From 5f5579e1682fbcea3340a036ef57684cacb835e4 Mon Sep 17 00:00:00 2001
From: Kartik Agaram <vc@akkartik.com>
Date: Sun, 25 Oct 2020 21:33:24 -0700
Subject: [PATCH] 7107 - tile: file handles

---
 apps/tile/data.mu        |  1 +
 apps/tile/environment.mu | 20 +++++++++++++++++++-
 apps/tile/rpn.mu         | 32 ++++++++++++++++++++++++++++++++
 apps/tile/value-stack.mu | 13 +++++++++++++
 4 files changed, 65 insertions(+), 1 deletion(-)

diff --git a/apps/tile/data.mu b/apps/tile/data.mu
index 7575461c..8a23fea9 100644
--- a/apps/tile/data.mu
+++ b/apps/tile/data.mu
@@ -38,6 +38,7 @@ type value {
   int-data: int  # if type = 0
   text-data: (handle array byte)  # if type = 1
   array-data: (handle array int)  # if type = 2
+  file-data: (handle buffered-file)  # if type = 3
 }
 
 type table {
diff --git a/apps/tile/environment.mu b/apps/tile/environment.mu
index e37b32ba..757e62b9 100644
--- a/apps/tile/environment.mu
+++ b/apps/tile/environment.mu
@@ -778,6 +778,14 @@ fn bound-function? w: (addr word), functions-ah: (addr handle function) -> resul
   subresult <- word-equal? w, "len"
   compare subresult, 0  # false
   break-if-!=
+  # if w == "open" return true
+  subresult <- word-equal? w, "open"
+  compare subresult, 0  # false
+  break-if-!=
+  # if w == "read" return true
+  subresult <- word-equal? w, "read"
+  compare subresult, 0  # false
+  break-if-!=
   # return w in functions
   var out-h: (handle function)
   var out/eax: (addr handle function) <- address out-h
@@ -1372,6 +1380,16 @@ fn render-column screen: (addr screen), functions: (addr handle function), bindi
             render-array screen, val
             break $render-column:render-value
           }
+          {
+            compare *val-type, 3  # file
+            break-if-!=
+            var val-ah/eax: (addr handle buffered-file) <- get val-addr, file-data
+            var val/eax: (addr buffered-file) <- lookup *val-ah
+            start-color screen, 0, 7
+            # TODO
+            print-string screen, " FILE "
+            break $render-column:render-value
+          }
           # render ints by default for now
           var val-addr2/eax: (addr int) <- get val-addr, int-data
           render-integer screen, *val-addr2, max-width
@@ -1498,7 +1516,7 @@ fn clear-canvas _env: (addr environment) {
   print-string screen, "functions:"
   start-col <- add 2
   move-cursor screen, 2, start-col
-  print-string screen, "+ - * len"
+  print-string screen, "+ - * len open read"
   # currently defined functions
   var row/ebx: int <- copy 5
   var functions/esi: (addr handle function) <- get env, functions
diff --git a/apps/tile/rpn.mu b/apps/tile/rpn.mu
index ef53bb7e..c206e997 100644
--- a/apps/tile/rpn.mu
+++ b/apps/tile/rpn.mu
@@ -102,6 +102,38 @@ fn evaluate functions: (addr handle function), bindings: (addr table), scratch:
           break $evaluate:process-word
         }
       }
+      {
+        var is-open?/eax: boolean <- stream-data-equal? curr-stream, "open"
+        compare is-open?, 0
+        break-if-=
+        # pop target-val from out
+        var out2/esi: (addr value-stack) <- copy out
+        var top-addr/ecx: (addr int) <- get out2, top
+        compare *top-addr, 0
+        break-if-<=
+        var data-ah/eax: (addr handle array value) <- get out2, data
+        var data/eax: (addr array value) <- lookup *data-ah
+        var top/edx: int <- copy *top-addr
+        top <- decrement
+        var dest-offset/edx: (offset value) <- compute-offset data, top
+        var target-val/edx: (addr value) <- index data, dest-offset
+        # check target-val is a string
+        var target-type-addr/eax: (addr int) <- get target-val, type
+        compare *target-type-addr, 1  # string
+        break-if-!=
+        # open target-val as a filename and save the handle in target-val
+        var src-ah/eax: (addr handle array byte) <- get target-val, text-data
+        var src/eax: (addr array byte) <- lookup *src-ah
+        var result-ah/ecx: (addr handle buffered-file) <- get target-val, file-data
+        open src, 0, result-ah  # write? = false
+        # save result into target-val
+        var type-addr/eax: (addr int) <- get target-val, type
+        copy-to *type-addr, 3  # file
+        var target-string-ah/eax: (addr handle array byte) <- get target-val, text-data
+        var empty: (handle array byte)
+        copy-handle empty, target-string-ah
+        break $evaluate:process-word
+      }
       # if curr-stream defines a binding, save top of stack to bindings
       {
         var done?/eax: boolean <- stream-empty? curr-stream
diff --git a/apps/tile/value-stack.mu b/apps/tile/value-stack.mu
index dbe25b74..2eae94d3 100644
--- a/apps/tile/value-stack.mu
+++ b/apps/tile/value-stack.mu
@@ -176,6 +176,19 @@ fn value-stack-max-width _self: (addr value-stack) -> result/eax: int {
       break-if-<=
       copy-to out, w
     }
+    {
+      compare *type, 3  # file handle
+      break-if-!=
+      var f-ah/eax: (addr handle buffered-file) <- get g, file-data
+      var f/eax: (addr buffered-file) <- lookup *f-ah
+      compare f, 0
+      break-if-=
+      # TODO
+      var w/eax: int <- copy 4
+      compare w, out
+      break-if-<=
+      copy-to out, w
+    }
     i <- increment
     loop
   }