add searchScrollColumn to NORMAL_SEARCH_MODE variant, and update and recalculate it where needed

fcore/app-type.sml

@@ -2,8 +2,12 @@ structure AppType =
 struct
   datatype mode =
     NORMAL_MODE of string
-  | NORMAL_SEARCH_MODE of {searchString: string, tempSearchList: int vector,
+  | NORMAL_SEARCH_MODE of
-  searchCursorIdx: int}
+      { searchString: string
+      , tempSearchList: int vector
+      , searchCursorIdx: int
+      , searchScrollColumn: int
+      }
 
   type app_type =
     { mode: mode

fcore/normal-mode/normal-mode.sml

@@ -7,7 +7,7 @@ struct
 
   fun switchToNormalSearchMode (app: app_type) =
     NormalSearchFinish.onSearchChanged
-      (app, "", Vector.fromList [], 0, #buffer app)
+      (app, "", Vector.fromList [], 0, 0, #buffer app)
 
   fun getNumLength (pos, str) =
     if pos = String.size str then

fcore/normal-mode/normal-search-finish.sml

@@ -4,7 +4,13 @@ struct
   open DrawMsg
 
   fun onSearchChanged
-    (app: app_type, searchString, tempSearchList, searchCursorIdx, buffer) =
+    ( app: app_type
+    , searchString
+    , tempSearchList
+    , searchCursorIdx
+    , searchScrollColumn
+    , buffer
+    ) =
     let
       val
         { buffer
@@ -16,10 +22,15 @@ struct
         , ...
         } = app
 
+      val searchScrollColumn =
+        TextScroll.getScrollColumnFromString
+          (searchCursorIdx, windowWidth, searchScrollColumn)
+
       val mode = NORMAL_SEARCH_MODE
         { searchString = searchString
         , tempSearchList = tempSearchList
         , searchCursorIdx = searchCursorIdx
+        , searchScrollColumn = searchScrollColumn
         }
 
       val floatWindowWidth = Real32.fromInt windowWidth

fcore/normal-mode/normal-search-mode.sml

@@ -9,7 +9,8 @@ struct
     in SearchList.buildRange (buffer, unescapedString, cursorIdx + 1111)
     end
 
-  fun addChr (app: app_type, searchString, searchCursorIdx, chr) =
+  fun addChr
+    (app: app_type, searchString, searchCursorIdx, searchScrollColumn, chr) =
     let
       val {cursorIdx, buffer, ...} = app
 
@@ -31,7 +32,13 @@ struct
       val tempSearchList = buildTempSearchList (searchString, buffer, cursorIdx)
     in
       NormalSearchFinish.onSearchChanged
-        (app, searchString, tempSearchList, searchCursorIdx, buffer)
+        ( app
+        , searchString
+        , tempSearchList
+        , searchCursorIdx
+        , searchScrollColumn
+        , buffer
+        )
     end
 
   (* return to normal mode, keeping the same searchString and searchList
@@ -87,7 +94,13 @@ struct
         (app, buffer, searchString, tempSearchList, startLine, mode, msgs)
     end
 
-  fun backspace (app: app_type, searchString, tempSearchList, searchCursorIdx) =
+  fun backspace
+    ( app: app_type
+    , searchString
+    , tempSearchList
+    , searchScrollColumn
+    , searchCursorIdx
+    ) =
     if searchCursorIdx = 0 then
       app
     else
@@ -112,10 +125,17 @@ struct
           buildTempSearchList (searchString, buffer, cursorIdx)
       in
         NormalSearchFinish.onSearchChanged
-          (app, searchString, tempSearchList, searchCursorIdx, buffer)
+          ( app
+          , searchString
+          , tempSearchList
+          , searchCursorIdx
+          , searchScrollColumn
+          , buffer
+          )
       end
 
-  fun moveLeft (app, searchString, tempSearchList, searchCursorIdx) =
+  fun moveLeft
+    (app, searchString, tempSearchList, searchCursorIdx, searchScrollColumn) =
     if searchCursorIdx = 0 then
       app
     else
@@ -123,10 +143,17 @@ struct
         val searchCursorIdx = searchCursorIdx - 1
       in
         NormalSearchFinish.onSearchChanged
-          (app, searchString, tempSearchList, searchCursorIdx, #buffer app)
+          ( app
+          , searchString
+          , tempSearchList
+          , searchCursorIdx
+          , searchScrollColumn
+          , #buffer app
+          )
       end
 
-  fun moveRight (app, searchString, tempSearchList, searchCursorIdx) =
+  fun moveRight
+    (app, searchString, tempSearchList, searchCursorIdx, searchScrollColumn) =
     if searchCursorIdx = String.size searchString then
       app
     else
@@ -134,20 +161,50 @@ struct
         val searchCursorIdx = searchCursorIdx + 1
       in
         NormalSearchFinish.onSearchChanged
-          (app, searchString, tempSearchList, searchCursorIdx, #buffer app)
+          ( app
+          , searchString
+          , tempSearchList
+          , searchCursorIdx
+          , searchScrollColumn
+          , #buffer app
+          )
       end
 
-  fun update (app, {searchString, tempSearchList, searchCursorIdx}, msg, time) =
+  fun update
+    ( app
+    , {searchString, tempSearchList, searchCursorIdx, searchScrollColumn}
+    , msg
+    , time
+    ) =
     case msg of
-      CHAR_EVENT chr => addChr (app, searchString, searchCursorIdx, chr)
+      CHAR_EVENT chr =>
+        addChr (app, searchString, searchCursorIdx, searchScrollColumn, chr)
     | KEY_BACKSPACE =>
-        backspace (app, searchString, tempSearchList, searchCursorIdx)
+        backspace
+          ( app
+          , searchString
+          , tempSearchList
+          , searchScrollColumn
+          , searchCursorIdx
+          )
     | KEY_ESC => exitToNormalMode app
     | KEY_ENTER => saveSearch (app, searchString, tempSearchList, time)
     | ARROW_LEFT =>
-        moveLeft (app, searchString, tempSearchList, searchCursorIdx)
+        moveLeft
+          ( app
+          , searchString
+          , tempSearchList
+          , searchCursorIdx
+          , searchScrollColumn
+          )
     | ARROW_RIGHT =>
-        moveRight (app, searchString, tempSearchList, searchCursorIdx)
+        moveRight
+          ( app
+          , searchString
+          , tempSearchList
+          , searchCursorIdx
+          , searchScrollColumn
+          )
     | WITH_SEARCH_LIST (searchList, time) =>
         NormalFinish.withSearchList (app, searchList, time)
     | RESIZE_EVENT (width, height) =>

fcore/text-scroll.sml

@@ -34,6 +34,9 @@ struct
         (startOfLine, cursorIdx, windowWidth, prevScrollColumn)
     end
 
+  fun getScrollColumnFromString (cursorIdx, windowWidth, prevScrollColumn) =
+    calculateScrollColumn (0, cursorIdx, windowWidth, prevScrollColumn)
+
   fun getStartLine (prevLineNumber, cursorLine, windowHeight) =
     if cursorLine <= (prevLineNumber + 3) then
       (* cursorLine is prior to or same as prevLineNumber,