[web] Create the modals that will allow the user to confirm role dele…

…tion

Summary:
This should be the final stack in the entire roles project. This is the client-side logic for `web` to handle role deletion. Per the designs, the warning message is the same as on `native`, with
either a generic deletion message if nobody is assigned the role or a more specific one if members have this custom role.

[[ https://linear.app/comm/issue/ENG-4432/create-the-modals-that-will-allow-the-user-to-confirm-role-deletion | ENG-4432 ]]

Depends on D8624

Test Plan:
Verified that the modal appears as expected for roles with and without members, and pressing the delete button actually deletes

{F653374}

Reviewers: atul, ginsu

Reviewed By: atul

Subscribers: tomek, ashoat

Differential Revision: https://phab.comm.dev/D8625

web/roles/delete-role-modal.css

@@ -0,0 +1,20 @@
+.roleDeletionText {
+  color: var(--modal-fg);
+  font-size: var(--m-font-14);
+  padding: 16px 32px;
+}
+
+.buttonsContainer {
+  display: flex;
+  flex-direction: row;
+  justify-content: flex-end;
+  padding: 16px 32px;
+}
+
+.cancelButton {
+  width: 100px;
+}
+
+.deleteRoleButton {
+  margin-left: 8px;
+}

web/roles/delete-role-modal.react.js

@@ -0,0 +1,111 @@
+// @flow
+
+import * as React from 'react';
+
+import {
+  deleteCommunityRole,
+  deleteCommunityRoleActionTypes,
+} from 'lib/actions/thread-actions.js';
+import { useModalContext } from 'lib/components/modal-provider.react.js';
+import { createLoadingStatusSelector } from 'lib/selectors/loading-selectors.js';
+import { useRoleMemberCountsForCommunity } from 'lib/shared/thread-utils.js';
+import type { LoadingStatus } from 'lib/types/loading-types.js';
+import type { ThreadInfo } from 'lib/types/thread-types.js';
+import {
+  useServerCall,
+  useDispatchActionPromise,
+} from 'lib/utils/action-utils.js';
+import { constructRoleDeletionMessagePrompt } from 'lib/utils/role-utils.js';
+
+import css from './delete-role-modal.css';
+import Button, { buttonThemes } from '../components/button.react.js';
+import LoadingIndicator from '../loading-indicator.react.js';
+import Modal from '../modals/modal.react.js';
+import { useSelector } from '../redux/redux-utils.js';
+
+const deleteRoleLoadingStatusSelector = createLoadingStatusSelector(
+  deleteCommunityRoleActionTypes,
+);
+
+type DeleteRoleModalProps = {
+  +threadInfo: ThreadInfo,
+  +defaultRoleID: string,
+  +roleID: string,
+};
+
+function DeleteRoleModal(props: DeleteRoleModalProps): React.Node {
+  const { threadInfo, defaultRoleID, roleID } = props;
+  const { popModal } = useModalContext();
+
+  const callDeleteCommunityRole = useServerCall(deleteCommunityRole);
+  const dispatchActionPromise = useDispatchActionPromise();
+
+  const deleteRoleLoadingStatus: LoadingStatus = useSelector(
+    deleteRoleLoadingStatusSelector,
+  );
+
+  const roleNamesToMemberCounts = useRoleMemberCountsForCommunity(threadInfo);
+  const roleName = threadInfo.roles[roleID].name;
+  const memberCount = roleNamesToMemberCounts[roleName];
+  const defaultRoleName = threadInfo.roles[defaultRoleID].name;
+
+  const message = constructRoleDeletionMessagePrompt(
+    defaultRoleName,
+    memberCount,
+  );
+
+  const onDeleteRole = React.useCallback(() => {
+    dispatchActionPromise(
+      deleteCommunityRoleActionTypes,
+      (async () => {
+        const response = await callDeleteCommunityRole({
+          community: threadInfo.id,
+          roleID: roleID,
+        });
+        popModal();
+        return response;
+      })(),
+    );
+  }, [
+    callDeleteCommunityRole,
+    dispatchActionPromise,
+    roleID,
+    threadInfo.id,
+    popModal,
+  ]);
+
+  const deleteButtonContent = React.useMemo(() => {
+    if (deleteRoleLoadingStatus === 'loading') {
+      return (
+        <LoadingIndicator status={deleteRoleLoadingStatus} size="medium" />
+      );
+    }
+    return 'Yes, delete role';
+  }, [deleteRoleLoadingStatus]);
+
+  return (
+    <Modal name="Delete role" onClose={popModal} size="large">
+      <div className={css.roleDeletionText}>{message}</div>
+      <div className={css.buttonsContainer}>
+        <Button
+          variant="outline"
+          className={css.cancelButton}
+          buttonColor={buttonThemes.outline}
+          onClick={popModal}
+        >
+          Cancel
+        </Button>
+        <Button
+          variant="filled"
+          className={css.deleteRoleButton}
+          buttonColor={buttonThemes.danger}
+          onClick={onDeleteRole}
+        >
+          {deleteButtonContent}
+        </Button>
+      </div>
+    </Modal>
+  );
+}
+
+export default DeleteRoleModal;

web/roles/role-actions-menu.react.js

@@ -10,6 +10,7 @@ import type { ThreadInfo } from 'lib/types/thread-types.js';
 import { useRoleDeletableAndEditableStatus } from 'lib/utils/role-utils.js';
 
 import CreateRolesModal from './create-roles-modal.react.js';
+import DeleteRoleModal from './delete-role-modal.react.js';
 import css from './role-actions-menu.css';
 import MenuItem from '../components/menu-item.react.js';
 import Menu from '../components/menu.react.js';
@@ -63,7 +64,15 @@ function RoleActionsMenu(props: RoleActionsMenuProps): React.Node {
       threadInfo,
     ],
   );
-  const openDeleteRoleModal = React.useCallback(() => {}, []);
+  const openDeleteRoleModal = React.useCallback(() => {
+    pushModal(
+      <DeleteRoleModal
+        threadInfo={threadInfo}
+        defaultRoleID={defaultRoleID}
+        roleID={existingRoleID}
+      />,
+    );
+  }, [existingRoleID, pushModal, threadInfo, defaultRoleID]);
 
   const menuItems = React.useMemo(() => {
     const availableOptions = [];