Allow reliable handover code copy and paste

assets/js/hooks.js

@@ -204,6 +204,70 @@ export const mountStaticAidMaps = root => {
 }
 
 export const Hooks = {
+  CopyToClipboard: {
+    mounted() {
+      this.resetLabel = () => {
+        this.el.textContent = this.el.dataset.defaultLabel
+      }
+
+      this.copy = async () => {
+        const value = this.el.dataset.copyValue || ""
+
+        const fallbackCopy = () => {
+          const input = document.createElement("textarea")
+          input.value = value
+          input.setAttribute("readonly", "")
+          input.style.position = "fixed"
+          input.style.opacity = "0"
+          document.body.append(input)
+          input.select()
+          const copied = document.execCommand("copy")
+          input.remove()
+
+          if (!copied) throw new Error("Clipboard copy failed")
+        }
+
+        try {
+          if (navigator.clipboard?.writeText) {
+            await navigator.clipboard.writeText(value)
+          } else {
+            fallbackCopy()
+          }
+          this.el.textContent = this.el.dataset.copiedLabel
+        } catch (_error) {
+          try {
+            fallbackCopy()
+            this.el.textContent = this.el.dataset.copiedLabel
+          } catch (_fallbackError) {
+            this.el.textContent = this.el.dataset.errorLabel
+          }
+        }
+
+        window.clearTimeout(this.labelTimer)
+        this.labelTimer = window.setTimeout(this.resetLabel, 1800)
+      }
+
+      this.el.addEventListener("click", this.copy)
+    },
+    destroyed() {
+      this.el.removeEventListener("click", this.copy)
+      window.clearTimeout(this.labelTimer)
+    }
+  },
+
+  HandoverCode: {
+    mounted() {
+      this.normalize = () => {
+        this.el.value = this.el.value.replace(/[^0-9]/g, "").slice(0, 6)
+      }
+
+      this.el.addEventListener("input", this.normalize)
+    },
+    destroyed() {
+      this.el.removeEventListener("input", this.normalize)
+    }
+  },
+
   AidMap: {
     mounted() {
       this.aidMap = createAidMap(this.el)

lib/who_need_help/help.ex

@@ -290,6 +290,8 @@ defmodule WhoNeedHelp.Help do
   end
 
   def verify_handover(%Scope{user: user}, assignment_id, code) do
+    code = normalize_handover_code(code)
+
     with {:ok, assignment_id} <- cast_id(assignment_id),
          true <- valid_handover_code?(code),
          {:ok, _limit} <- Trust.authorize_action(Scope.for_user(user), :verify_handover) do
@@ -619,6 +621,14 @@ defmodule WhoNeedHelp.Help do
 
   defp valid_handover_code?(_code), do: false
 
+  defp normalize_handover_code(code) when is_binary(code) do
+    code
+    |> String.slice(0, 64)
+    |> String.replace(~r/[^0-9]/u, "")
+  end
+
+  defp normalize_handover_code(code), do: code
+
   defp code_hash(code) when is_binary(code), do: :crypto.hash(:sha256, code)
 
   defp after_transition({:ok, assignment}) do

lib/who_need_help_web/live/request_live/show.ex

@@ -1010,9 +1010,22 @@ defmodule WhoNeedHelpWeb.RequestLive.Show do
                     <div class="text-xs opacity-65">
                       {gettext("HANDOVER CODE FOR THE HELPER")}
                     </div>
-                    <div class="mt-1 font-mono text-3xl font-black tracking-[.25em]">
+                    <code class="mt-1 block select-all font-mono text-3xl font-black tracking-normal">
                       {Help.handover_code(@request.id)}
-                    </div>
+                    </code>
+                    <button
+                      id="copy-handover-code"
+                      type="button"
+                      phx-hook="CopyToClipboard"
+                      data-copy-value={Help.handover_code(@request.id)}
+                      data-default-label={gettext("Copy code")}
+                      data-copied-label={gettext("Copied")}
+                      data-error-label={gettext("Copy failed")}
+                      class="btn btn-sm btn-outline mt-3"
+                      aria-live="polite"
+                    >
+                      {gettext("Copy code")}
+                    </button>
                   </div>
 
                   <.form
@@ -1028,11 +1041,10 @@ defmodule WhoNeedHelpWeb.RequestLive.Show do
                       field={@handover_form[:code]}
                       label={gettext("Enter handover code")}
                       type="text"
+                      phx-hook="HandoverCode"
                       inputmode="numeric"
                       autocomplete="one-time-code"
-                      minlength="6"
-                      maxlength="6"
-                      pattern="[0-9]{6}"
+                      maxlength="32"
                       placeholder="000000"
                       required
                       aria-describedby="handover-code-hint"

test/who_need_help/mutual_aid_flow_test.exs

@@ -100,6 +100,14 @@ defmodule WhoNeedHelp.MutualAidFlowTest do
       assert {:error, :invalid_code} =
                Help.verify_handover(context.helper_scope, assignment.id, code)
     end
+
+    code = Help.handover_code(request.id)
+    pasted_code = String.slice(code, 0, 3) <> " " <> String.slice(code, 3, 3)
+
+    assert {:ok, verified_assignment} =
+             Help.verify_handover(context.helper_scope, assignment.id, pasted_code)
+
+    assert verified_assignment.handover_verified_at
   end
 
   test "request location labels are validated before the database write", context do

test/who_need_help_web/live/mutual_aid_live_test.exs

@@ -660,13 +660,13 @@ defmodule WhoNeedHelpWeb.MutualAidLiveTest do
     {:ok, view, _html} =
       build_conn() |> log_in_user(helper) |> live(~p"/requests/#{request.id}")
 
-    assert has_element?(
-             view,
-             "#handover-form input[inputmode='numeric'][autocomplete='one-time-code'][pattern='[0-9]{6}']"
-           )
+    assert has_element?(view, "#handover-form input[phx-hook='HandoverCode'][maxlength='32']")
+
+    code = Help.handover_code(request.id)
+    pasted_code = String.slice(code, 0, 3) <> " " <> String.slice(code, 3, 3)
 
     view
-    |> form("#handover-form", handover: %{code: Help.handover_code(request.id)})
+    |> form("#handover-form", handover: %{code: pasted_code})
     |> render_submit()
 
     assert render(view) =~ "Handover code verified."