Lua work

common/space_lua.ts

@@ -62,14 +62,16 @@ export class SpaceLuaEnvironment {
     for (const globalName of this.env.keys()) {
       const value = this.env.get(globalName);
       if (value instanceof LuaFunction) {
-        console.log("Now registering Lua function", globalName);
+        console.log(
+          `[Lua] Registering global function '${globalName}' (source: ${value.body.ctx.ref})`,
+        );
         scriptEnv.registerFunction({ name: globalName }, (...args: any[]) => {
           const sf = new LuaStackFrame(new LuaEnv(), value.body.ctx);
           return luaValueToJS(value.call(sf, ...args.map(jsToLuaValue)));
         });
       }
     }
-    console.log("Loaded", allScripts.length, "Lua scripts");
+    console.log("[Lua] Loaded", allScripts.length, "scripts");
   }
 }
 

common/space_lua/eval.test.ts

@@ -3,6 +3,7 @@ import {
   LuaEnv,
   LuaNativeJSFunction,
   LuaStackFrame,
+  LuaTable,
   luaValueToJS,
   singleResult,
 } from "./runtime.ts";
@@ -11,9 +12,9 @@ import type { LuaBlock, LuaFunctionCallStatement } from "./ast.ts";
 import { evalExpression, evalStatement } from "./eval.ts";
 import { luaBuildStandardEnv } from "$common/space_lua/stdlib.ts";
 
-function evalExpr(s: string, e = new LuaEnv()): any {
+function evalExpr(s: string, e = new LuaEnv(), sf?: LuaStackFrame): any {
   const node = parse(`e(${s})`).statements[0] as LuaFunctionCallStatement;
-  const sf = new LuaStackFrame(e, node.ctx);
+  sf = sf || new LuaStackFrame(e, node.ctx);
   return evalExpression(
     node.call.args[0],
     e,
@@ -277,3 +278,149 @@ Deno.test("Statement evaluation", async () => {
     luaBuildStandardEnv(),
   );
 });
+
+Deno.test("Thread local _CTX", async () => {
+  const env = new LuaEnv();
+  const threadLocal = new LuaEnv();
+  threadLocal.setLocal("threadValue", "test123");
+
+  const sf = new LuaStackFrame(threadLocal, null);
+
+  await evalBlock(
+    `
+    function test()
+      return _CTX.threadValue
+    end
+  `,
+    env,
+  );
+
+  const result = await evalExpr("test()", env, sf);
+  assertEquals(singleResult(result), "test123");
+});
+
+Deno.test("Thread local _CTX - advanced cases", async () => {
+  // Create environment with standard library
+  const env = new LuaEnv(luaBuildStandardEnv());
+  const threadLocal = new LuaEnv();
+
+  // Set up some thread local values
+  threadLocal.setLocal("user", "alice");
+  threadLocal.setLocal("permissions", new LuaTable());
+  threadLocal.get("permissions").set("admin", true);
+  threadLocal.setLocal("data", {
+    id: 123,
+    settings: { theme: "dark" },
+  });
+
+  const sf = new LuaStackFrame(threadLocal, null);
+
+  // Test 1: Nested function access
+  await evalBlock(
+    `
+    function outer()
+      local function inner()
+        return _CTX.user
+      end
+      return inner()
+    end
+  `,
+    env,
+  );
+  assertEquals(await evalExpr("outer()", env, sf), "alice");
+
+  // Test 2: Table access and modification
+  await evalBlock(
+    `
+    function checkAdmin()
+      return _CTX.permissions.admin
+    end
+
+    function revokeAdmin()
+      _CTX.permissions.admin = false
+      return _CTX.permissions.admin
+    end
+  `,
+    env,
+  );
+  assertEquals(await evalExpr("checkAdmin()", env, sf), true);
+  assertEquals(await evalExpr("revokeAdmin()", env, sf), false);
+  assertEquals(threadLocal.get("permissions").get("admin"), false);
+
+  // Test 3: Complex data structures
+  await evalBlock(
+    `
+    function getNestedData()
+      return _CTX.data.settings.theme
+    end
+    
+    function updateTheme(newTheme)
+      _CTX.data.settings.theme = newTheme
+      return _CTX.data.settings.theme
+    end
+    `,
+    env,
+  );
+  assertEquals(await evalExpr("getNestedData()", env, sf), "dark");
+  assertEquals(await evalExpr("updateTheme('light')", env, sf), "light");
+
+  // Test 4: Multiple thread locals
+  const threadLocal2 = new LuaEnv();
+  threadLocal2.setLocal("user", "bob");
+  const sf2 = new LuaStackFrame(threadLocal2, null);
+
+  await evalBlock(
+    `
+    function getUser()
+      return _CTX.user
+    end
+  `,
+    env,
+  );
+
+  // Same function, different thread contexts
+  assertEquals(await evalExpr("getUser()", env, sf), "alice");
+  assertEquals(await evalExpr("getUser()", env, sf2), "bob");
+
+  // Test 5: Async operations with _CTX
+  env.set(
+    "asyncOperation",
+    new LuaNativeJSFunction(async () => {
+      await new Promise((resolve) => setTimeout(resolve, 10));
+      return "done";
+    }),
+  );
+
+  await evalBlock(
+    `
+    function asyncTest()
+      _CTX.status = "starting"
+      local result = asyncOperation()
+      _CTX.status = "completed"
+      return _CTX.status
+    end
+  `,
+    env,
+  );
+
+  assertEquals(await evalExpr("asyncTest()", env, sf), "completed");
+  assertEquals(threadLocal.get("status"), "completed");
+
+  // Test 6: Error handling with _CTX
+  await evalBlock(
+    `
+    function errorTest()
+      _CTX.error = nil
+      local status, err = pcall(function()
+        error("test error")
+      end)
+      _CTX.error = "caught"
+      return _CTX.error
+    end
+  `,
+    env,
+  );
+
+  assertEquals(await evalExpr("errorTest()", env, sf), "caught");
+  assertEquals(threadLocal.get("error"), "caught");
+});

common/space_lua/eval.ts

@@ -334,11 +334,11 @@ function evalPrefixExpression(
         if (prefixValue instanceof Promise) {
           return prefixValue.then(async (resolvedPrefix) => {
             const args = await resolveVarargs();
-            return luaCall(resolvedPrefix, args, e.ctx, sf);
+            return luaCall(resolvedPrefix, args, e.ctx, sf.withCtx(e.ctx));
           });
         } else {
           return resolveVarargs().then((args) =>
-            luaCall(prefixValue, args, e.ctx, sf)
+            luaCall(prefixValue, args, e.ctx, sf.withCtx(e.ctx))
           );
         }
       }
@@ -409,7 +409,7 @@ const operatorsMetaMethods: Record<string, {
   "/": { metaMethod: "__div", nativeImplementation: (a, b) => a / b },
   "//": {
     metaMethod: "__idiv",
-    nativeImplementation: (a, b, ctx, sf) => Math.floor(a / b),
+    nativeImplementation: (a, b) => Math.floor(a / b),
   },
   "%": { metaMethod: "__mod", nativeImplementation: (a, b) => a % b },
   "^": { metaMethod: "__pow", nativeImplementation: (a, b) => a ** b },

common/space_lua/runtime.ts

@@ -150,6 +150,7 @@ export class LuaFunction implements ILuaFunction {
     if (!sf) {
       console.trace(sf);
     }
+    // Set _CTX to the thread local environment from the stack frame
     env.setLocal("_CTX", sf.threadLocal);
 
     // Assign the passed arguments to the parameters
@@ -271,6 +272,7 @@ export class LuaBuiltinFunction implements ILuaFunction {
   }
 
   call(sf: LuaStackFrame, ...args: LuaValue[]): Promise<LuaValue> | LuaValue {
+    // _CTX is already available via the stack frame
     return this.fn(sf, ...args);
   }
 
@@ -608,21 +610,35 @@ export class LuaRuntimeError extends Error {
       // Find the line and column
       let line = 1;
       let column = 0;
+      let lastNewline = -1;
       for (let i = 0; i < ctx.from; i++) {
         if (code[i] === "\n") {
           line++;
+          lastNewline = i;
           column = 0;
         } else {
           column++;
         }
       }
-      traceStr += `* ${
+
-        ctx.ref || "(unknown source)"
+      // Get the full line of code for context
-      } @ ${line}:${column}:\n   ${code.substring(ctx.from, ctx.to)}\n`;
+      const lineStart = lastNewline + 1;
+      const lineEnd = code.indexOf("\n", ctx.from);
+      const codeLine = code.substring(
+        lineStart,
+        lineEnd === -1 ? undefined : lineEnd,
+      );
+
+      // Add position indicator
+      const pointer = " ".repeat(column) + "^";
+
+      traceStr += `* ${ctx.ref || "(unknown source)"} @ ${line}:${column}:\n` +
+        `   ${codeLine}\n` +
+        `   ${pointer}\n`;
       current = current.parent;
     }
 
-    return `LuaRuntimeError: ${this.message} ${traceStr}`;
+    return `LuaRuntimeError: ${this.message}\nStack trace:\n${traceStr}`;
   }
 
   override toString() {

common/space_lua/stdlib.ts

@@ -72,8 +72,8 @@ const tonumberFunction = new LuaBuiltinFunction((_sf, value: LuaValue) => {
   return Number(value);
 });
 
-const errorFunction = new LuaBuiltinFunction((_sf, message: string) => {
+const errorFunction = new LuaBuiltinFunction((sf, message: string) => {
-  throw new Error(message);
+  throw new LuaRuntimeError(message, sf);
 });
 
 const pcallFunction = new LuaBuiltinFunction(
@@ -81,6 +81,9 @@ const pcallFunction = new LuaBuiltinFunction(
     try {
       return new LuaMultiRes([true, await luaCall(fn, args, sf.astCtx!, sf)]);
     } catch (e: any) {
+      if (e instanceof LuaRuntimeError) {
+        return new LuaMultiRes([false, e.message]);
+      }
       return new LuaMultiRes([false, e.message]);
     }
   },
@@ -91,9 +94,10 @@ const xpcallFunction = new LuaBuiltinFunction(
     try {
       return new LuaMultiRes([true, await fn.call(sf, ...args)]);
     } catch (e: any) {
+      const errorMsg = e instanceof LuaRuntimeError ? e.message : e.message;
       return new LuaMultiRes([
         false,
-        await luaCall(errorHandler, [e.message], sf.astCtx!, sf),
+        await luaCall(errorHandler, [errorMsg], sf.astCtx!, sf),
       ]);
     }
   },

common/space_lua/stdlib/js.ts

@@ -22,6 +22,7 @@ export const jsApi = new LuaTable({
   log: new LuaBuiltinFunction((_sf, ...args) => {
     console.log(...args);
   }),
+  stringify: new LuaBuiltinFunction((_sf, val) => JSON.stringify(val)),
   // assignGlobal: new LuaBuiltinFunction((name: string, value: any) => {
   //     (globalThis as any)[name] = value;
   // }),

common/space_lua_api.ts

@@ -56,7 +56,12 @@ function exposeDefinitions(
         if (!def.get("name")) {
           throw new Error("Name is required");
         }
-        console.log("Registering Lua command", def.get("name"));
+        const fn = def.get(1);
+        console.log(
+          `[Lua] Registering command '${
+            def.get("name")
+          }' (source: ${fn.body.ctx.ref})`,
+        );
         scriptEnv.registerCommand(
           {
             name: def.get("name"),
@@ -67,10 +72,10 @@ function exposeDefinitions(
             hide: def.get("hide"),
           } as CommandDef,
           async (...args: any[]) => {
-            const tl = new LuaEnv();
+            const tl = await buildThreadLocalEnv(system);
             const sf = new LuaStackFrame(tl, null);
             try {
-              return await def.get(1).call(sf, ...args.map(jsToLuaValue));
+              return await fn.call(sf, ...args.map(jsToLuaValue));
             } catch (e: any) {
               await handleLuaError(e, system);
             }
@@ -88,13 +93,19 @@ function exposeDefinitions(
       if (!def.get("event")) {
         throw new Error("Event is required");
       }
-      console.log("Subscribing to Lua event", def.get("event"));
+      const fn = def.get(1);
+      console.log(
+        `[Lua] Subscribing to event '${
+          def.get("event")
+        }' (source: ${fn.body.ctx.ref})`,
+      );
       scriptEnv.registerEventListener(
         { name: def.get("event") },
         async (...args: any[]) => {
-          const sf = new LuaStackFrame(new LuaEnv(), null);
+          const tl = await buildThreadLocalEnv(system);
+          const sf = new LuaStackFrame(tl, null);
           try {
-            return await def.get(1).call(sf, ...args.map(jsToLuaValue));
+            return await fn.call(sf, ...args.map(jsToLuaValue));
           } catch (e: any) {
             await handleLuaError(e, system);
           }
@@ -104,6 +115,16 @@ function exposeDefinitions(
   );
 }
 
+async function buildThreadLocalEnv(system: System<any>) {
+  const tl = new LuaEnv();
+  const currentPageMeta = await system.localSyscall(
+    "editor.getCurrentPageMeta",
+    [],
+  );
+  tl.setLocal("pageMeta", currentPageMeta);
+  return tl;
+}
+
 async function handleLuaError(e: any, system: System<any>) {
   console.error(
     "Lua eval exception",

common/template/render.ts

@@ -79,7 +79,10 @@ async function renderExpressionDirective(
     variables,
     functionMap,
   );
+  return renderExpressionResult(result);
+}
 
+export function renderExpressionResult(result: any): string {
   if (
     Array.isArray(result) && result.length > 0 && typeof result[0] === "object"
   ) {

plug-api/syscalls/editor.ts

@@ -1,4 +1,4 @@
-import type { UploadFile } from "../types.ts";
+import type { PageMeta, UploadFile } from "../types.ts";
 import { syscall } from "../syscall.ts";
 import type { PageRef } from "../lib/page_ref.ts";
 import type { FilterOption } from "@silverbulletmd/silverbullet/type/client";
@@ -17,6 +17,14 @@ export function getCurrentPage(): Promise<string> {
   return syscall("editor.getCurrentPage");
 }
 
+/**
+ * Returns the meta data of the page currently open in the editor.
+ * @returns the current page meta data
+ */
+export function getCurrentPageMeta(): Promise<PageMeta | undefined> {
+  return syscall("editor.getCurrentPageMeta");
+}
+
 /**
  * Returns the full text of the currently open page
  */

web/cm_plugins/lua_directive.ts

@@ -43,13 +43,13 @@ export function luaDirectivePlugin(client: Client) {
         }
 
         const text = state.sliceDoc(node.from + 2, node.to - 1);
-
+        const currentPageMeta = client.ui.viewState.currentPageMeta;
         widgets.push(
           Decoration.widget({
             widget: new LuaWidget(
               node.from,
               client,
-              `lua:${text}`,
+              `lua:${text}:${currentPageMeta?.name}`,
               text,
               async (bodyText) => {
                 try {
@@ -58,14 +58,22 @@ export function luaDirectivePlugin(client: Client) {
                     (parsedLua.statements[0] as LuaFunctionCallStatement).call
                       .args[0];
 
-                  const sf = new LuaStackFrame(new LuaEnv(), expr.ctx);
+                  const tl = new LuaEnv();
-                  return luaValueToJS(
+                  tl.setLocal("pageMeta", currentPageMeta);
+                  const sf = new LuaStackFrame(tl, expr.ctx);
+                  const threadLocalizedEnv = new LuaEnv(
+                    client.clientSystem.spaceLuaEnv.env,
+                  );
+                  threadLocalizedEnv.setLocal("_CTX", tl);
+                  const result = luaValueToJS(
                     await evalExpression(
                       expr,
-                      client.clientSystem.spaceLuaEnv.env,
+                      threadLocalizedEnv,
                       sf,
                     ),
                   );
+                  // console.log("Result:", result);
+                  return result;
                 } catch (e: any) {
                   if (e instanceof LuaRuntimeError) {
                     if (e.sf.astCtx) {

web/cm_plugins/lua_widget.ts

@@ -11,6 +11,7 @@ import { extendedMarkdownLanguage } from "$common/markdown_parser/parser.ts";
 import { renderToText } from "@silverbulletmd/silverbullet/lib/tree";
 import { activeWidgets } from "./markdown_widget.ts";
 import { attachWidgetEventHandlers } from "./widget_util.ts";
+import { renderExpressionResult } from "$common/template/render.ts";
 
 export type LuaWidgetCallback = (
   bodyText: string,
@@ -97,10 +98,15 @@ export class LuaWidget extends WidgetType {
         this.cacheKey,
         { height: div.clientHeight, html },
       );
-    } else if (widgetContent.markdown) {
+    } else {
+      // If there is a markdown key, use it, otherwise render the objects as a markdown table
+      let mdContent = widgetContent.markdown;
+      if (!mdContent) {
+        mdContent = renderExpressionResult(widgetContent);
+      }
       let mdTree = parse(
         extendedMarkdownLanguage,
-        widgetContent.markdown!,
+        mdContent,
       );
       mdTree = await this.client.clientSystem.localSyscall(
         "system.invokeFunction",
@@ -187,8 +193,8 @@ export class LuaWidget extends WidgetType {
   override eq(other: WidgetType): boolean {
     return (
       other instanceof LuaWidget &&
-      other.bodyText === this.bodyText && other.cacheKey === this.cacheKey &&
+      other.bodyText === this.bodyText && other.cacheKey === this.cacheKey
-      this.from === other.from
+      // &&  this.from === other.from
     );
   }
 }

web/syscalls/editor.ts

@@ -12,7 +12,7 @@ import { EditorView } from "@codemirror/view";
 import { getCM as vimGetCm, Vim } from "@replit/codemirror-vim";
 import type { SysCallMapping } from "$lib/plugos/system.ts";
 import type { FilterOption } from "@silverbulletmd/silverbullet/type/client";
-import type { UploadFile } from "../../plug-api/types.ts";
+import type { PageMeta, UploadFile } from "../../plug-api/types.ts";
 import type { PageRef } from "@silverbulletmd/silverbullet/lib/page_ref";
 import { openSearchPanel } from "@codemirror/search";
 import { diffAndPrepareChanges } from "../cm_util.ts";
@@ -22,6 +22,9 @@ export function editorSyscalls(client: Client): SysCallMapping {
     "editor.getCurrentPage": (): string => {
       return client.currentPage;
     },
+    "editor.getCurrentPageMeta": (): PageMeta | undefined => {
+      return client.ui.viewState.currentPageMeta;
+    },
     "editor.getText": () => {
       return client.editorView.state.sliceDoc();
     },

website/Space Lua.md

@@ -81,7 +81,9 @@ You can listen to events using `define_event_listener`:
 define_event_listener {
   event = "my-custom-event";
   function(e)
-    editor.flash_notification("Custom triggered: " .. e.data.name)
+    editor.flash_notification("Custom triggered: "
+       .. e.data.name
+       .. " on page " .. _CTX.pageMeta.name)
   end
 }
 ```
@@ -106,6 +108,11 @@ Template:
 Here's a greeting: {{greet_me("Pete")}}
 ```
 
+# Thread locals
+There’s a magic `_CTX` global variable available from which you can access useful context-specific value. Currently the following keys are available:
+
+* `_CTX.pageMeta` contains a reference to the loaded page metadata (can be `nil` when not yet loaded)
+
 # API
 Lua APIs, which should be (roughly) implemented according to the Lua standard.
 * `print`