Split front and back end.

2 files changed, 116 insertions, 0 deletions

diff --git a/FrontEnd/src/app/views/common/alert/AlertHost.tsx b/FrontEnd/src/app/views/common/alert/AlertHost.tsx
new file mode 100644
index 00000000..c74f18e2
--- /dev/null
+++ b/FrontEnd/src/app/views/common/alert/AlertHost.tsx
@@ -0,0 +1,101 @@
+import React, { useCallback } from "react";
+import without from "lodash/without";
+import concat from "lodash/concat";
+import { useTranslation } from "react-i18next";
+import { Alert } from "react-bootstrap";
+
+import {
+  alertService,
+  AlertInfoEx,
+  kAlertHostId,
+  AlertInfo,
+} from "@/services/alert";
+
+interface AutoCloseAlertProps {
+  alert: AlertInfo;
+  close: () => void;
+}
+
+export const AutoCloseAlert: React.FC<AutoCloseAlertProps> = (props) => {
+  const { alert } = props;
+  const { dismissTime } = alert;
+
+  const { t } = useTranslation();
+
+  React.useEffect(() => {
+    const tag =
+      dismissTime === "never"
+        ? null
+        : typeof dismissTime === "number"
+        ? window.setTimeout(props.close, dismissTime)
+        : window.setTimeout(props.close, 5000);
+    return () => {
+      if (tag != null) {
+        window.clearTimeout(tag);
+      }
+    };
+  }, [dismissTime, props.close]);
+
+  return (
+    <Alert
+      className="m-3"
+      variant={alert.type ?? "primary"}
+      onClose={props.close}
+      dismissible
+    >
+      {(() => {
+        const { message } = alert;
+        if (typeof message === "function") {
+          const Message = message;
+          return <Message />;
+        } else if (typeof message === "object" && message.type === "i18n") {
+          return t(message.key);
+        } else return alert.message;
+      })()}
+    </Alert>
+  );
+};
+
+// oh what a bad name!
+interface AlertInfoExEx extends AlertInfoEx {
+  close: () => void;
+}
+
+const AlertHost: React.FC = () => {
+  const [alerts, setAlerts] = React.useState<AlertInfoExEx[]>([]);
+
+  // react guarantee that state setters are stable, so we don't need to add it to dependency list
+
+  const consume = useCallback((alert: AlertInfoEx): void => {
+    const alertEx: AlertInfoExEx = {
+      ...alert,
+      close: () => {
+        setAlerts((oldAlerts) => {
+          return without(oldAlerts, alertEx);
+        });
+      },
+    };
+    setAlerts((oldAlerts) => {
+      return concat(oldAlerts, alertEx);
+    });
+  }, []);
+
+  React.useEffect(() => {
+    alertService.registerConsumer(consume);
+    return () => {
+      alertService.unregisterConsumer(consume);
+    };
+  }, [consume]);
+
+  return (
+    <div id={kAlertHostId} className="alert-container">
+      {alerts.map((alert) => {
+        return (
+          <AutoCloseAlert key={alert.id} alert={alert} close={alert.close} />
+        );
+      })}
+    </div>
+  );
+};
+
+export default AlertHost;
diff --git a/FrontEnd/src/app/views/common/alert/alert.sass b/FrontEnd/src/app/views/common/alert/alert.sass
new file mode 100644
index 00000000..c3560b87
--- /dev/null
+++ b/FrontEnd/src/app/views/common/alert/alert.sass
@@ -0,0 +1,15 @@
+.alert-container

+  position: fixed

+  z-index: $zindex-popover

+

+@include media-breakpoint-up(sm)

+  .alert-container

+    bottom: 0

+    right: 0

+

+@include media-breakpoint-down(sm)

+  .alert-container

+    bottom: 0

+    right: 0

+    left: 0

+    text-align: center