Improve chat history (#12975)

1 files changed, 20 insertions, 4 deletions

diff --git a/src/chat.h b/src/chat.h
index fc080f64b..280701d47 100644
--- a/src/chat.h
+++ b/src/chat.h
@@ -25,6 +25,7 @@ with this program; if not, write to the Free Software Foundation, Inc.,
 
 #include "irrlichttypes.h"
 #include "util/enriched_string.h"
+#include "util/Optional.h"
 #include "settings.h"
 
 // Chat console related classes
@@ -172,10 +173,10 @@ public:
 	void addToHistory(const std::wstring &line);
 
 	// Get current line
-	std::wstring getLine() const { return m_line; }
+	std::wstring getLine() const { return getLineRef(); }
 
 	// Get section of line that is currently selected
-	std::wstring getSelection() const { return m_line.substr(m_cursor, m_cursor_len); }
+	std::wstring getSelection() const { return getLineRef().substr(m_cursor, m_cursor_len); }
 
 	// Clear the current line
 	void clear();
@@ -233,18 +234,33 @@ public:
 	void cursorOperation(CursorOp op, CursorOpDir dir, CursorOpScope scope);
 
 protected:
+	const std::wstring &getLineRef() const;
+
+	std::wstring &makeLineRef();
+
 	// set m_view to ensure that 0 <= m_view <= m_cursor < m_view + m_cols
 	// if line can be fully shown, set m_view to zero
 	// else, also ensure m_view <= m_line.size() + 1 - m_cols
 	void clampView();
 
 private:
+	struct HistoryEntry {
+		std::wstring line;
+		// If line is edited, saved holds the unedited version.
+		Optional<std::wstring> saved;
+
+		HistoryEntry(const std::wstring &line): line(line) {}
+
+		bool operator==(const HistoryEntry &other);
+		bool operator!=(const HistoryEntry &other) { return !(*this == other); }
+	};
+
 	// Prompt prefix
 	std::wstring m_prompt = L"";
-	// Currently edited line
+	// Non-historical edited line
 	std::wstring m_line = L"";
 	// History buffer
-	std::vector<std::wstring> m_history;
+	std::vector<HistoryEntry> m_history;
 	// History index (0 <= m_history_index <= m_history.size())
 	u32 m_history_index = 0;
 	// Maximum number of history entries