tdf#152460: Improve script handling in style previews

Use Edit Engine to get the script types instead of trying to duplicate
(poorly) its behaviour. This has the advantage of handling weak
characters and digits properly and is closer to what would happen in the
document itself.

We probably should go further and render the preview entirely using Edit
Engine (since the current code fails short of proper bidi handling), but
this is a bigger change.

Change-Id: I79b28067d80f66087e1d5e9399ba1a513de96c8a
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/144283
Tested-by: Jenkins
Reviewed-by: خالد حسني <khaled@aliftype.com>

1 files changed, 21 insertions, 37 deletions

diff --git a/svx/source/styles/CommonStylePreviewRenderer.cxx b/svx/source/styles/CommonStylePreviewRenderer.cxx
index 5f12d209f0bf..9ddf3cf15017 100644
--- a/svx/source/styles/CommonStylePreviewRenderer.cxx
+++ b/svx/source/styles/CommonStylePreviewRenderer.cxx
@@ -29,6 +29,7 @@
 #include <editeng/contouritem.hxx>
 #include <editeng/colritem.hxx>
 #include <editeng/crossedoutitem.hxx>
+#include <editeng/editeng.hxx>
 #include <editeng/emphasismarkitem.hxx>
 #include <editeng/postitem.hxx>
 #include <editeng/shdditem.hxx>
@@ -39,9 +40,6 @@
 
 #include <editeng/editids.hrc>
 
-#include <comphelper/processfactory.hxx>
-#include <com/sun/star/i18n/ScriptType.hpp>
-
 using namespace css;
 
 namespace svx
@@ -235,7 +233,7 @@ void CommonStylePreviewRenderer::CalcRenderSize()
 
     mnBaseLine = 0;
     mnHeight = 0;
-    sal_uInt16 nScript;
+    SvtScriptType aScript;
     sal_uInt16 nIdx = 0;
     sal_Int32 nStart = 0;
     sal_Int32 nEnd;
@@ -244,19 +242,19 @@ void CommonStylePreviewRenderer::CalcRenderSize()
     if (nCnt)
     {
         nEnd = maScriptChanges[nIdx].changePos;
-        nScript = maScriptChanges[nIdx].scriptType;
+        aScript = maScriptChanges[nIdx].scriptType;
     }
     else
     {
         nEnd = rText.getLength();
-        nScript = css::i18n::ScriptType::LATIN;
+        aScript = SvtScriptType::LATIN;
     }
 
     do
     {
-        auto oFont = (nScript == css::i18n::ScriptType::ASIAN) ?
+        auto oFont = (aScript == SvtScriptType::ASIAN) ?
                          m_oCJKFont :
-                         ((nScript == css::i18n::ScriptType::COMPLEX) ?
+                         ((aScript == SvtScriptType::COMPLEX) ?
                              m_oCTLFont :
                              m_oFont);
 
@@ -287,7 +285,7 @@ void CommonStylePreviewRenderer::CalcRenderSize()
         {
             nStart = nEnd;
             nEnd = maScriptChanges[nIdx].changePos;
-            nScript = maScriptChanges[nIdx].scriptType;
+            aScript = maScriptChanges[nIdx].scriptType;
         }
         else
             break;
@@ -351,7 +349,7 @@ bool CommonStylePreviewRenderer::render(const tools::Rectangle& aRectangle, Rend
             aFontDrawPosition.AdjustY((aRectangle.GetHeight() - mnHeight) / 2 );
     }
 
-    sal_uInt16 nScript;
+    SvtScriptType aScript;
     sal_uInt16 nIdx = 0;
     sal_Int32 nStart = 0;
     sal_Int32 nEnd;
@@ -359,19 +357,19 @@ bool CommonStylePreviewRenderer::render(const tools::Rectangle& aRectangle, Rend
     if (nCnt)
     {
         nEnd = maScriptChanges[nIdx].changePos;
-        nScript = maScriptChanges[nIdx].scriptType;
+        aScript = maScriptChanges[nIdx].scriptType;
     }
     else
     {
         nEnd = rText.getLength();
-        nScript = css::i18n::ScriptType::LATIN;
+        aScript = SvtScriptType::LATIN;
     }
 
     do
     {
-        auto oFont = (nScript == css::i18n::ScriptType::ASIAN)
+        auto oFont = (aScript == SvtScriptType::ASIAN)
                          ? m_oCJKFont
-                         : ((nScript == css::i18n::ScriptType::COMPLEX)
+                         : ((aScript == SvtScriptType::COMPLEX)
                              ? m_oCTLFont
                              : m_oFont);
 
@@ -392,7 +390,7 @@ bool CommonStylePreviewRenderer::render(const tools::Rectangle& aRectangle, Rend
         {
             nStart = nEnd;
             nEnd = maScriptChanges[nIdx].changePos;
-            nScript = maScriptChanges[nIdx].scriptType;
+            aScript = maScriptChanges[nIdx].scriptType;
         }
         else
             break;
@@ -413,30 +411,16 @@ void CommonStylePreviewRenderer::CheckScript()
     maScriptText = maStyleName;
     maScriptChanges.clear();
 
-    if (!mxBreak.is())
-    {
-        auto xContext = comphelper::getProcessComponentContext();
-        mxBreak = css::i18n::BreakIterator::create(xContext);
-    }
-
-    sal_Int16 nScript = mxBreak->getScriptType(maStyleName, 0);
-    sal_Int32 nChg = 0;
-    if (css::i18n::ScriptType::WEAK == nScript)
-    {
-        nChg = mxBreak->endOfScript(maStyleName, nChg, nScript);
-        if (nChg < maStyleName.getLength())
-            nScript = mxBreak->getScriptType(maStyleName, nChg);
-        else
-            nScript = css::i18n::ScriptType::LATIN;
-    }
+    auto aEditEngine = EditEngine(nullptr);
+    aEditEngine.SetText(maScriptText);
 
-    while (true)
+    auto aScript = aEditEngine.GetScriptType({ 0, 0, 0, 0 });
+    for (sal_Int32 i = 1; i <= maScriptText.getLength(); i++)
     {
-        nChg = mxBreak->endOfScript(maStyleName, nChg, nScript);
-        maScriptChanges.emplace_back(nScript, nChg);
-        if (nChg >= maStyleName.getLength() || nChg < 0)
-            break;
-        nScript = mxBreak->getScriptType(maStyleName, nChg);
+        auto aNextScript = aEditEngine.GetScriptType({ 0, i, 0, i });
+        if (aNextScript != aScript || i == maScriptText.getLength())
+            maScriptChanges.emplace_back(aScript, i);
+        aScript = aNextScript;
     }
 }