jcs.org
Serenity Operating System
1/*
2 * Copyright (c) 2021, sin-ack <sin-ack@protonmail.com>
3 * Copyright (c) 2022, the SerenityOS developers.
4 *
5 * SPDX-License-Identifier: BSD-2-Clause
6 */
7
8#pragma once
9
10#include <AK/RefCounted.h>
11#include <AK/WeakPtr.h>
12#include <LibGUI/Model.h>
13#include <LibGUI/ModelIndex.h>
14
15namespace GUI {
16
17/// A PersistentHandle is an internal data structure used to keep track of the
18/// target of multiple PersistentModelIndex instances.
19class PersistentHandle : public Weakable<PersistentHandle> {
20 friend Model;
21 friend PersistentModelIndex;
22 friend AK::Traits<GUI::PersistentModelIndex>;
23
24 PersistentHandle(ModelIndex const& index)
25 : m_index(index)
26 {
27 }
28
29 ModelIndex m_index;
30};
31
32class PersistentModelIndex {
33public:
34 PersistentModelIndex() = default;
35 PersistentModelIndex(ModelIndex const&);
36 PersistentModelIndex(PersistentModelIndex const&) = default;
37 PersistentModelIndex(PersistentModelIndex&&) = default;
38
39 PersistentModelIndex& operator=(PersistentModelIndex const&) = default;
40 PersistentModelIndex& operator=(PersistentModelIndex&&) = default;
41
42 bool is_valid() const { return has_valid_handle() && m_handle->m_index.is_valid(); }
43 bool has_valid_handle() const { return !m_handle.is_null(); }
44
45 int row() const;
46 int column() const;
47 PersistentModelIndex parent() const;
48 PersistentModelIndex sibling_at_column(int column) const;
49 Variant data(ModelRole = ModelRole::Display) const;
50
51 void* internal_data() const
52 {
53 if (has_valid_handle())
54 return m_handle->m_index.internal_data();
55 else
56 return nullptr;
57 }
58
59 operator ModelIndex() const;
60 bool operator==(PersistentModelIndex const&) const;
61 bool operator!=(PersistentModelIndex const&) const;
62 bool operator==(ModelIndex const&) const;
63 bool operator!=(ModelIndex const&) const;
64
65private:
66 friend AK::Traits<GUI::PersistentModelIndex>;
67
68 WeakPtr<PersistentHandle> m_handle;
69};
70
71}
72
73namespace AK {
74
75template<>
76struct Formatter<GUI::PersistentModelIndex> : Formatter<FormatString> {
77 ErrorOr<void> format(FormatBuilder& builder, GUI::PersistentModelIndex const& value)
78 {
79 return Formatter<FormatString>::format(builder, "PersistentModelIndex({},{},{})"sv, value.row(), value.column(), value.internal_data());
80 }
81};
82
83template<>
84struct Traits<GUI::PersistentModelIndex> : public GenericTraits<GUI::PersistentModelIndex> {
85 static unsigned hash(const GUI::PersistentModelIndex& index)
86 {
87 if (index.has_valid_handle())
88 return Traits<GUI::ModelIndex>::hash(index.m_handle->m_index);
89 return 0;
90 }
91};
92
93}