load forth from server

3 files changed, 41 insertions, 22 deletions

diff --git a/site/index.html b/site/index.html
index 6583568..5939d37 100644
--- a/site/index.html
+++ b/site/index.html
@@ -10,20 +10,13 @@
 
     <div id='editor'>
       <div id='code'>
+        <select id='src-select'>
+          <option>fac.fs</option>
+          <option>slo-fac.fs</option>
+        </select>
         <button id='compile'>compile</button>
         <br>
-        <div id='src' contenteditable='plaintext-only'>: fac ( n -- n )
-	dup		( n n )
-	1 > if		( n flag )
-		dup	( n n )
-		1 -		( n n-1 )
-		fac		( n fac-n )
-		*		( n )
-	then		( n )
-;
-
-5 fac
-drop</div>
+        <div id='src' contenteditable='plaintext-only'></div>
       </div>
 
       <div id='state-container'>
diff --git a/site/main.mjs b/site/main.mjs
index 3add1fe..22d1f96 100644
--- a/site/main.mjs
+++ b/site/main.mjs
@@ -85,12 +85,38 @@ function tick(vm) {
     renderTextHighlight(vm);
 }
 
+function loadForth(taintedPath) {
+    // ascii only + ‘-’, ‘_’, ‘.’, and ‘/’, but no ‘../’
+    const path =
+        taintedPath
+            .replace(/[^-_A-Za-z./]/g, '')
+            .replace(/\.\.\//g, '');
+    fetch(`./samples/${path}`)
+        .then(resp => {
+            if (!resp.ok) {
+                throw `http status ${resp.status}`
+            }
+            return resp.text()
+        })
+        .then(text => {
+            document.querySelector('#src').textContent = text;
+        })
+        .catch(e => {
+            console.error(`couldn't fetch ‘${path}’`, e);
+        });
+}
+
 async function loaded() {
     console.debug('running init');
     const mod = await init();
     console.debug('init done', mod);
     const vm = make_vm();
 
+    document.querySelectorAll('#src-select').forEach(async sel => {
+        sel.onchange = _ => loadForth(sel.value);
+        loadForth(sel.value);
+    });
+
     document.querySelector('#compile').onclick = e => {
         console.debug('compile clicked', e);
 
diff --git a/site/samples/slo-fac.fs b/site/samples/slo-fac.fs
index 0ba50ca..1de4dc8 100644
--- a/site/samples/slo-fac.fs
+++ b/site/samples/slo-fac.fs
@@ -8,19 +8,19 @@
 \ and be something nice to look at with blinken
 
 : count-to ( n -- n n-1 ... 1 )
-  dup
-  1 > if
-    dup 1 - count-to
-  then
+    dup
+    1 > if
+        dup 1 - count-to
+    then
 ;
 
 : stack-mul ( n-x ... n x -- v )
-  dup
-  1 > if
-    rot rot * swap 1 - stack-mul
-  else
-    drop
-  then
+    dup
+    1 > if
+        rot rot * swap 1 - stack-mul
+    else
+        drop
+    then
 ;
 
 5 count-to