lineedit: rewrite

The old lineedit system worked quite well in the original synchronous
model. However, because it needs access to the terminal, it has been
subtly broken ever since buffer updates are allowed while the user
is in line edit mode.

This is best observed in incremental search, where searching for a
bgcolor'ed text would result in the bgcolor bleeding into the line
editor box.

The new version is much simpler, and therefore less optimized. But
it can still take advantage of output optimization in the terminal
controller, and it is free of races (because we simply query the
current state from the pager and feed it into the main output grid).

1 files changed, 7 insertions, 13 deletions

diff --git a/src/local/pager.nim b/src/local/pager.nim
index 87ac422a..6c18c91c 100644
--- a/src/local/pager.nim
+++ b/src/local/pager.nim
@@ -159,8 +159,11 @@ proc getLineHist(pager: Pager, mode: LineMode): LineHistory =
     pager.linehist[mode] = newLineHistory()
   return pager.linehist[mode]
 
-proc setLineEdit(pager: Pager, prompt: string, mode: LineMode, current = "", hide = false) =
-  pager.lineedit = some(readLine(prompt, pager.attrs.width, current = current, term = pager.term, hide = hide, hist = pager.getLineHist(mode)))
+proc setLineEdit(pager: Pager, prompt: string, mode: LineMode,
+    current = "", hide = false) =
+  let hist = pager.getLineHist(mode)
+  let edit = readLine(prompt, pager.attrs.width, current, {}, hide, hist)
+  pager.lineedit = some(edit)
   pager.linemode = mode
 
 proc clearLineEdit(pager: Pager) =
@@ -344,10 +347,8 @@ proc draw*(pager: Pager) =
   if pager.askpromise != nil:
     discard
   elif pager.lineedit.isSome:
-    if pager.lineedit.get.isnew:
-      #TODO hack
-      # make term notice that it must redraw when status is restored
-      let x = newFixedGrid(pager.attrs.width)
+    if pager.lineedit.get.invalid:
+      let x = pager.lineedit.get.generateOutput()
       pager.term.writeGrid(x, 0, pager.attrs.height - 1)
   else:
     pager.term.writeGrid(pager.statusgrid, 0, pager.attrs.height - 1)
@@ -355,13 +356,6 @@ proc draw*(pager: Pager) =
   if pager.askpromise != nil:
     pager.term.setCursor(pager.askcursor, pager.attrs.height - 1)
   elif pager.lineedit.isSome:
-    if pager.lineedit.get.isnew:
-      #TODO hack
-      pager.term.setCursor(0, pager.attrs.height - 1)
-      pager.lineedit.get.drawPrompt()
-      pager.term.setCursor(pager.lineedit.get.getCursorX(), pager.attrs.height - 1)
-      pager.lineedit.get.fullRedraw()
-      pager.lineedit.get.isnew = false
     pager.term.setCursor(pager.lineedit.get.getCursorX(), pager.attrs.height - 1)
   elif container.select.open:
     pager.term.setCursor(container.select.getCursorX(),