feat: adds more functions for eval

6 files changed, 132 insertions, 34 deletions

diff --git a/TODO.norg b/TODO.norg
index 6469cb9..6ec8df2 100644
--- a/TODO.norg
+++ b/TODO.norg
@@ -1,9 +1,10 @@
 * Tasks
   - (x) Hydrate existing elements instead of re-creating
-  - ( ) `load-cssx` functions
+  - (x) `load-cssx` functions
+  - (x) `get-variable`
+  - (x) `update-variable`
   - ( ) Use css units for `delay` function
-  - ( ) `get-variable`
-  - ( ) `update-variable`
+  - ( ) Improve error messages
+  - ( ) Specify node type + attributes
   - ( ) Evaluate `calc`?
   - ( ) `list` & `tuple` data structures?
-  - ( ) Non div elements
diff --git a/examples/api/content.css b/examples/api/content.css
new file mode 100644
index 0000000..5463ba2
--- /dev/null
+++ b/examples/api/content.css
@@ -0,0 +1,26 @@
+
+#output-container-content {
+  padding: 0.5rem;
+  margin-top: 1rem;
+  border: 1px solid #888;
+
+  --cssx-children: counter-text btn-increment;
+  --count: '0';
+}
+#output-container-content::after {
+  content: "Loaded from external stylesheet";
+}
+
+#counter-text {}
+#counter-text::after { content: var(--count) }
+
+#btn-increment {
+  display: inline-block;
+  border: 1px solid gray;
+  padding: 0.3rem 0.6rem;
+  font-size: 0.9rem;
+  cursor: pointer;
+
+  --cssx-on-click: update(output-container-content, --count, '99');
+}
+#btn-increment::after { content: "Increment" }
diff --git a/examples/api/style.css b/examples/api/style.css
index 213d9e2..81eada1 100644
--- a/examples/api/style.css
+++ b/examples/api/style.css
@@ -4,17 +4,18 @@ body {
 
 #load-btn {
   display: inline-block;
-  border: 1px solid gray;
+  background: #5180e9;
+  color: #000;
   padding: 0.5rem 1rem;
   cursor: pointer;
 
   --cssx-on-click:
     add-class(output-container, 'loading')
     add-class(load-btn, 'loading')
-    delay('2000')
+    load-cssx(output-container-content, './content.css')
     remove-class(output-container, 'loading')
-    add-class(output-container, 'loaded')
     remove-class(load-btn, 'loading')
+    delay('50')
     js-eval('alert("Loaded page")')
   ;
 }
@@ -30,7 +31,4 @@ body {
 #output-container.loading::after {
   content: "Loading...";
 }
-#output-container.loaded::after {
-  content: "This content is loaded my guy";
-}
 
diff --git a/src/eval.ts b/src/eval.ts
index 76eaa21..03391c2 100644
--- a/src/eval.ts
+++ b/src/eval.ts
@@ -1,46 +1,67 @@
 import { Expr } from "./parser";
 import { match, matchString } from "./utils/adt";
 
-export type Dependencies = {
+export type EvalActions = {
   addClass(id: string, classes: string): Promise<void>
   removeClass(id: string, classes: string): Promise<void>
   delay(num: number): Promise<void>
   jsEval(js: string): Promise<any>
-  // loadCssx(id: string, url: string): Promise<string>
-  // getVarable(name: string, def?: string): Promise<string>
-  // updateVariable(id: string, varName: string, value: string): Promise<void>
+  loadCssx(id: string, url: string): Promise<string>
+  getVariable(name: string): Promise<string | undefined>
+  updateVariable(id: string, varName: string, value: string): Promise<void>
   // calculate ??
 }
 
-export const evalExpr = async (expr: Expr, deps: Dependencies): Promise<string | undefined> =>
-  match<Promise<string | undefined>, Expr>(expr, {
+type EvalValue = string | undefined | void
+
+export const evalExpr = async (expr: Expr, actions: EvalActions): Promise<EvalValue> =>
+  match<Promise<EvalValue>, Expr>(expr, {
     Call: async ({ name, args }) => {
-      await matchString(name, {
+      return matchString<Promise<EvalValue>, string>(name, {
         'add-class': async () => {
-          const id = await evalExpr(args[0], deps)
-          const classes = await evalExpr(args[1], deps)
+          const id = await evalExpr(args[0], actions)
+          const classes = await evalExpr(args[1], actions)
           if (id && classes) {
-            await deps.addClass(id, classes)
+            await actions.addClass(id, classes)
           }
         },
         'remove-class': async () => {
-          const id = await evalExpr(args[0], deps)
-          const classes = await evalExpr(args[1], deps)
+          const id = await evalExpr(args[0], actions)
+          const classes = await evalExpr(args[1], actions)
           if (id && classes) {
-            await deps.removeClass(id, classes)
+            await actions.removeClass(id, classes)
           }
         },
         'delay': async () => {
-          const num = await evalExpr(args[0], deps)
-          num && await deps.delay(parseInt(num, 10))
+          const num = await evalExpr(args[0], actions)
+          num && await actions.delay(parseInt(num, 10))
         },
         'js-eval': async () => {
-          const js = await evalExpr(args[0], deps)
-          js && await deps.jsEval(js)
+          const js = await evalExpr(args[0], actions)
+          js && await actions.jsEval(js)
+        },
+        'load-cssx': async () => {
+          const id = await evalExpr(args[0], actions)
+          const url = await evalExpr(args[1], actions)
+          if (id && url) {
+            await actions.loadCssx(id, url)
+          }
+        },
+        'var': async () => {
+          const varName = await evalExpr(args[0], actions)
+          const defaultValue = await evalExpr(args[1], actions)
+          return varName && (actions.getVariable(varName) ?? defaultValue)
+        },
+        'update': async () => {
+          const id = await evalExpr(args[0], actions)
+          const varName = await evalExpr(args[1], actions)
+          const value = await evalExpr(args[2], actions)
+          if (id && varName && value) {
+            actions.updateVariable(id, varName, value)
+          }
         },
         _: () => Promise.reject(new Error('not supposed to be here')),
       })
-      return undefined
     },
     LiteralString: async s => s,
     Identifier: async s => s,
@@ -48,3 +69,4 @@ export const evalExpr = async (expr: Expr, deps: Dependencies): Promise<string |
     _: async _ => undefined,
   })
 
+
diff --git a/src/index.ts b/src/index.ts
index 4987e65..9e9443c 100644
--- a/src/index.ts
+++ b/src/index.ts
@@ -1,4 +1,4 @@
-import { Dependencies, evalExpr } from './eval'
+import { EvalActions, evalExpr } from './eval'
 import { parse } from './parser'
 
 const UNSET_PROPERTY_VALUE = '<unset>'
@@ -33,12 +33,37 @@ const getChildrenIds = ($element: Element) => {
   return value.split(/(\s*,\s*)|\s+/g).filter(Boolean)
 }
 
-const evalDeps = (_el: Element): Dependencies => ({
+const getEvalActions = ($element: Element): EvalActions => ({
   addClass: async (id, cls) => document.getElementById(id)?.classList.add(cls),
   removeClass: async (id, cls) =>
     document.getElementById(id)?.classList.remove(cls),
   delay: (delay) => new Promise((res) => setTimeout(res, delay)),
   jsEval: async (js) => (0, eval)(js),
+  loadCssx: async (id, url) => new Promise((resolve, reject) => {
+    const $link = Object.assign(document.createElement('link'), {
+      href: url,
+      rel: 'stylesheet',
+    })
+    $link.onload = () => {
+      const $el = document.getElementById(id);
+      // NOTE: Maybe create and append to body if no root?
+      if ($el) {
+        manageElement($el)
+        resolve(id)
+      } else {
+        console.error(`[CSSX] Unable to find root for ${id}`)
+        reject(`[CSSX] Unable to find root for ${id}`)
+      }
+    }
+    document.body.appendChild($link);
+  }),
+  getVariable: async varName => getPropertyValue($element, varName),
+  updateVariable: async (targetId, varName, value) => {
+    const $el = document.getElementById(targetId)
+    if ($el) {
+      $el.style.setProperty(varName, JSON.stringify(value))
+    }
+  },
 })
 
 const handleEvents = async ($element: Element) => {
@@ -50,7 +75,7 @@ const handleEvents = async ($element: Element) => {
         console.log(`Triggered event: ${event}`)
         const exprs = parse(handlerExpr)
         for (const expr of exprs) {
-          await evalExpr(expr, evalDeps($element))
+          await evalExpr(expr, getEvalActions($element))
         }
       }
     }
@@ -73,6 +98,7 @@ const manageElement = async ($element: Element) => {
     $element.appendChild($childrenRoot)
 
     for (const id of childrenIds) {
+      // TODO: Allow adding node types other than div
       const $child =
         $childrenRoot.querySelector(`:scope > #${id}`) ??
         Object.assign(document.createElement('div'), { id })
diff --git a/tests/eval.spec.ts b/tests/eval.spec.ts
index 63062e3..8b7424f 100644
--- a/tests/eval.spec.ts
+++ b/tests/eval.spec.ts
@@ -1,10 +1,15 @@
-import { Dependencies, evalExpr } from '../src/eval'
+import { EvalActions, evalExpr } from '../src/eval'
 import { Expr } from '../src/parser'
 
 describe('eval', () => {
-  const deps: Dependencies = {
+  const deps: EvalActions = {
     addClass: jest.fn(),
     removeClass: jest.fn(),
+    delay: jest.fn(),
+    jsEval: jest.fn(),
+    loadCssx: jest.fn(),
+    getVariable: jest.fn(),
+    updateVariable: jest.fn(),
   }
 
   it('should add classes', async () => {
@@ -17,7 +22,7 @@ describe('eval', () => {
     expect(deps.addClass).toHaveBeenCalledWith('element-id', 'class-name')
   })
 
-  it('should add classes', async () => {
+  it('should remove classes', async () => {
     await evalExpr(Expr.Call({
       name: 'remove-class',
       args: [ Expr.Identifier('element-id'), Expr.LiteralString('class-name') ],
@@ -26,4 +31,24 @@ describe('eval', () => {
     expect(deps.removeClass).toHaveBeenCalledTimes(1)
     expect(deps.removeClass).toHaveBeenCalledWith('element-id', 'class-name')
   })
+
+  it('should add a delay', async () => {
+    await evalExpr(Expr.Call({
+      name: 'delay',
+      args: [ Expr.LiteralString('200') ],
+    }), deps)
+
+    expect(deps.delay).toHaveBeenCalledTimes(1)
+    expect(deps.delay).toHaveBeenCalledWith(200)
+  })
+
+  it('should get variable', async () => {
+    await evalExpr(Expr.Call({
+      name: 'var',
+      args: [ Expr.LiteralString('--my-var'), Expr.LiteralString('def value') ],
+    }), deps)
+
+    expect(deps.getVariable).toHaveBeenCalledTimes(1)
+    expect(deps.getVariable).toHaveBeenCalledWith('--my-var')
+  })
 })