feat(console): rework (selectable/copyable log text entries)

code/components/conhost-server/component.lua

@@ -7,13 +7,16 @@ return function()
 		includedirs {
 			"components/conhost-v2/include/",
 			"components/conhost-v2/src/",
+			"../vendor/range-v3/include/",
+			"../vendor/utfcpp/source",
 		}
 
 		files {
 			"components/conhost-v2/src/ConsoleHost.cpp",
 			"components/conhost-v2/src/ConsoleHostGui.cpp",
 			"components/conhost-v2/src/DevGui.cpp",
 			"components/conhost-v2/src/backends/**.cpp",
+			"components/conhost-v2/src/Textselect.cpp",
 		}
 	end
 end

code/components/conhost-v2/component.lua

@@ -17,6 +17,8 @@ return function()
 		includedirs { '../vendor/vulkan-headers/include/' }
 	end
 
+	includedirs { "../vendor/range-v3/include/", "../vendor/utfcpp/source" }
+
 	filter {}
 
 	links { 'delayimp' }

code/components/conhost-v2/include/Textselect.hpp

@@ -0,0 +1,83 @@
+// Copyright 2024 Aidan Sun and the ImGuiTextSelect contributors
+// SPDX-License-Identifier: MIT
+
+#pragma once
+
+#include <cstddef>
+#include <functional>
+
+#include <imgui.h>
+
+// Manages text selection in a GUI window.
+// This class only works if the window only has text, and line wrapping is not supported.
+// The window should also have the "NoMove" flag set so mouse drags can be used to select text.
+class TextSelect {
+    // Cursor position in the window.
+    struct CursorPos {
+        std::size_t x = std::string_view::npos; // X index of character
+        std::size_t y = std::string_view::npos; // Y index of character
+
+        // Checks if this position is invalid.
+        bool isInvalid() const {
+            // Invalid cursor positions are indicated by std::string::npos
+            return x == std::string_view::npos || y == std::string_view::npos;
+        }
+    };
+
+    // Text selection in the window.
+    struct Selection {
+        std::size_t startX;
+        std::size_t startY;
+        std::size_t endX;
+        std::size_t endY;
+    };
+
+    // Selection bounds
+    // In a selection, the start and end positions may not be in order (the user can click and drag left/up which
+    // reverses start and end).
+    CursorPos selectStart;
+    CursorPos selectEnd;
+
+    // Accessor functions to get line information
+    // This class only knows about line numbers so it must be provided with functions that give it text data.
+    std::function<std::string_view(std::size_t)> getLineAtIdx; // Gets the string given a line number
+    std::function<std::size_t()> getNumLines; // Gets the total number of lines
+    std::function<float(std::size_t)> getTextOffset; // Gets the offset of the text
+
+    // Gets the user selection. Start and end are guaranteed to be in order.
+    Selection getSelection();
+
+    // Processes mouse down (click/drag) events.
+    void handleMouseDown(const ImVec2& cursorPosStart);
+
+    // Processes scrolling events.
+    static void handleScrolling();
+
+    // Draws the text selection rectangle in the window.
+    void drawSelection(const ImVec2& cursorPosStart);
+
+public:
+    // Sets the text accessor functions.
+    // getLineAtIdx: Function taking a std::size_t (line number) and returning the string in that line
+    // getNumLines: Function returning a std::size_t (total number of lines of text)
+    // getTextOffset: Function taking a std::size_t (line number) and returning the offset of the text as a float
+    template <class T, class U, class V>
+    TextSelect(const T& getLineAtIdx, const U& getNumLines, const V& getTextOffset) : getLineAtIdx(getLineAtIdx), getNumLines(getNumLines), getTextOffset(getTextOffset) {}
+
+    template <class T, class U>
+    TextSelect(const T& getLineAtIdx, const U& getNumLines) : TextSelect(getLineAtIdx, getNumLines, []() { return 0.0f; }) {}
+
+    // Checks if there is an active selection in the text.
+    bool hasSelection() const {
+        return !selectStart.isInvalid() && !selectEnd.isInvalid();
+    }
+
+    // Copies the selected text to the clipboard.
+    void copy();
+
+    // Selects all text in the window.
+    void selectAll();
+
+    // Draws the text selection rectangle and handles user input.
+    void update(std::size_t itemOffset = 0);
+};