1 files changed, 99 insertions, 0 deletions
diff --git a/prototypes/browse/7.mu b/prototypes/browse/7.mu
new file mode 100644
index 00000000..b319d4a2
--- /dev/null
+++ b/prototypes/browse/7.mu
@@ -0,0 +1,99 @@
+fn main args: (addr array (addr array byte)) -> exit-status/ebx: int {
+  var filename/eax: (addr array byte) <- first-arg args
+  var file/esi: (addr buffered-file) <- load-file filename
+  enable-screen-grid-mode
+  var nrows/eax: int <- copy 0
+  var ncols/ecx: int <- copy 0
+  nrows, ncols <- screen-size
+  enable-keyboard-immediate-mode
+  {
+    render file, nrows, ncols
+    var key/eax: byte <- read-key
+    compare key, 0x71  # 'q'
+    loop-if-!=
+  }
+  enable-keyboard-type-mode
+  enable-screen-type-mode
+  exit-status <- copy 0
+}
+
+# decide how to lay out pages on screen
+fn render in: (addr buffered-file), nrows: int, ncols: int {
+  # hardcoded parameter: text-width
+  var toprow/eax: int <- copy 2
+  var botrow/ecx: int <- copy toprow
+  botrow <- add 0x20
+  var leftcol/edx: int <- copy 5
+  var rightcol/ebx: int <- copy leftcol
+  rightcol <- add 0x30
+  render-page in, toprow, leftcol, botrow, rightcol
+}
+
+fn render-page in: (addr buffered-file), toprow: int, leftcol: int, botrow: int, rightcol: int {
+  clear toprow, leftcol, botrow, rightcol
+  var row/ecx: int <- copy toprow
+$line-loop:  {
+    compare row, botrow
+    break-if->=
+    var col/edx: int <- copy leftcol
+    move-cursor row, col
+    {
+      compare col, rightcol
+      break-if->=
+      var c/eax: byte <- read-byte-buffered in
+      compare c, 0xffffffff  # EOF marker
+      break-if-= $line-loop
+      compare c, 0xa  # newline
+      break-if-=  # no need to print newlines
+      # print c
+      print-byte c
+      col <- increment
+      loop
+    }  # $char-loop
+    row <- increment
+    loop
+  }  # $line-loop
+}
+
+fn clear toprow: int, leftcol: int, botrow: int, rightcol: int {
+  var row/ecx: int <- copy toprow
+  {
+    compare row, botrow
+    break-if->=
+    var col/edx: int <- copy leftcol
+    move-cursor row, col
+    {
+      compare col, rightcol
+      break-if->=
+      print-string " "
+      col <- increment
+      loop
+    }
+    row <- increment
+    loop
+  }
+}
+
+fn first-arg args-on-stack: (addr array (addr array byte)) -> out/eax: (addr array byte) {
+  var args/eax: (addr array (addr array byte)) <- copy args-on-stack
+  var result/eax: (addr addr array byte) <- index args, 1
+  out <- copy *result
+}
+
+fn load-file filename: (addr array byte) -> out/esi: (addr buffered-file) {
+  var result: (handle buffered-file)
+  {
+    var tmp1/eax: (addr handle buffered-file) <- address result
+    open filename, 0, tmp1
+  }
+  var tmp2/eax: (addr buffered-file) <- lookup result
+  out <- copy tmp2
+}
+
+fn dump in: (addr buffered-file) {
+  var c/eax: byte <- read-byte-buffered in
+  compare c, 0xffffffff  # EOF marker
+  break-if-=
+  print-byte c
+  loop
+}