feat(call-to-action): add support for multiple actions

apps/client/src/widgets/dialogs/call_to_action.tsx

@@ -1,3 +1,4 @@
+import { useMemo, useState } from "preact/hooks";
 import Button from "../react/Button";
 import Modal from "../react/Modal";
 import ReactBasicWidget from "../react/ReactBasicWidget";
@@ -10,26 +11,52 @@ interface CallToAction {
     }[];
 }
 
-function CallToActionDialogComponent() {
-    const CallToAction: CallToAction = {
+const CALL_TO_ACTIONS: CallToAction[] = [
+    {
         title: "Background effects are now stable",
         message: "On Windows devices, background effects are now fully stable. The background effects adds a touch of color to the user interface by blurring the background behind it. This technique is also used in other applications such as Windows Explorer.",
         buttons: [
             { text: "Enable background effects" }
         ]
-    };
+    },
+    {
+        title: "TriliumNext theme is now stable",
+        message: "For a while now, we've been working on a new theme to give the application a more modern look.",
+        buttons: [
+            { text: "Switch to the TriliumNext theme"}
+        ]
+    }
+];
+
+function CallToActionDialogComponent() {
+    const [ activeIndex, setActiveIndex ] = useState(0);
+    const [ shown, setShown ] = useState(true);
+    const activeItem = CALL_TO_ACTIONS[activeIndex];
+
+    function goToNext() {
+        if (activeIndex + 1 < CALL_TO_ACTIONS.length) {
+            setActiveIndex(activeIndex + 1);
+        } else {
+            setShown(false);
+        }
+    }
 
     return (
         <Modal
             title="New features"
-            show={true}
-        >
-            <h4>{CallToAction.title}</h4>
-            <p>{CallToAction.message}</p>
-
-            {CallToAction.buttons.map((button) =>
-                <Button text={button.text} />   
+            show={shown}
+            footerAlignment="between"
+            footer={<>
+                <Button text="Dismiss" onClick={goToNext} />
+                {activeItem.buttons.map((button) =>
+                    <Button text={button.text} onClick={() => {
+                        goToNext();
+                    }}/>   
                 )}
+            </>}
+        >
+            <h4>{activeItem.title}</h4>
+            <p>{activeItem.message}</p>
         </Modal>
     )
 }