshal(r)
	if _, e = tx.Exec(c, `UPDATE documents SET body=$1 WHERE kind='request' AND id=$2`, b, r.ID); e != nil {
		fail(c, e)
		return
	}
	if e = tx.Commit(c); e != nil {
		fail(c, e)
		return
	}
	s.notifyTasks(r.StoreID)
	ok(c, r)
}