feat: Ability to delete account for administrators (#1874)

## Description

Add account delete option in the user account settings.

Fixes #1555 

## Type of change

- [ ] New feature (non-breaking change which adds functionality)


![image](https://user-images.githubusercontent.com/40784971/110349673-edcc5200-8058-11eb-8ded-a31d15aa0759.png)

![image](https://user-images.githubusercontent.com/40784971/110349778-0c324d80-8059-11eb-9291-abfbffedde5e.png)


## Checklist:

- [ ] My code follows the style guidelines of this project
- [ ] I have performed a self-review of my own code
- [ ] I have commented on my code, particularly in hard-to-understand
areas
- [ ] I have made corresponding changes to the documentation
- [ ] My changes generate no new warnings
- [ ] I have added tests that prove my fix is effective or that my
feature works
- [ ] New and existing unit tests pass locally with my changes
- [ ] Any dependent changes have been merged and published in downstream
modules

---------

Co-authored-by: Sojan Jose <sojan@pepalo.com>
Co-authored-by: Sojan Jose <sojan.official@gmail.com>
Co-authored-by: Muhsin Keloth <muhsinkeramam@gmail.com>

enterprise/app/controllers/enterprise/api/v1/accounts_controller.rb

@@ -2,7 +2,7 @@ class Enterprise::Api::V1::AccountsController < Api::BaseController
   include BillingHelper
   before_action :fetch_account
   before_action :check_authorization
-  before_action :check_cloud_env, only: [:limits]
+  before_action :check_cloud_env, only: [:limits, :toggle_deletion]
 
   def subscription
     if stripe_customer_id.blank? && @account.custom_attributes['is_creating_customer'].blank?
@@ -42,13 +42,26 @@ class Enterprise::Api::V1::AccountsController < Api::BaseController
     render_invalid_billing_details
   end
 
+  def toggle_deletion
+    action_type = params[:action_type]
+
+    case action_type
+    when 'delete'
+      mark_for_deletion
+    when 'undelete'
+      unmark_for_deletion
+    else
+      render json: { error: 'Invalid action_type. Must be either "delete" or "undelete"' }, status: :unprocessable_entity
+    end
+  end
+
+  private
+
   def check_cloud_env
     installation_config = InstallationConfig.find_by(name: 'DEPLOYMENT_ENV')
     render json: { error: 'Not found' }, status: :not_found unless installation_config&.value == 'cloud'
   end
 
-  private
-
   def default_limits
     {
       'conversation' => {},
@@ -67,6 +80,24 @@ class Enterprise::Api::V1::AccountsController < Api::BaseController
     @account.custom_attributes['stripe_customer_id']
   end
 
+  def mark_for_deletion
+    reason = 'manual_deletion'
+
+    if @account.mark_for_deletion(reason)
+      render json: { message: 'Account marked for deletion' }, status: :ok
+    else
+      render json: { message: @account.errors.full_messages.join(', ') }, status: :unprocessable_entity
+    end
+  end
+
+  def unmark_for_deletion
+    if @account.unmark_for_deletion
+      render json: { message: 'Account unmarked for deletion' }, status: :ok
+    else
+      render json: { message: @account.errors.full_messages.join(', ') }, status: :unprocessable_entity
+    end
+  end
+
   def render_invalid_billing_details
     render_could_not_create_error('Please subscribe to a plan before viewing the billing details')
   end