package app

import (
	"encoding/json"
	"errors"
	"fmt"
	"net/http"
	"strings"
	"time"

	"github.com/go-sql-driver/mysql"
)

type adminCreateUserRequest struct {
	Phone    string `json:"phone"`
	Password string `json:"password"`
	Nickname string `json:"nickname"`
	Gender   int    `json:"gender"`
	City     string `json:"city"`
	Bio      string `json:"bio"`
}

// Administrator provisioning uses the same credentials as public registration,
// but never creates a login session or marks the phone/identity as verified.
func (a *App) adminCreateUser(w http.ResponseWriter, r *http.Request) {
	var req adminCreateUserRequest
	if decode(r, &req) != nil {
		fail(w, http.StatusBadRequest, 20001, "用户资料格式不正确")
		return
	}
	req.Phone = strings.TrimSpace(req.Phone)
	req.Nickname = strings.TrimSpace(req.Nickname)
	req.City = strings.TrimSpace(req.City)
	req.Bio = strings.TrimSpace(req.Bio)
	if !validPhone(req.Phone) {
		fail(w, http.StatusBadRequest, 20001, "请输入有效的中国大陆手机号")
		return
	}
	if !validUserPassword(req.Password) {
		fail(w, http.StatusBadRequest, 20001, passwordRule)
		return
	}
	if req.Nickname == "" || len([]rune(req.Nickname)) > 50 || req.Gender < 0 || req.Gender > 2 || len([]rune(req.City)) > 50 || len([]rune(req.Bio)) > 500 {
		fail(w, http.StatusBadRequest, 20001, "昵称须为 1–50 字，城市最多 50 字，简介最多 500 字，性别须为有效选项")
		return
	}
	passwordHash, err := hashPassword(req.Password)
	if err != nil {
		fail(w, http.StatusInternalServerError, 50001, "创建用户失败")
		return
	}
	phoneCipher, err := a.encryptPhone(req.Phone)
	if err != nil {
		fail(w, http.StatusInternalServerError, 50001, "加密手机号失败")
		return
	}
	tx, err := a.db.BeginTx(r.Context(), nil)
	if err != nil {
		fail(w, http.StatusInternalServerError, 50001, "创建用户失败")
		return
	}
	defer func() { _ = tx.Rollback() }()
	publicID := fmt.Sprintf("XY%d%s", time.Now().UnixMilli(), randomToken()[:5])
	result, err := tx.ExecContext(r.Context(), `INSERT INTO users (public_id,country_code,phone_hash,phone_cipher,password_hash) VALUES (?,'+86',?,?,?)`, publicID, phoneHash(req.Phone), phoneCipher, passwordHash)
	if err != nil {
		var mysqlErr *mysql.MySQLError
		if errors.As(err, &mysqlErr) && mysqlErr.Number == 1062 && strings.Contains(mysqlErr.Message, "uk_users_phone_hash") {
			fail(w, http.StatusConflict, 20001, "该手机号已被使用，请勿重复创建")
		} else {
			fail(w, http.StatusInternalServerError, 50001, "创建用户失败，请稍后重试")
		}
		return
	}
	userID, err := result.LastInsertId()
	if err != nil {
		fail(w, http.StatusInternalServerError, 50001, "创建用户失败")
		return
	}
	if _, err = tx.ExecContext(r.Context(), `INSERT INTO user_profiles (user_id,nickname,gender,city_name,bio,profile_score) VALUES (?,?,?,?,?,30)`, userID, req.Nickname, req.Gender, req.City, req.Bio); err != nil {
		fail(w, http.StatusInternalServerError, 50001, "创建用户资料失败")
		return
	}
	if _, err = tx.ExecContext(r.Context(), `INSERT INTO user_privacy_settings (user_id) VALUES (?)`, userID); err != nil {
		fail(w, http.StatusInternalServerError, 50001, "初始化隐私设置失败")
		return
	}
	if _, err = tx.ExecContext(r.Context(), `INSERT INTO user_notification_settings (user_id) VALUES (?)`, userID); err != nil {
		fail(w, http.StatusInternalServerError, 50001, "初始化通知设置失败")
		return
	}
	// Audit and account creation succeed together. Do not store the request body:
	// it contains the initial password and the full phone number.
	auditData, _ := json.Marshal(map[string]any{"publicId": publicID, "nickname": req.Nickname, "source": "admin"})
	if _, err = tx.ExecContext(r.Context(), `INSERT INTO admin_audit_logs(admin_user_id,action,target_type,target_id,request_data,ip) VALUES (?,'create_user','user',?,?,?)`, current(r).ID, userID, auditData, clientIP(r)); err != nil {
		fail(w, http.StatusInternalServerError, 50001, "记录创建日志失败，用户未创建")
		return
	}
	if err = tx.Commit(); err != nil {
		fail(w, http.StatusInternalServerError, 50001, "创建用户失败")
		return
	}
	reply(w, map[string]any{"id": userID, "publicId": publicID})
}