package casbin

import (
	"strings"

	"github.com/casbin/casbin/v2"
	"github.com/casbin/casbin/v2/model"
	gormadapter "github.com/casbin/gorm-adapter/v3"
	"gorm.io/driver/mysql"
	"gorm.io/gorm"
)

const modelText = `
[request_definition]
r = sub, obj, act

[policy_definition]
p = sub, obj, act

[role_definition]
g = _, _

[policy_effect]
e = some(where (p.eft == allow))

[matchers]
m = g(r.sub, p.sub) && keyMatch2(r.obj, p.obj) && (r.act == p.act || p.act == "*")
`

func NewEnforcer(dsn string) (*casbin.Enforcer, error) {
	db, err := gorm.Open(mysql.Open(dsn), &gorm.Config{})
	if err != nil {
		return nil, err
	}

	adapter, err := gormadapter.NewAdapterByDB(db)
	if err != nil {
		return nil, err
	}

	m, err := model.NewModelFromString(modelText)
	if err != nil {
		return nil, err
	}

	enforcer, err := casbin.NewEnforcer(m, adapter)
	if err != nil {
		return nil, err
	}

	if err := enforcer.LoadPolicy(); err != nil {
		return nil, err
	}

	return enforcer, nil
}

func CheckPermission(enforcer *casbin.Enforcer, roleKey, path, method string) bool {
	method = strings.ToUpper(method)
	ok, err := enforcer.Enforce(roleKey, path, method)
	if err != nil {
		return false
	}
	return ok
}