Update README with content of the old plugin

README.md

@@ -10,16 +10,142 @@ This is where your description should go. Limit it to a paragraph or two. Consid
 
 ## Installation
 
-1. Run `composer require flux-se/sylius-stripe-plugin`.
-
-2. Import configuration
+1. Install the plugin ()
+    ```shell
+    composer require flux-se/sylius-stripe-plugin:dev-main
+    ```
+2. Enable this plugin :
+    ```php
+    <?php
+    
+    # config/bundles.php
+    
+    return [
+        // ...
+        FluxSE\SyliusStripePlugin\FluxSESyliusStripePlugin::class => ['all' => true],
+        // ...
+    ];
+    ```
+3. Import configuration
     ```yaml
-    # config/packages/_sylius.yaml
+    # config/packages/flux_se_sylius_stripe.yaml
 
     imports:
     # ...
     - { resource: "@FluxSESyliusStripePlugin/config/config.yaml" }
     ```
+## Configuration
+
+ - Go to the admin area.
+ - Log in.
+ - Click on the left menu item "CONFIGURATION > Payment methods".
+ - Create a new payment method type "Stripe (Checkout)" or "Stripe (Web Elements)":
+   
+   ![Create a new payment method][docs-assets-create-payment-method]
+ - The next chapter will explain how to fill the payment method creation form.
+ 
+### Payment Method configuration
+
+A form will be displayed, fill-in the required fields :
+
+#### 1. The "code" field (ex: "my_shop_stripe_checkout").
+
+> 💡 The code will be the `gateway name`, it will be necessary to build the right webhook URL later
+> (see [Webhook key](#webhook-key) section for more info).
+
+#### 2. Choose which channels this payment method will be affected to.
+
+#### 3. The gateway configuration ([need info from here](#api-keys)) :
+
+![Gateway Configuration][docs-assets-gateway-configuration]
+
+![Gateway Configuration][docs-assets-gateway-configuration-authorize]
+
+> _📖 NOTE1: You can add as many webhook secret keys as you need here, however generic usage needs only one._
+
+> _📖 NOTE2: the screenshot contains false test credentials._
+
+#### 4. Give to this payment method a display name (and a description) for each language you need.
+
+Finally, click on the "Create" button to save your new payment method.
+
+### API keys
+
+Get your `publishable_key` and your `secret_key` on your Stripe dashboard :
+
+https://dashboard.stripe.com/test/apikeys
+
+### Webhook key
+
+Got to :
+
+https://dashboard.stripe.com/test/webhooks
+
+Then create a new endpoint with those events:
+
+| Gateway | `stripe_checkout` | `stripe_web_elements` |
+|-|-|-|
+| Webhook events |  - `checkout.session.completed`<br> - `checkout.session.async_payment_failed`<br> - `checkout.session.async_payment_succeeded`<br> - `checkout.session.expired`<br> - `setup_intent.canceled` (⚠️ Only when using `setup` mode)<br> - `setup_intent.succeeded`  (⚠️ Only when using `setup` mode) |  - `payment_intent.canceled`<br> - `payment_intent.succeeded`<br> - `setup_intent.canceled` (⚠️ Only when using `setup` mode)<br> - `setup_intent.succeeded`  (⚠️ Only when using `setup` mode) |
+
+
+The URL to fill is the route named `sylius_payment_method_notify` with the `{code}`
+param equal to the `payment method code`, here is an example :
+
+```
+https://localhost/payment-methods/my_shop_stripe_checkout
+```
+
+> 📖 As you can see in this example the URL is dedicated to `localhost`, you will need to provide to
+> Stripe a public host name to get the webhooks working.
+
+> 📖 Use this command to know the exact structure of `sylius_payment_method_notify` route
+>
+> ```shell
+> bin/console debug:router sylius_payment_method_notify
+> ```
+
+### Test or dev environment
+
+Webhooks are triggered by Stripe on their server to your server.
+If the server is into a private network, Stripe won't be allowed to reach your server.
+
+Stripe provide an alternate way to catch those webhook events, you can use
+`Stripe cli` : https://stripe.com/docs/stripe-cli
+Follow the link and install `Stripe cli`, then use those command line to get
+your webhook key :
+
+First login to your Stripe account (needed every 90 days) :
+
+```shell
+stripe login
+```
+
+Then start to listen for the Stripe events (minimal ones are used here), forwarding request to your local server :
+
+ 1. Example with `my_shop_stripe_checkout` as payment method code:
+    ```shell
+    stripe listen \
+       --events checkout.session.completed,checkout.session.async_payment_failed,checkout.session.async_payment_succeeded,checkout.session.expired \
+       --forward-to https://localhost/payment/notify/unsafe/my_shop_stripe_checkout
+    ```
+ 2. Example with `my_shop_stripe_web_elements` as payment method code:
+    ```shell
+    stripe listen \
+       --events payment_intent.canceled,payment_intent.succeeded \
+       --forward-to https://localhost/payment/notify/unsafe/my_shop_stripe_web_elements
+    ```
+
+> 💡 Replace --forward-to argument value with the right one you need.
+
+When the command finishes, a webhook secret key is displayed, copy it to your
+Payment method configuration edit form in the Sylius admin.
+
+> ⚠️ Using the command `stripe trigger checkout.session.completed` will always result in a `500 error`,
+> because the test object will not embed any usable metadata.
+
+## API (Sylius Api Platform)
+
+@todo
 
 ## Changelog