LibLine: Allow the user to override (or add) keybinds in the config file

Author: https://github.com/alimpfard
Commit: https://github.com/SerenityOS/serenity/commit/5b9d563b4b9
Pull-request: https://github.com/SerenityOS/serenity/pull/3193

Libraries/LibLine/Editor.cpp

@@ -25,6 +25,7 @@
  */
 
 #include "Editor.h"
+#include <AK/GenericLexer.h>
 #include <AK/JsonObject.h>
 #include <AK/StringBuilder.h>
 #include <AK/Utf32View.h>
@@ -71,6 +72,52 @@ Configuration Configuration::from_config(const StringView& libname)
     else
         configuration.set(Configuration::OperationMode::Unset);
 
+    // Read keybinds.
+
+    for (auto& binding_key : config_file->keys("keybinds")) {
+        GenericLexer key_lexer(binding_key);
+        auto has_ctrl = false;
+        auto alt = false;
+        unsigned key = 0;
+
+        while (!key && !key_lexer.is_eof()) {
+            if (key_lexer.next_is("alt+")) {
+                alt = key_lexer.consume_specific("alt+");
+                continue;
+            }
+            if (key_lexer.next_is("^[")) {
+                alt = key_lexer.consume_specific("^[");
+                continue;
+            }
+            if (key_lexer.next_is("^")) {
+                has_ctrl = key_lexer.consume_specific("^");
+                continue;
+            }
+            if (key_lexer.next_is("ctrl+")) {
+                has_ctrl = key_lexer.consume_specific("ctrl+");
+                continue;
+            }
+            // FIXME: Support utf?
+            key = key_lexer.consume();
+        }
+
+        if (has_ctrl)
+            key = ctrl(key);
+
+        auto value = config_file->read_entry("keybinds", binding_key);
+        if (value.starts_with("internal:")) {
+            configuration.set(KeyBinding {
+                Key { key, alt ? Key::Alt : Key::None },
+                KeyBinding::Kind::InternalFunction,
+                value.substring(9, value.length() - 9) });
+        } else {
+            configuration.set(KeyBinding {
+                Key { key, alt ? Key::Alt : Key::None },
+                KeyBinding::Kind::Insertion,
+                value });
+        }
+    }
+
     return configuration;
 }
 
@@ -118,6 +165,9 @@ Editor::Editor(Configuration configuration)
     m_suggestion_display = make<XtermSuggestionDisplay>(m_num_lines, m_num_columns);
 
     set_default_keybinds();
+
+    for (auto& keybind : m_configuration.keybindings)
+        register_key_input_callback(keybind);
 }
 
 Editor::~Editor()

Libraries/LibLine/Editor.h

@@ -53,38 +53,6 @@
 
 namespace Line {
 
-struct Configuration {
-    enum RefreshBehaviour {
-        Lazy,
-        Eager,
-    };
-    enum OperationMode {
-        Unset,
-        Full,
-        NoEscapeSequences,
-        NonInteractive,
-    };
-
-    Configuration()
-    {
-    }
-
-    template<typename Arg, typename... Rest>
-    Configuration(Arg arg, Rest... rest)
-        : Configuration(rest...)
-    {
-        set(arg);
-    }
-
-    void set(RefreshBehaviour refresh) { refresh_behaviour = refresh; }
-    void set(OperationMode mode) { operation_mode = mode; }
-
-    static Configuration from_config(const StringView& libname = "line");
-
-    RefreshBehaviour refresh_behaviour { RefreshBehaviour::Lazy };
-    OperationMode operation_mode { OperationMode::Unset };
-};
-
 struct Key {
     enum Modifier : int {
         None = 0,
@@ -119,6 +87,40 @@ struct KeyBinding {
     String binding;
 };
 
+struct Configuration {
+    enum RefreshBehaviour {
+        Lazy,
+        Eager,
+    };
+    enum OperationMode {
+        Unset,
+        Full,
+        NoEscapeSequences,
+        NonInteractive,
+    };
+
+    Configuration()
+    {
+    }
+
+    template<typename Arg, typename... Rest>
+    Configuration(Arg arg, Rest... rest)
+        : Configuration(rest...)
+    {
+        set(arg);
+    }
+
+    void set(RefreshBehaviour refresh) { refresh_behaviour = refresh; }
+    void set(OperationMode mode) { operation_mode = mode; }
+    void set(const KeyBinding& binding) { keybindings.append(binding); }
+
+    static Configuration from_config(const StringView& libname = "line");
+
+    RefreshBehaviour refresh_behaviour { RefreshBehaviour::Lazy };
+    OperationMode operation_mode { OperationMode::Unset };
+    Vector<KeyBinding> keybindings;
+};
+
 #define ENUMERATE_EDITOR_INTERNAL_FUNCTIONS(M) \
     M(clear_screen)                            \
     M(cursor_left_character)                   \