work on resizing

editor.nim

@@ -17,20 +17,40 @@ type
     termBuffer: Buffer
     history: seq[TextBuffer] # past texts
     historyIndex: int # where are we in history
+    scroll: Scroll
+    active: bool
+
+    # screen properties passed to renderer
+    width, height: int
+    cursorY: int
 
   EditorResult* = enum
-    erEnter, erCtrlC, erCtrlD, erError
+    erError, erEnter, erCtrlC, erCtrlD
 
 # for editors
 var editors: seq[EditorState]
 
+proc redraw*(ed: EditorState): int =
+  render(ed.textBuffer, ed.termBuffer, ed.prompt, ed.scroll, ed.width, ed.height, ed.cursorY)
+
 # resize support
 onSignal(28):
-  discard
+  let nh = termGetHeight()
+  let nw = termGetWidth()
+  for ed in editors:
+    ed.width = nw
+    ed.height = nh
+    if ed.active:
+      discard ed.redraw()
 
 proc newEditor*(prompt: string = "> "): EditorState =
   new(result)
+  let (_, cursorY) = termGetCursorPos(stdout)
+  result.cursorY = cursorY
+  result.width = termGetWidth()
+  result.height = termGetHeight()
   result.prompt = prompt
+  result.active = false
   editors.add(result)
 
 proc destroyEditor*(oldEditor: EditorState) =
@@ -43,23 +63,23 @@ proc destroyEditor*(oldEditor: EditorState) =
 proc read*(ed: EditorState): (EditorResult, string) =
 
   var editorResult = erError
-  let (_, cursorY) = termGetCursorPos(stdout)
-  ed.termBuffer = newBuffer(0, cursorY, termGetWidth(), 1, stdout)
+  ed.termBuffer = newBuffer(0, ed.cursorY, termGetWidth(), 1, stdout)
   ed.textBuffer = newTextBuffer()
   ed.history.add(ed.textBuffer)
   ed.historyIndex = ed.history.high()
-
-  var scroll: Scroll = new(Scroll)
+  ed.scroll = new(Scroll)
+  ed.active = true
+  var lastRenderLines = 0
 
   template moveInHistory(delta: int) =
     let newHistoryIndex = min(max(ed.historyIndex + delta, 0), ed.history.high())
     if newHistoryIndex != ed.historyIndex:
       ed.textBuffer = ed.history[newHistoryIndex]
-      scroll.reset()
+      ed.scroll.reset()
       ed.historyIndex = newHistoryIndex
 
   while true:
-    render(ed.textBuffer, ed.termBuffer, ed.prompt, scroll)
+    lastRenderLines = ed.redraw()
     let (getKeyResult, key) = getKey()
     case getKeyResult:
     of gkChar:
@@ -114,14 +134,23 @@ proc read*(ed: EditorState): (EditorResult, string) =
         else:
           discard # not implemented
 
+  # stop redraws on resize
+  ed.active = false
+
   # return val, strip final newline (due to how double enter is how you enter)
   let cont = ed.textBuffer.getContent()
+  if editorResult == erError:
+    raise newException(Defect, "Editor loop quit without setting editor result.")
   result = (editorResult, cont)
 
   # cleanup
   stdout.write("\n")
+  ed.cursorY = min(ed.height-1, ed.cursorY + lastRenderLines)
 
   # don't add empty lines to history
   if ed.history[ed.history.high()].getContent() == "":
     ed.history.del(ed.history.high())
-  
+  
+proc updateCursorPos*(ed: EditorState) =
+  let (_, cursorY) = termGetCursorPos(stdout)
+  ed.cursorY = cursorY

example.nim

@@ -10,6 +10,10 @@ while true:
   elif text == "clear":
     eraseScreen()
     setCursorPos(0, 0)
+    e.updateCursorPos()
     continue
   if text.len() > 0:
-    echo text
+    echo text
+    e.updateCursorPos()
+
+e.destroyEditor()

renderer.nim

@@ -15,16 +15,19 @@ proc reset*(scroll: Scroll) =
   scroll.x = 0
   scroll.y = 0
 
-proc render*(textBuffer: TextBuffer, termBuffer: Buffer, prompt: string, scroll: Scroll) =
+proc render*(textBuffer: TextBuffer, termBuffer: Buffer, prompt: string, scroll: Scroll, width, height: int, edCursorY: int): int =
   # we are free to "redraw" everything everytime
   # since termBuffer double buffers
+  # returns how many lines were drawn
 
   # GET INFO
   let (x, y) = textBuffer.getCursorPos()
   let lines = textBuffer.lines()
   let lineCount = lines.len()
-  let termWidth = termGetWidth()
-  let termHeight = termGetHeight()
+  #let termWidth = termGetWidth()
+  let termWidth = width
+  #let termHeight = termGetHeight()
+  let termHeight = height
   let promptLen = prompt.len()
   let maxTextLen = termWidth - promptLen
 
@@ -101,3 +104,5 @@ proc render*(textBuffer: TextBuffer, termBuffer: Buffer, prompt: string, scroll:
   termBuffer.setCursorPos(x + promptLen - scroll.x, y - scroll.y)
   termBuffer.redraw()
 
+  return termBuffer.getHeight()
+

terminalUtils/buffer.nim

@@ -158,6 +158,9 @@ proc redraw*(buf: Buffer, force: bool = false) =
 func getSize*(buf: Buffer): (int, int) =
   (buf.width, buf.height)
 
+func getHeight*(buf: Buffer): int =
+  buf.height
+
 proc resize*(buf: Buffer, newWidth, newHeight: int, terminalWidth, terminalHeight: int) =
 
   # assert sizes

todo.txt

@@ -0,0 +1,11 @@
+Short term goals:
+- fixing TODOs in code
+- finding a better way to do getCursorPos
+- fix resizing
+- fix erasing in buffer
+
+Long term goals:
+- tab autocomplete
+- syntax highlighting
+- more fancy looks
+- windows support