package middleware

import (
	"errors"
	"fmt"
	"ims/app/models"
	"ims/util/db"
	"ims/util/jwt"
	"ims/util/rdb"

	"github.com/jinzhu/inflection"
	"github.com/redis/go-redis/v9"
	"golang.org/x/sync/singleflight"
	"zestack.dev/log"
	"zestack.dev/slim"
)

var sfg singleflight.Group

type JWTExtra struct {
	AccountID  uint `redis:"account"`
	EmployeeID uint `redis:"employee"`
	TenantID   uint `redis:"tenant"`

	Account  *models.Account
	Employee *models.Employee
	Tenant   *models.Tenant
}

func Auth(withTenant, anonymously bool) slim.MiddlewareFunc {
	return jwt.Auth(jwt.AuthConfig{
		Skipper: func(c slim.Context) bool {
			if c.RouteMatchType() == slim.RouteMatchUnknown {
				panic("unknown route")
			}
			switch c.RouteInfo().Name() {
			case "login":
				return true
			default:
				return false
			}
		},
		Anonymously: anonymously,
		Claims: func(c slim.Context, token string, _ *jwt.Claims) error {
			var extra JWTExtra
			if err := extra.load(c, token); err != nil {
				return err
			}
			// 针对租户，如果加载失败，说明没有权限
			if withTenant && (extra.Tenant == nil || extra.Employee == nil) {
				return jwt.ErrForbidden
			}

			// // 如果租户数据没有初始化，那就只能访问有限的几个页面，
			// // 比如基本设置、初始化等。
			// if withTenant && !tenant.IsReady() {
			// 	return c.Redirect(http.StatusMovedPermanently, "/tenant/init")
			// }

			return nil
		},
	})
}

func (e *JWTExtra) load(c slim.Context, token string) error {
	// 加载额外信息
	if err := rdb.Redis().HGetAll(c, "jwt:"+token).Scan(e); err != nil {
		return err
	}
	// 加载用户信息
	if err := e.loadAccount(c); err != nil {
		return err
	}
	// 加载员工信息
	if err := e.loadEmployee(c); err != nil {
		return err
	}
	// 加载租户信息
	if err := e.loadTenant(c); err != nil {
		return err
	}
	return nil
}

func (e *JWTExtra) loadAccount(c slim.Context) error {
	var account models.Account
	err := e.loadModel(c, "account", e.AccountID, &account)
	if err != nil {
		return err
	}
	e.Account = &account
	return nil
}

func (e *JWTExtra) loadEmployee(c slim.Context) error {
	if e.EmployeeID == 0 {
		return nil
	}
	var employee models.Employee
	err := e.loadModel(c, "employee", e.EmployeeID, &employee)
	if err != nil {
		return err
	}
	e.Employee = &employee
	return nil
}

func (e *JWTExtra) loadTenant(c slim.Context) error {
	if e.TenantID == 0 {
		return nil
	}
	var tenant models.Tenant
	err := e.loadModel(c, "tenant", e.TenantID, &tenant)
	if err != nil {
		return err
	}
	e.Tenant = &tenant
	return nil
}

func (e *JWTExtra) loadModel(c slim.Context, label string, id uint, val any) error {
	client := rdb.Redis()
	key := fmt.Sprintf("%s:%d", inflection.Plural(label), id)
	_, err, _ := sfg.Do(key, func() (any, error) {
		// 加载 Redis 中的数据
		err := client.HGetAll(c, key).Scan(val)
		if err == nil {
			return nil, nil
		}
		if !errors.Is(err, redis.Nil) {
			return nil, err
		}
		// 加载数据库中的数据
		err = db.Engine().First(val, id).Error
		if err == nil && val != nil {
			err = client.HSet(c, key, val).Err()
			if err != nil {
				log.Error("failed to cache "+label, "error", err, "id", id)
			}
		}
		return nil, err
	})
	if err != nil {
		return err
	}
	c.Set("jwt:"+label, val)
	return nil
}