From cb489d42d522f7515c870942bcaa8f0f3dea3f35 Mon Sep 17 00:00:00 2001 From: magiblot Date: Fri, 7 Aug 2020 01:59:33 +0200 Subject: [PATCH] TInputLine: add Unicode support This is great news! --- README.md | 6 ++-- include/tvision/dialogs.h | 2 ++ include/tvision/ttext.h | 59 ++++++++++++++++++++++++++++++ source/tvision/tinputli.cpp | 72 ++++++++++++++++++++++--------------- 4 files changed, 106 insertions(+), 33 deletions(-) diff --git a/README.md b/README.md index daadbee8..6db3cd10 100644 --- a/README.md +++ b/README.md @@ -255,8 +255,6 @@ KeyDownEvent { ``` So, in short: views designed without Unicode input in mind will continue to work exactly as they did before, and views which want to be Unicode-aware will have no issues in being so. -For the time being, none of the builtin views have been modified to support Unicode input. - ## Displaying Unicode text The original design of Turbo Vision uses 16 bits to represent a *screen cell*—8 bit for a character and 8 bit for [BIOS color attributes](https://en.wikipedia.org/wiki/BIOS_color_attributes). @@ -380,7 +378,7 @@ Here is what it looks like: Support for creating Unicode-aware views is in place, but most of the views that are part of the original Turbo Vision library have not been adapted to handle Unicode. -* At least `TFrame`, `THistoryViewer`, `TListViewer`, `TInputLine` and `TMenuBox` are able to display Unicode text properly. +* At least `TFrame`, `THistoryViewer`, `TListViewer` and `TMenuBox` are able to display Unicode text properly. * Automatic shortcuts in `TMenuBox` won't work with Unicode text, as shortcuts are still compared against `event.keyDown.charScan.charCode`. -* `TInputLine` can display but not process Unicode text, as it still believes that every byte is one column wide. This can lead to inconsistencies, because some non-ASCII characters can be represented in the active codepage. For instance, if using CP437, it is possible to type `ç` into a `TInputLine`, but it will be a narrow character instead of a UTF-8 sequence. If you manage to place UTF-8 text in a `TInputLine` (e.g. by selecting a file in a `TFileDialog`), the caret will appear to be out of sync as its position is measured assuming a single-byte encoding. +* `TInputLine` can display and process Unicode text. * `TEditor` assumes a single-byte encoding both when handling input events and when displaying text. So it won't display UTF-8 but at least it has a consistent behaviour. diff --git a/include/tvision/dialogs.h b/include/tvision/dialogs.h index edf32ac3..45d787b9 100644 --- a/include/tvision/dialogs.h +++ b/include/tvision/dialogs.h @@ -185,7 +185,9 @@ class TInputLine : public TView Boolean canScroll( int delta ); int mouseDelta( TEvent& event ); int mousePos( TEvent& event ); + int displayedPos( int pos ); void deleteSelect(); + void deleteCurrent(); void adjustSelectBlock(); void saveState(); void restoreState(); diff --git a/include/tvision/ttext.h b/include/tvision/ttext.h index e469ad25..429ae13c 100644 --- a/include/tvision/ttext.h +++ b/include/tvision/ttext.h @@ -114,6 +114,10 @@ class TText { public: + static size_t next(TStringView text); + static size_t prev(TStringView text, size_t index); + static size_t wseek(TStringView text, int count); + #ifndef __BORLANDC__ static void eat(TScreenCell *cell, size_t n, size_t &width, std::string_view src, size_t &bytes); static void next(std::string_view src, size_t &bytes, size_t &width); @@ -122,6 +126,61 @@ class TText { }; +#ifdef __BORLANDC__ + +inline size_t TText::next(TStringView text) +{ + return text.size() ? 1 : 0; +} + +inline size_t TText::prev(TStringView text, size_t index) +{ + return index ? 1 : 0; +} + +inline size_t TText::wseek(TStringView text, int count) +{ + return count > 0 ? count : 0; +} + +#else + +inline size_t TText::next(TStringView text) +{ + if (text.size()) { + std::mbstate_t state {}; + int64_t len = std::mbrtowc(nullptr, text.data(), text.size(), &state); + return len <= 1 ? 1 : len; + } + return 0; +} + +inline size_t TText::prev(TStringView text, size_t index) +{ + if (index) { + // Try reading backwards character by character, until a valid + // character is found. This tolerates invalid characters. + size_t lead = std::min(index, 4); + for (size_t i = 1; i <= lead; ++i) { + std::mbstate_t state {}; + int64_t size = std::mbrtowc(nullptr, &text[index - i], i, &state); + if (size > 0) + return size == i ? i : 1; + } + return 1; + } + return 0; +} + +inline size_t TText::wseek(TStringView text, int count) +{ + size_t index = 0, remainder = 0; + wseek(text, index, remainder, count); + return index; +} + +#endif + #ifndef __BORLANDC__ inline void TText::eat( TScreenCell *cell, size_t n, size_t &width, diff --git a/source/tvision/tinputli.cpp b/source/tvision/tinputli.cpp index 8af2322d..33fe9bf0 100644 --- a/source/tvision/tinputli.cpp +++ b/source/tvision/tinputli.cpp @@ -111,15 +111,15 @@ void TInputLine::draw() { if( canScroll(-1) ) b.moveChar( 0, leftArrow, getColor(4), 1 ); - l = selStart - firstPos; - r = selEnd - firstPos; + l = displayedPos(selStart) - firstPos; + r = displayedPos(selEnd) - firstPos; l = max( 0, l ); r = min( size.x - 2, r ); if (l < r) b.moveChar( l+1, 0, getColor(3), r - l ); } writeLine( 0, 0, size.x, size.y, b ); - setCursor( curPos-firstPos+1, 0); + setCursor( displayedPos(curPos)-firstPos+1, 0); } void TInputLine::getData( void *rec ) @@ -153,8 +153,14 @@ int TInputLine::mousePos( TEvent& event ) mouse.x = max( mouse.x, 1 ); int pos = mouse.x + firstPos - 1; pos = max( pos, 0 ); - pos = min( pos, strlen(data) ); - return pos; + TStringView text = data; + pos = min( pos, strwidth(text) ); + return TText::wseek(text, pos); +} + +int TInputLine::displayedPos( int pos ) +{ + return strwidth( TStringView(data, pos) ); } void TInputLine::deleteSelect() @@ -166,6 +172,17 @@ void TInputLine::deleteSelect() } } +void TInputLine::deleteCurrent() +{ + TStringView text = data; + if( curPos < text.size() ) + { + selStart = curPos; + selEnd = curPos + TText::next(text.substr(curPos)); + deleteSelect(); + } +} + void TInputLine::adjustSelectBlock() { if (curPos < anchor) @@ -243,7 +260,7 @@ void TInputLine::handleEvent( TEvent& event ) static char padKeys[] = {0x47,0x4b,0x4d,0x4f,0x73,0x74, 0}; TView::handleEvent(event); - int delta, i; + int delta, i, len, curWidth; if( (state & sfSelected) != 0 ) switch( event.what ) { @@ -296,12 +313,10 @@ void TInputLine::handleEvent( TEvent& event ) switch( event.keyDown.keyCode ) { case kbLeft: - if( curPos > 0 ) - curPos--; + curPos -= TText::prev(TStringView(data), curPos); break; case kbRight: - if( curPos < strlen(data) ) - curPos++; + curPos += TText::next(TStringView(data+curPos)); break; case kbHome: curPos = 0; @@ -312,41 +327,39 @@ void TInputLine::handleEvent( TEvent& event ) case kbBack: if( curPos > 0 ) { - strcpy( data+curPos-1, data+curPos ); - curPos--; + TStringView text = data; + int len = TText::prev(text, curPos); + memmove( data+curPos-len, data+curPos, text.size()-curPos+1 ); + curPos -= len; checkValid(True); } break; case kbDel: if( selStart == selEnd ) - if( curPos < strlen(data) ) - { - selStart = curPos; - selEnd = curPos + 1; - } - deleteSelect(); + deleteCurrent(); + else + deleteSelect(); checkValid(True); break; case kbIns: setState(sfCursorIns, Boolean(!(state & sfCursorIns))); break; default: - if( event.keyDown.charScan.charCode >= ' ' ) + if( (len = event.keyDown.textLength) ) { deleteSelect(); if( (state & sfCursorIns) != 0 ) - /* The following must be a signed comparison! */ - if( curPos < (int) strlen(data) ) - strcpy( data + curPos, data + curPos + 1 ); + deleteCurrent(); if( checkValid(True) ) { - if( strlen(data) < maxLen ) + if( strlen(data) + len <= maxLen ) { if( firstPos > curPos ) firstPos = curPos; - memmove( data+curPos+1, data+curPos, strlen(data+curPos)+1 ); - data[curPos++] = event.keyDown.charScan.charCode; + memmove( data+curPos+len, data+curPos, strlen(data+curPos)+1 ); + memcpy( data+curPos, event.keyDown.text, len ); + curPos += len; } checkValid(False); } @@ -366,9 +379,10 @@ void TInputLine::handleEvent( TEvent& event ) selStart = 0; selEnd = 0; } - if( firstPos > curPos ) - firstPos = curPos; - i = curPos - size.x + 2; + curWidth = displayedPos(curPos); + if( firstPos > curWidth ) + firstPos = curWidth; + i = curWidth - size.x + 2; if( firstPos < i ) firstPos = i; drawView(); @@ -384,7 +398,7 @@ void TInputLine::selectAll( Boolean enable ) curPos = selEnd = strlen(data); else curPos = selEnd = 0; - firstPos = max( 0, curPos-size.x+2 ); + firstPos = max( 0, displayedPos(curPos)-size.x+2 ); drawView(); }