From de993bc0cdb7202390c9ed1d0c4e0a5b33d1d0ee Mon Sep 17 00:00:00 2001
From: "Kartik K. Agaram" <vc@akkartik.com>
Date: Thu, 15 Apr 2021 22:00:03 -0700
Subject: [PATCH] shell: primitives for screen size

---
 shell/global.mu | 182 +++++++++++++++++++++++++++++++++++++++++++++++-
 1 file changed, 180 insertions(+), 2 deletions(-)

diff --git a/shell/global.mu b/shell/global.mu
index 94c334e1..693def1b 100644
--- a/shell/global.mu
+++ b/shell/global.mu
@@ -30,12 +30,16 @@ fn initialize-globals _self: (addr global-table) {
   append-primitive self, "cons"
   # for screens
   append-primitive self, "print"
-  append-primitive self, "pixel"
+  append-primitive self, "lines"
+  append-primitive self, "columns"
   append-primitive self, "up"
   append-primitive self, "down"
   append-primitive self, "left"
   append-primitive self, "right"
   append-primitive self, "cr"
+  append-primitive self, "pixel"
+  append-primitive self, "width"
+  append-primitive self, "height"
   # for keyboards
   append-primitive self, "key"
   # for streams
@@ -152,7 +156,7 @@ fn render-globals screen: (addr screen), _self: (addr global-table), xmin: int,
 
 fn render-primitives screen: (addr screen), xmin: int, ymin: int, xmax: int, ymax: int {
   var y/ecx: int <- copy ymax
-  y <- subtract 0xc
+  y <- subtract 0xe
   var tmpx/eax: int <- copy xmin
   tmpx <- draw-text-rightward screen, "cursor graphics", tmpx, xmax, y, 0x7/fg=grey, 0x12/bg=almost-black
   y <- increment
@@ -161,6 +165,10 @@ fn render-primitives screen: (addr screen), xmin: int, ymin: int, xmax: int, yma
   tmpx <- draw-text-rightward screen, ": screen a -> a", tmpx, xmax, y, 0x7/fg=grey, 0x12/bg=almost-black
   y <- increment
   var tmpx/eax: int <- copy xmin
+  tmpx <- draw-text-rightward screen, "  lines columns", tmpx, xmax, y, 0x2a/fg=orange, 0x12/bg=almost-black
+  tmpx <- draw-text-rightward screen, ": screen -> number", tmpx, xmax, y, 0x7/fg=grey, 0x12/bg=almost-black
+  y <- increment
+  var tmpx/eax: int <- copy xmin
   tmpx <- draw-text-rightward screen, "  up down left right", tmpx, xmax, y, 0x2a/fg=orange, 0x12/bg=almost-black
   tmpx <- draw-text-rightward screen, ": screen", tmpx, xmax, y, 0x7/fg=grey, 0x12/bg=almost-black
   y <- increment
@@ -172,6 +180,10 @@ fn render-primitives screen: (addr screen), xmin: int, ymin: int, xmax: int, yma
   tmpx <- draw-text-rightward screen, "pixel graphics", tmpx, xmax, y, 0x7/fg=grey, 0x12/bg=almost-black
   y <- increment
   var tmpx/eax: int <- copy xmin
+  tmpx <- draw-text-rightward screen, "  width height", tmpx, xmax, y, 0x2a/fg=orange, 0x12/bg=almost-black
+  tmpx <- draw-text-rightward screen, ": screen -> number", tmpx, xmax, y, 0x7/fg=grey, 0x12/bg=almost-black
+  y <- increment
+  var tmpx/eax: int <- copy xmin
   tmpx <- draw-text-rightward screen, "  pixel", tmpx, xmax, y, 0x2a/fg=orange, 0x12/bg=almost-black
   tmpx <- draw-text-rightward screen, ": screen x y color", tmpx, xmax, y, 0x7/fg=grey, 0x12/bg=almost-black
   y <- increment
@@ -455,6 +467,20 @@ fn apply-primitive _f: (addr cell), args-ah: (addr handle cell), out: (addr hand
     apply-print args-ah, out, trace
     return
   }
+  {
+    var is-lines?/eax: boolean <- string-equal? f-name, "lines"
+    compare is-lines?, 0/false
+    break-if-=
+    apply-lines args-ah, out, trace
+    return
+  }
+  {
+    var is-columns?/eax: boolean <- string-equal? f-name, "columns"
+    compare is-columns?, 0/false
+    break-if-=
+    apply-columns args-ah, out, trace
+    return
+  }
   {
     var is-up?/eax: boolean <- string-equal? f-name, "up"
     compare is-up?, 0/false
@@ -497,6 +523,20 @@ fn apply-primitive _f: (addr cell), args-ah: (addr handle cell), out: (addr hand
     apply-pixel args-ah, out, trace
     return
   }
+  {
+    var is-width?/eax: boolean <- string-equal? f-name, "width"
+    compare is-width?, 0/false
+    break-if-=
+    apply-width args-ah, out, trace
+    return
+  }
+  {
+    var is-height?/eax: boolean <- string-equal? f-name, "height"
+    compare is-height?, 0/false
+    break-if-=
+    apply-height args-ah, out, trace
+    return
+  }
   {
     var wait-for-key?/eax: boolean <- string-equal? f-name, "key"
     compare wait-for-key?, 0/false
@@ -1407,3 +1447,141 @@ fn apply-write _args-ah: (addr handle cell), out: (addr handle cell), trace: (ad
   # return the stream
   copy-object first-ah, out
 }
+
+fn apply-lines _args-ah: (addr handle cell), out: (addr handle cell), trace: (addr trace) {
+  trace-text trace, "eval", "apply lines"
+  var args-ah/eax: (addr handle cell) <- copy _args-ah
+  var _args/eax: (addr cell) <- lookup *args-ah
+  var args/esi: (addr cell) <- copy _args
+  # TODO: check that args is a pair
+  var empty-args?/eax: boolean <- nil? args
+  compare empty-args?, 0/false
+  {
+    break-if-=
+    error trace, "lines needs 1 arg but got 0"
+    return
+  }
+  # screen = args->left
+  var first-ah/eax: (addr handle cell) <- get args, left
+  var first/eax: (addr cell) <- lookup *first-ah
+  var first-type/ecx: (addr int) <- get first, type
+  compare *first-type, 5/screen
+  {
+    break-if-=
+    error trace, "first arg for 'lines' is not a screen"
+    return
+  }
+  var screen-ah/eax: (addr handle screen) <- get first, screen-data
+  var _screen/eax: (addr screen) <- lookup *screen-ah
+  var screen/edx: (addr screen) <- copy _screen
+  # compute dimensions
+  var dummy/eax: int <- copy 0
+  var height/ecx: int <- copy 0
+  dummy, height <- screen-size screen
+  var result/xmm0: float <- convert height
+  new-float out, result
+}
+
+fn apply-columns _args-ah: (addr handle cell), out: (addr handle cell), trace: (addr trace) {
+  trace-text trace, "eval", "apply columns"
+  var args-ah/eax: (addr handle cell) <- copy _args-ah
+  var _args/eax: (addr cell) <- lookup *args-ah
+  var args/esi: (addr cell) <- copy _args
+  # TODO: check that args is a pair
+  var empty-args?/eax: boolean <- nil? args
+  compare empty-args?, 0/false
+  {
+    break-if-=
+    error trace, "columns needs 1 arg but got 0"
+    return
+  }
+  # screen = args->left
+  var first-ah/eax: (addr handle cell) <- get args, left
+  var first/eax: (addr cell) <- lookup *first-ah
+  var first-type/ecx: (addr int) <- get first, type
+  compare *first-type, 5/screen
+  {
+    break-if-=
+    error trace, "first arg for 'columns' is not a screen"
+    return
+  }
+  var screen-ah/eax: (addr handle screen) <- get first, screen-data
+  var _screen/eax: (addr screen) <- lookup *screen-ah
+  var screen/edx: (addr screen) <- copy _screen
+  # compute dimensions
+  var width/eax: int <- copy 0
+  var dummy/ecx: int <- copy 0
+  width, dummy <- screen-size screen
+  var result/xmm0: float <- convert width
+  new-float out, result
+}
+
+fn apply-width _args-ah: (addr handle cell), out: (addr handle cell), trace: (addr trace) {
+  trace-text trace, "eval", "apply width"
+  var args-ah/eax: (addr handle cell) <- copy _args-ah
+  var _args/eax: (addr cell) <- lookup *args-ah
+  var args/esi: (addr cell) <- copy _args
+  # TODO: check that args is a pair
+  var empty-args?/eax: boolean <- nil? args
+  compare empty-args?, 0/false
+  {
+    break-if-=
+    error trace, "width needs 1 arg but got 0"
+    return
+  }
+  # screen = args->left
+  var first-ah/eax: (addr handle cell) <- get args, left
+  var first/eax: (addr cell) <- lookup *first-ah
+  var first-type/ecx: (addr int) <- get first, type
+  compare *first-type, 5/screen
+  {
+    break-if-=
+    error trace, "first arg for 'width' is not a screen"
+    return
+  }
+  var screen-ah/eax: (addr handle screen) <- get first, screen-data
+  var _screen/eax: (addr screen) <- lookup *screen-ah
+  var screen/edx: (addr screen) <- copy _screen
+  # compute dimensions
+  var width/eax: int <- copy 0
+  var dummy/ecx: int <- copy 0
+  width, dummy <- screen-size screen
+  width <- shift-left 3/log2-font-width
+  var result/xmm0: float <- convert width
+  new-float out, result
+}
+
+fn apply-height _args-ah: (addr handle cell), out: (addr handle cell), trace: (addr trace) {
+  trace-text trace, "eval", "apply height"
+  var args-ah/eax: (addr handle cell) <- copy _args-ah
+  var _args/eax: (addr cell) <- lookup *args-ah
+  var args/esi: (addr cell) <- copy _args
+  # TODO: check that args is a pair
+  var empty-args?/eax: boolean <- nil? args
+  compare empty-args?, 0/false
+  {
+    break-if-=
+    error trace, "height needs 1 arg but got 0"
+    return
+  }
+  # screen = args->left
+  var first-ah/eax: (addr handle cell) <- get args, left
+  var first/eax: (addr cell) <- lookup *first-ah
+  var first-type/ecx: (addr int) <- get first, type
+  compare *first-type, 5/screen
+  {
+    break-if-=
+    error trace, "first arg for 'height' is not a screen"
+    return
+  }
+  var screen-ah/eax: (addr handle screen) <- get first, screen-data
+  var _screen/eax: (addr screen) <- lookup *screen-ah
+  var screen/edx: (addr screen) <- copy _screen
+  # compute dimensions
+  var dummy/eax: int <- copy 0
+  var height/ecx: int <- copy 0
+  dummy, height <- screen-size screen
+  height <- shift-left 4/log2-font-height
+  var result/xmm0: float <- convert height
+  new-float out, result
+}