package room

import (
	"time"
)

type RoomMember struct {
	RoomName    string       `json:"room_name"`
	RoomID      string       `json:"room_id"`
	UserID      string       `json:"user_id"`
	Username    string       `json:"username"`
	Role        RoomRole     `json:"role"`
	Status      MemberStatus `json:"status"`
	AddedPerms  uint64       `json:"added_permissions"`
	RemovedPerms uint64      `json:"removed_permissions"`
	AdminAdded  uint64       `json:"admin_added_permissions"`
	AdminRemoved uint64      `json:"admin_removed_permissions"`
	JoinedAt    time.Time    `json:"joined_at"`
	Version     int64        `json:"version"`
}

func NewMember(room, username string, role RoomRole) *RoomMember {
	return &RoomMember{
		RoomName: room,
		Username: username,
		UserID:   username,
		Role:     role,
		Status:   MemberActive,
		JoinedAt: time.Now(),
		Version:  1,
	}
}

func (m *RoomMember) EffectivePermissions(settings *RoomSettings) PermissionSet {
	if m.Role == RoleCreator {
		return PermAll
	}
	base := m.basePermissions(settings)
	switch m.Role {
	case RoleAdmin:
		res := base
		res |= PermissionSet(m.AdminAdded)
		res &^= PermissionSet(m.AdminRemoved)
		return res
	case RoleMember:
		res := base
		res |= PermissionSet(m.AddedPerms)
		res &^= PermissionSet(m.RemovedPerms)
		return res
	case RoleGuest:
		res := base & PermGuestAssignable
		added := PermissionSet(m.AddedPerms) & PermGuestAssignable
		removed := PermissionSet(m.RemovedPerms) & PermGuestAssignable
		res |= added
		res &^= removed
		return res
	default:
		return base
	}
}

func (m *RoomMember) basePermissions(settings *RoomSettings) PermissionSet {
	if settings == nil {
		return DefaultForRole(m.Role)
	}
	switch m.Role {
	case RoleAdmin:
		return settings.AdminPermissions()
	case RoleMember:
		return settings.MemberPermissions()
	case RoleGuest:
		return settings.GuestPermissions()
	case RoleCreator:
		return PermAll
	default:
		return DefaultForRole(m.Role)
	}
}

func (m *RoomMember) HasPermission(p RoomPermission, settings *RoomSettings) bool {
	return m.EffectivePermissions(settings).Has(p)
}

func (m *RoomMember) CanGrant(target *RoomMember, perm RoomPermission, settings *RoomSettings) bool {
	if !m.HasPermission(PermManagePermissions, settings) {
		return false
	}
	if !m.Role.CanManage(target.Role) {
		return false
	}
	if m.Role == RoleAdmin && perm == PermDeleteRoom {
		return false
	}
	return true
}