fix: fixed incorrect CURSOR ON impl, and compiler.lua CURSOR codegen. (…

…#436)

Also changed how opl.lua CURSOR() API works, similarly iohandler
textEditor(), so the CURSOR OPL API actually works (rather than just the
opl.lua CURSOR() API).

examples/Tests/cursor.txt

@@ -0,0 +1,17 @@
+DECLARE EXTERNAL
+INCLUDE "const.oph"
+
+PROC main:
+    REM text cursor
+    PRINT "Hello";
+    CURSOR ON
+    GET
+
+    REM graphics cursor
+    gAT 50, 50
+    gFONT KFontArialNormal32&
+    gPRINT "Hello"
+    CURSOR gIDENTITY
+    gUPDATE
+    GET
+ENDP

examples/Tests/dialog.txt

@@ -227,6 +227,15 @@ PROC fileDlg:
 	GET
 ENDP
 
+PROC emptyChoiceDlg:
+	LOCAL ch%
+	dINIT "Empty choice list dialog"
+	dCHOICE ch%, "Choose", ""
+	PRINT DIALOG
+	GET
+ENDP
+
+
 PROC loop%:
 	LOCAL dlg%
 	EXTERNAL choice%
@@ -236,7 +245,7 @@ PROC loop%:
 	dCHOICE choice%, "Choose", "long,float,edit,checkbox,text,..."
 	dCHOICE choice%, "", "password,empty,date,time,..."
 	dCHOICE choice%, "", "buttons,bareButtons,cancelDlg,..."
-	dCHOICE choice%, "", "editmulti,file"
+	dCHOICE choice%, "", "editmulti,file,emptychoice"
 	dBUTTONS "OK", 13, "Cancel", -(512 + %q)
 	choice% = 2
 	dlg% = DIALOG
@@ -274,6 +283,8 @@ PROC loop%:
 		editMultiDlg:
 	ELSEIF choice% = 14
 		fileDlg:
+	ELSEIF choice% = 15
+		emptyChoiceDlg:
 	ENDIF
 
 	RETURN 1

src/compiler.lua

@@ -2271,7 +2271,12 @@ function handleOp_CURSOR(procState)
         for i, arg in ipairs(args) do
             procState:emitExpression(arg, declArgs[i])
         end
-        qualifier = #args - 1
+        -- This command is unusual in how qualifier is used...
+        if #args == 1 then
+            qualifier = 2
+        else
+            qualifier = #args - 1 -- ie 3 or 4
+        end
     end
     procState:emit("BB", opcodes.Cursor, qualifier)
     if args then

src/dialog.lua

@@ -405,9 +405,8 @@ end
 
 function DialogItemEdit:updateCursorIfFocussed()
     if self.hasFocus then
-        gAT(self:getCursorPos())
-        local _, h, ascent = gTWIDTH("", kDialogFont)
-        CURSOR(gIDENTITY(), ascent + 1, self.cursorWidth, h + 1)
+        local x, y = self:getCursorPos()
+        CURSOR(gIDENTITY(), x, y, self.cursorWidth, self.charh + 1)
     end
 end
 
@@ -450,7 +449,7 @@ function DialogItemEdit:setFocus(flag)
         -- When focussed, the draw call triggered by View.setFocus takes care of calling CURSOR (via updateCursorIfFocussed)
         self:updateIohandler()
     else
-        CURSOR(false)
+        CURSOR(nil)
         runtime:iohandler().textEditor(nil)
     end
 end
@@ -467,19 +466,27 @@ function DialogItemEdit:onEditorChanged()
 end
 
 function DialogItemEdit:updateIohandler()
-    local origx, origy = gORIGINX(), gORIGINY()
     local rect = {
-        x = origx + self.x + self.promptWidth,
-        y = origy + self.y,
+        x = self.x + self.promptWidth,
+        y = self.y,
         w = self.w - self.promptWidth,
         h = self.h,
     }
+    local cursorx, cursory = self:getCursorPos()
+    -- The cursor might not actually be showing at this point (eg when DialogItemPartEditor supresses the cursor) but
+    -- this is where it _should_ be.
+    local cursorRect = {
+        x = cursorx,
+        y = cursory,
+        w = self.cursorWidth,
+        h = self.charh + 1, --  This is not quite correct for DialogItemEditMulti but it doesn't really matter
+    }
     runtime:iohandler().textEditor({
         id = gIDENTITY(),
         rect = rect,
         contents = self.editor.value,
         type = self:inputType(),
-        cursorPos = self.editor.cursorPos - 1, -- Zero based for native code
+        cursorRect = cursorRect,
     })
 end
 
@@ -801,7 +808,7 @@ function DialogItemPartEditor:updateCursorIfFocussed()
         if self.editor:hasSelection() then
             -- We don't show a cursor when there's a selection (because a selection is used to indicate the entry is
             -- complete).
-            CURSOR(false)
+            CURSOR(nil)
         else
             DialogItemEdit.updateCursorIfFocussed(self)
         end
@@ -1349,12 +1356,10 @@ function DialogItemEditMulti:updateCursorIfFocussed()
     if self.hasFocus then
         local x, y = self:getCursorPos()
         if x then
-            gAT(x, y)
-            local _, _, ascent = gTWIDTH("", kDialogFont)
-            CURSOR(gIDENTITY(), ascent + 1, self.cursorWidth, self:lineHeight())
+            CURSOR(gIDENTITY(), x, y, self.cursorWidth, self:lineHeight())
         else
             -- Cursor not visible in the currently shown lines
-            CURSOR(false)
+            CURSOR(nil)
         end
     end
 end
@@ -1543,8 +1548,8 @@ function DialogChoiceList:draw()
     black()
 
     if self.typeable and self.hasFocus then
-        gAT(x + self.choiceTextSpace + gTWIDTH(text:sub(1, self.cursorPos - 1)), texty)
-        CURSOR(gIDENTITY(), nil, gTWIDTH(text:sub(self.cursorPos, self.cursorPos)))
+        local cursorx = x + self.choiceTextSpace + gTWIDTH(text:sub(1, self.cursorPos - 1))
+        CURSOR(gIDENTITY(), cursorx, texty, gTWIDTH(text:sub(self.cursorPos, self.cursorPos)))
     end
 
     View.draw(self)

src/opl.lua

@@ -695,46 +695,27 @@ function BUSY(text, corner, delay)
     runtime:restoreGraphicsState(state)
 end
 
-function CURSOR(id, asc, w, h, t)
-    -- printf("CURSOR id=%s, asc=%s, w=%s, h=%s, t=%s\n", id, asc, w, h, t)
+-- Unlike the OPL CURSOR command, the x and y coordinates are explicit and indicate the top left of the cursor.
+-- Therefore, no ascent parameter is necessary.
+function CURSOR(id, x, y, w, h, t)
+    -- printf("CURSOR id=%s, x=%s, y=%s, w=%s, h=%s, t=%s\n", id, x, y, w, h, t)
     runtime:flushGraphicsOps()
     local cursor = runtime:getResource("cursor")
-    if id == false then
+    if id == nil then
         if cursor then
             cursor.shown = false
         end
         runtime:iohandler().graphicsop("cursor", nil)
-    elseif id == true then
-        if cursor == nil then
-            -- What happens if you get a CURSOR ON without any previous config?
-            return
-        end
-        if not cursor.shown then
-            cursor.shown = true
-            runtime:iohandler().graphicsop("cursor", cursor)
-        end
     else
-        local fontw, fonth, fontAscent
-        if not h or not asc then
-            fontw, fonth, fontAscent = runtime:gTWIDTH("0")
-        end
-        if not asc then
-            asc = fontAscent
-        end
-        if not w then
-            w = 2
-        end
-        if not h then
-            h = fonth
-        end
-        if not t then
-            t = 0
-        end
         local win = assert(runtime:getGraphicsContext(id), "Bad id for CURSOR")
         assert(win.isWindow, "Cannot call CURSOR on a bitmap")
 
-        if cursor and cursor.shown and id == cursor.id and asc == cursor.ascent
-            and win.pos.x == cursor.rect.x and win.pos.y == cursor.rect.y
+        if t == nil then
+            t = 0
+        end
+
+        if cursor and cursor.shown and id == cursor.id
+            and x == cursor.rect.x and y == cursor.rect.y
             and w == cursor.rect.w and h == cursor.rect.h and t == cursor.flags then
             -- Cursor has not moved or changed, don't interrupt the timing
             return
@@ -745,14 +726,14 @@ function CURSOR(id, asc, w, h, t)
             runtime:setResource("cursor", cursor)
         end
         cursor.id = id
-        cursor.ascent = asc or fontAscent
+        cursor.shown = true
         cursor.rect = {
-            x = win.pos.x,
-            y = win.pos.y,
-            w = w or 2,
-            h = h or fonth,
+            x = x,
+            y = y,
+            w = w,
+            h = h,
         }
-        cursor.flags = t or 0
+        cursor.flags = t
         runtime:iohandler().graphicsop("cursor", cursor)
     end
 end

src/ops.lua

@@ -1471,21 +1471,37 @@ function Create_dump(runtime)
 end
 
 function Cursor(stack, runtime) -- 0xA6
-    local numParams = runtime:IP8()
-    if numParams == 0 then
-        runtime:CURSOR(false)
-    elseif numParams == 1 then
-        runtime:CURSOR(true)
+    local immediate = runtime:IP8()
+    if immediate == 0 then
+        -- CURSOR OFF
+        runtime:CURSOR(nil)
+    elseif immediate == 1 then
+        -- CURSOR ON means text cursor, in the default window
+        local screen = runtime:getGraphics().screen
+        local x = screen.x + (screen.cursorx * screen.charw)
+        local y = screen.y + (screen.cursory * screen.charh)
+        runtime:CURSOR(KDefaultWin, x, y, screen.charw, screen.charh)
     else
+        -- CURSOR <window> [, ascent, width, height [, type]
         local t = nil
-        if numParams == 4 then
+        if immediate == 4 then
             t = stack:pop()
-        else
-            assert(numParams == 3, "Bad immediate after Cursor!")
         end
-        -- numParams doesn't include id...
-        local id, asc, w, h = stack:pop(4)
-        runtime:CURSOR(id, asc, w, h, t)
+        local asc, w, h
+        if immediate >= 3 then
+            asc, w, h = stack:pop(3)
+        end
+        local id = stack:pop()
+
+        if asc == nil then
+            local _
+            _, h, asc = runtime:gTWIDTH("")
+            w = 2
+        end
+        local context = runtime:getGraphicsContext(id)
+        local x = context.pos.x
+        local y = context.pos.y - asc
+        runtime:CURSOR(id, x, y, w, h, t)
     end
 end
 

swift/OpoIoHandler.swift

@@ -326,7 +326,6 @@ public struct Graphics {
     public struct Cursor: Codable {
         let id: DrawableId
         let rect: Rect
-        let ascent: Int
         let flags: FlagSet<CursorFlag>
     }
 
@@ -544,9 +543,9 @@ public struct TextFieldInfo: Codable {
     }
     let id: Graphics.DrawableId
     let type: InputType
-    let rect: Graphics.Rect
+    let rect: Graphics.Rect? // bounding rect of the whole text field, in id's coords, if available
     let contents: String
-    let cursorPos: Int
+    let cursorRect: Graphics.Rect // location of cursor, in coords of id
 }
 
 public protocol FileSystemIoHandler {