Simplify text width settings (#943)

* Remove the fixed text width switch, resolves #924
* Update tests
* Clean up code to set text width and add to viewer

novelwriter/gui/doceditor.py

@@ -509,8 +509,8 @@ class GuiDocEditor(QTextEdit):
 
     def updateDocMargins(self):
         """Automatically adjust the margins so the text is centred if
-        Config.textFixedW is enabled or we're in Focus Mode. Otherwise,
-        just ensure the margins are set correctly.
+        we have a text width set or we're in Focus Mode. Otherwise, just
+        ensure the margins are set correctly.
         """
         wW = self.width()
         wH = self.height()
@@ -522,16 +522,10 @@ class GuiDocEditor(QTextEdit):
         hBar = self.horizontalScrollBar()
         sH = hBar.height() if hBar.isVisible() else 0
 
-        if self.mainConf.textFixedW or self.theParent.isFocusMode:
-            if self.theParent.isFocusMode:
-                tW = self.mainConf.getFocusWidth()
-            else:
-                tW = self.mainConf.getTextWidth()
-            tM = (wW - sW - tW)//2
-            if tM < cM:
-                tM = cM
-        else:
-            tM = cM
+        tM = cM
+        if self.mainConf.textWidth > 0 or self.theParent.isFocusMode:
+            tW = self.mainConf.getTextWidth(self.theParent.isFocusMode)
+            tM = max((wW - sW - tW)//2, cM)
 
         tB = self.frameWidth()
         tW = wW - 2*tB - sW
@@ -541,13 +535,12 @@ class GuiDocEditor(QTextEdit):
         self.docHeader.setGeometry(tB, tB, tW, tH)
         self.docFooter.setGeometry(tB, fY, tW, fH)
 
+        rH = 0
         if self.docSearch.isVisible():
             rH = self.docSearch.height()
             rW = self.docSearch.width()
             rL = wW - sW - rW - 2*tB
             self.docSearch.move(rL, 2*tB)
-        else:
-            rH = 0
 
         uM = max(cM, tH, rH)
         lM = max(cM, fH)