package api

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

type YMTUsersAPI struct {
	ymt *sql.DB
}

func YMTUsersHandler(ymt *sql.DB) http.Handler {
	api := &YMTUsersAPI{ymt: ymt}
	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		p := strings.TrimPrefix(r.URL.Path, "/api/ymt/users")
		if r.Method == http.MethodGet && p == "" {
			api.list(w, r)
			return
		}
		w.WriteHeader(http.StatusNotFound)
	})
}

func (a *YMTUsersAPI) list(w http.ResponseWriter, r *http.Request) {
	limitStr := r.URL.Query().Get("limit")
	limit := 2000
	if limitStr != "" {
		if n, err := strconv.Atoi(limitStr); err == nil && n > 0 && n <= 10000 {
			limit = n
		}
	}
	sql1 := "SELECT id, name FROM user WHERE id IS NOT NULL"
	args := []interface{}{}
	sql1 += " ORDER BY id ASC LIMIT ?"
	args = append(args, limit)
	rows, err := a.ymt.Query(sql1, args...)
	if err != nil {
		fail(w, r, http.StatusInternalServerError, err.Error())
		return
	}
	defer rows.Close()

	out := []map[string]interface{}{}
	used := map[int64]struct{}{}
	for rows.Next() {
		var id sql.NullInt64
		var name sql.NullString
		if err := rows.Scan(&id, &name); err != nil {
			continue
		}
		if !id.Valid {
			continue
		}
		n := strings.TrimSpace(name.String)
		if n == "" {
			n = strconv.FormatInt(id.Int64, 10)
		}
		display := fmt.Sprintf("%s（%d）", n, id.Int64)

		out = append(out, map[string]interface{}{"id": id.Int64, "name": display})
	}
	ok(w, r, out)
}