flotilla/src/app/components/WalletPay.svelte

<script lang="ts">
  import {Invoice} from "@getalby/lightning-tools/bolt11"
  import {debounce} from "throttle-debounce"
  import {session} from "@welshman/app"
  import Bolt from "@assets/icons/bolt.svg?dataurl"
  import AltArrowLeft from "@assets/icons/alt-arrow-left.svg?dataurl"
  import Icon from "@lib/components/Icon.svelte"
  import Button from "@lib/components/Button.svelte"
  import FieldInline from "@lib/components/FieldInline.svelte"
  import Scanner from "@lib/components/Scanner.svelte"
  import Modal from "@lib/components/Modal.svelte"
  import ModalBody from "@lib/components/ModalBody.svelte"
  import ModalHeader from "@lib/components/ModalHeader.svelte"
  import ModalTitle from "@lib/components/ModalTitle.svelte"
  import ModalSubtitle from "@lib/components/ModalSubtitle.svelte"
  import ModalFooter from "@lib/components/ModalFooter.svelte"
  import {errorMessage} from "@lib/util"
  import {payInvoice} from "@app/core/commands"
  import {pushToast} from "@app/util/toast"
  import {clearModals} from "@app/util/modal"

  const back = () => history.back()

  const onScan = debounce(1000, async (data: string) => {
    invoice = new Invoice({pr: data})
    sats = invoice.satoshi || 0
  })

  const confirm = async () => {
    loading = true

    try {
      if (hasAmount) {
        await payInvoice(invoice!.paymentRequest)
      } else {
        await payInvoice(invoice!.paymentRequest, sats * 1000)
      }

      pushToast({message: `Payment sent!`})
      clearModals()
    } catch (e) {
      console.error(e)

      const message = errorMessage(e)

      pushToast({
        theme: "error",
        message: `Failed to send payment: ${message}`,
      })
    } finally {
      loading = false
    }
  }

  let loading = $state(false)
  let invoice: Invoice | undefined = $state()
  let sats = $state(0)
  const hasAmount = $derived((invoice?.satoshi ?? 0) > 0)
</script>

<Modal>
  <ModalBody>
    <ModalHeader>
      <ModalTitle>Pay with Lightning</ModalTitle>
      <ModalSubtitle>Use your Nostr wallet to send Bitcoin payments over lightning.</ModalSubtitle>
    </ModalHeader>
    {#if invoice}
      <div class="card2 bg-alt flex flex-col gap-2">
        {#if $session?.wallet?.type === "webln" && !hasAmount}
          <p class="text-sm opacity-75">
            Uh oh! It looks like your current wallet doesn't support invoices without an amount. See
            if you can get a lightning invoice with a pre-set amount.
          </p>
        {:else}
          <FieldInline>
            {#snippet label()}
              Amount (satoshis)
            {/snippet}
            {#snippet input()}
              <div class="flex flex-grow justify-end">
                <label class="input input-bordered flex items-center gap-2">
                  <Icon icon={Bolt} />
                  <input
                    bind:value={sats}
                    type="number"
                    class="w-14"
                    disabled={invoice!.satoshi > 0} />
                </label>
              </div>
            {/snippet}
          </FieldInline>
          <p class="text-sm opacity-75">
            You're about to pay a bitcoin lightning invoice with the following description:
            <strong>{invoice.description || "[no description]"}</strong>"
          </p>
        {/if}
      </div>
    {:else}
      <Scanner onscan={onScan} />
      <p class="text-center text-sm opacity-75">
        To make a payment, scan a lightning invoice with your camera.
      </p>
    {/if}
  </ModalBody>
  <ModalFooter>
    <Button class="btn btn-link" onclick={back}>
      <Icon icon={AltArrowLeft} />
      Go back
    </Button>
    <Button
      class="btn btn-primary"
      onclick={confirm}
      disabled={!invoice ||
        sats === 0 ||
        loading ||
        ($session?.wallet?.type === "webln" && !hasAmount)}>
      {#if loading}
        <span class="loading loading-spinner loading-sm"></span>
      {:else}
        <Icon icon={Bolt} />
      {/if}
      Confirm Payment
    </Button>
  </ModalFooter>
</Modal>