Adapt screen to check code owners to this being a self service now

With change I25cff9f08 we opened the Check Code Owner REST endpoint for
normal users. Adapt the screen to check code owners to this now:

* Remove the note saying that administrator permissions are needed.
* Separate options that everyone can use from admin only options
* Disable the input fields for admin only options if the current user is
  not an admin

Bug: Google b/345161989
Change-Id: I638ddce265afe916c3874c8432d992cb620689d8
Signed-off-by: Edwin Kempin <ekempin@google.com>

web/gr-check-code-owner.ts

diff --git a/web/gr-check-code-owner.ts b/web/gr-check-code-owner.ts
index cba304f..7214527 100644
--- a/web/gr-check-code-owner.ts
+++ b/web/gr-check-code-owner.ts
@@ -25,6 +25,12 @@
   }
 }
 
+// https://gerrit-review.googlesource.com/Documentation/rest-api-accounts.html#capability-info
+export interface AccountCapabilityInfo {
+  administrateServer: boolean;
+  'code-owners-checkCodeOwner': boolean;
+}
+
 @customElement('gr-check-code-owner')
 export class GrCheckCodeOwner extends LitElement {
   @query('#projectInput')
@@ -54,6 +60,9 @@
   @state()
   isChecking = false;
 
+  @state()
+  hasAdminPermissions = false;
+
   static override get styles() {
     return [
       window.Gerrit.styles.font as CSSResult,
@@ -84,14 +93,7 @@
           Checks the code ownership of a user for a path in a branch, see
           <a href="${window.CANONICAL_PATH || ''}/plugins/code-owners/Documentation/rest-api.html#check-code-owner" target="_blank">documentation<a/>.
         </p>
-        <p>
-          Requires that the caller has the
-          <a href="${window.CANONICAL_PATH || ''}/plugins/code-owners/Documentation/rest-api.html#checkCodeOwner" target="_blank">Check Code Owner</a>
-          or the
-          <a href="${window.CANONICAL_PATH || ''}/Documentation/access-control.html#capability_administrateServer" target="_blank">Administrate Server</a>
-          global capability.
-        </p>
-        <p>All fields, except the 'Calling User' field, are required.</p>
+        <p>Required fields:</p>
         <fieldset>
           <section>
             <span class="title">
@@ -162,6 +164,13 @@
               />
             </span>
           </section>
+        </fieldset>
+        <p>Admin options (usage requires having the
+          <a href="${window.CANONICAL_PATH || ''}/plugins/code-owners/Documentation/rest-api.html#checkCodeOwner" target="_blank">Check Code Owner</a>
+          or the
+          <a href="${window.CANONICAL_PATH || ''}/Documentation/access-control.html#capability_administrateServer" target="_blank">Administrate Server</a>
+          global capability):
+        <fieldset>
           <section>
             <span class="title">
               <gr-tooltip-content
@@ -175,6 +184,7 @@
               <input
                 id="userInput"
                 type="text"
+                ?disabled=${!this.hasAdminPermissions}
                 @input=${this.validateData}
               />
             </span>
@@ -205,6 +215,22 @@
     `;
   }
 
+  override connectedCallback() {
+    super.connectedCallback();
+    this.checkAdminPermissions();
+  }
+
+  private async checkAdminPermissions() {
+    await this.plugin
+      .restApi()
+      .get<AccountCapabilityInfo>('/accounts/self/capabilities/')
+      .then(capabilities => {
+        this.hasAdminPermissions = capabilities &&
+          (capabilities['administrateServer'] ||
+            capabilities['code-owners-checkCodeOwner']);
+      });
+  }
+
   private validateData() {
     this.dataValid =
       this.validateHasValue(this.projectInput.value) &&