flotilla/src/routes/spaces/[relay]/[h]/+page.svelte

<script lang="ts">
  import {onMount} from "svelte"
  import {readable} from "svelte/store"
  import {page} from "$app/stores"
  import {goto} from "$app/navigation"
  import type {Readable} from "svelte/store"
  import {pubkey, publishThunk, waitForThunkError, joinRoom, leaveRoom} from "@welshman/app"
  import {now, ifLet, int, formatTimestampAsDate, ago, MINUTE} from "@welshman/lib"
  import type {MakeNonOptional} from "@welshman/lib"
  import type {TrustedEvent, EventContent} from "@welshman/util"
  import {makeEvent, makeRoomMeta, MESSAGE, ROOM_ADD_MEMBER} from "@welshman/util"
  import AltArrowDown from "@assets/icons/alt-arrow-down.svg?dataurl"
  import ClockCircle from "@assets/icons/clock-circle.svg?dataurl"
  import InfoCircle from "@assets/icons/info-circle.svg?dataurl"
  import Login2 from "@assets/icons/login-3.svg?dataurl"
  import cx from "classnames"
  import {slide, fade, fly} from "@lib/transition"
  import Button from "@lib/components/Button.svelte"
  import Divider from "@lib/components/Divider.svelte"
  import Icon from "@lib/components/Icon.svelte"
  import PageContent from "@lib/components/PageContent.svelte"
  import Spinner from "@lib/components/Spinner.svelte"
  import SpaceBar from "@app/components/SpaceBar.svelte"
  import RoomCompose from "@app/components/RoomCompose.svelte"
  import RoomComposeParent from "@app/components/RoomComposeParent.svelte"
  import RoomImage from "@app/components/RoomImage.svelte"
  import RoomDetail from "@app/components/RoomDetail.svelte"
  import RoomItem from "@app/components/RoomItem.svelte"
  import RoomName from "@app/components/RoomName.svelte"
  import SpaceSearch from "@app/components/SpaceSearch.svelte"
  import ThunkToast from "@app/components/ThunkToast.svelte"
  import RoomItemAddMember from "@src/app/components/RoomItemAddMember.svelte"
  import RoomComposeEdit from "@src/app/components/RoomComposeEdit.svelte"
  import {canEnforceNip70, prependParent, publishDelete} from "@app/core/commands"
  import {
    decodeRelay,
    deriveRoom,
    deriveUserRoomMembershipStatus,
    getRoomType,
    MESSAGE_KINDS,
    MembershipStatus,
    PROTECTED,
    RoomType,
    userSettingsValues,
  } from "@app/core/state"
  import VoiceWidget from "@app/components/VoiceWidget.svelte"
  import VideoCallContent from "@app/components/VideoCallContent.svelte"
  import {VoiceState, currentVoiceRoom, voiceState} from "@app/call/stores"
  import {VideoCallLayout, videoCallLayout, videoTileCount} from "@app/call/video"
  import {makeFeed} from "@app/core/requests"
  import {popKey} from "@lib/implicit"
  import {checked} from "@app/util/notifications"
  import {pushModal} from "@app/util/modal"
  import {pushToast} from "@app/util/toast"

  const {h, relay} = $page.params as MakeNonOptional<typeof $page.params>
  const mounted = now()
  const lastChecked = $checked[$page.url.pathname]
  const url = decodeRelay(relay)
  const room = deriveRoom(url, h)
  const isVoiceRoom = $derived(getRoomType($room) === RoomType.Voice)

  const voiceConnectedHere = $derived(
    isVoiceRoom &&
      $voiceState === VoiceState.Connected &&
      $currentVoiceRoom?.url === url &&
      $currentVoiceRoom?.h === h,
  )

  const showMobileVideoPanel = $derived(
    isVoiceRoom &&
      $voiceState === VoiceState.Connected &&
      $videoCallLayout === VideoCallLayout.Video,
  )

  const pageContentHiddenDesktopVideoOnly = $derived(
    voiceConnectedHere && $videoCallLayout === VideoCallLayout.Video,
  )

  let prevVideoTileCount = $state(0)

  $effect(() => {
    if ($voiceState !== VoiceState.Connected) {
      videoCallLayout.set(VideoCallLayout.Chat)
      prevVideoTileCount = 0
      return
    }

    const here = isVoiceRoom && $currentVoiceRoom?.url === url && $currentVoiceRoom?.h === h
    const n = $videoTileCount

    if (!here) {
      prevVideoTileCount = 0
      return
    }

    if (prevVideoTileCount === 0 && n >= 1) {
      videoCallLayout.set(VideoCallLayout.Video)
    }
    if (prevVideoTileCount >= 1 && n === 0 && $videoCallLayout === VideoCallLayout.Split) {
      videoCallLayout.set(VideoCallLayout.Chat)
    }
    prevVideoTileCount = n
  })
  const shouldProtect = canEnforceNip70(url)
  const membershipStatus = deriveUserRoomMembershipStatus(url, h)
  const at = $derived(parseInt($page.url.searchParams.get("at")!))

  const showRoomDetail = () => pushModal(RoomDetail, {url, h})

  const join = async () => {
    joining = true

    try {
      const message = await waitForThunkError(joinRoom(url, makeRoomMeta({h})))

      if (message && !message.startsWith("duplicate:")) {
        return pushToast({theme: "error", message})
      }

      // Restart the feed now that we're a member
      start()
    } finally {
      joining = false
    }
  }

  const leave = async () => {
    leaving = true
    try {
      const message = await waitForThunkError(leaveRoom(url, makeRoomMeta({h})))

      if (message && !message.startsWith("duplicate:")) {
        pushToast({theme: "error", message})
      }
    } finally {
      leaving = false
    }
  }

  const replyTo = (event: TrustedEvent) => {
    parent = event
    compose?.focus()
  }

  const clearParent = () => {
    parent = undefined
  }

  const clearShare = () => {
    share = undefined
  }

  const clearEventToEdit = () => {
    eventToEdit = undefined
  }

  const onSubmit = async ({content, tags}: EventContent) => {
    try {
      tags.push(["h", h])

      if (await shouldProtect) {
        tags.push(PROTECTED)
      }

      let template: EventContent & {created_at?: number} = {content, tags}

      if (eventToEdit) {
        // Don't do anything if message hasn't changed
        if (eventToEdit.content === content) {
          return
        }

        // Delete previous message, to be republished with same timestamp
        template.created_at = eventToEdit.created_at
        publishDelete({
          relays: [url],
          event: $state.snapshot(eventToEdit),
          protect: await shouldProtect,
        })
      }

      if (share) {
        template = prependParent(share, template, url)
      }

      if (parent) {
        template = prependParent(parent, template, url)
      }

      const thunk = publishThunk({
        relays: [url],
        event: makeEvent(MESSAGE, template),
        delay: $userSettingsValues.send_delay,
      })

      if ($userSettingsValues.send_delay) {
        pushToast({
          timeout: 30_000,
          children: {
            component: ThunkToast,
            props: {thunk},
          },
        })
      }
    } finally {
      clearParent()
      clearShare()
      clearEventToEdit()
    }
  }

  const manageScrollPosition = () => {
    showScrollButton = !isNaN(at) || Math.abs(element?.scrollTop || 0) > 1500

    const newMessages = document.getElementById("new-messages")

    if (newMessagesSeen) {
      showFixedNewMessages = false
    } else if (newMessages) {
      const {y} = newMessages.getBoundingClientRect()

      if (y > 0 && y < 300) {
        newMessagesSeen = true
        showFixedNewMessages = false
      } else {
        showFixedNewMessages = y < 0
      }
    }

    if (!userHasScrolled && !isNaN(at)) {
      const targetEvent = $events.find(event => event.created_at >= at)

      if (targetEvent) {
        const target = element?.querySelector(`[data-event="${targetEvent.id}"]`)

        if (target instanceof HTMLElement) {
          isProgrammaticScroll = true
          target.scrollIntoView({block: "center"})
        }
      }
    }
  }

  const onScroll = () => {
    if (!isProgrammaticScroll) {
      userHasScrolled = true
      manageScrollPosition()
    }

    isProgrammaticScroll = false
  }

  const scrollToNewMessages = () =>
    document.getElementById("new-messages")?.scrollIntoView({behavior: "smooth", block: "center"})

  const scrollToBottom = () => {
    if (!isNaN(at)) {
      goto($page.url.pathname, {replaceState: true})
    } else {
      element?.scrollTo({top: 0, behavior: "smooth"})
    }
  }

  let joining = $state(false)
  let leaving = $state(false)
  let userHasScrolled = $state(false)
  let isProgrammaticScroll = $state(false)
  let loadingBackward = $state(true)
  let loadingForward = $state(true)
  let share = $state(popKey<TrustedEvent | undefined>("share"))
  let parent: TrustedEvent | undefined = $state()
  let element: HTMLElement | undefined = $state()
  let newMessagesSeen = false
  let showFixedNewMessages = $state(false)
  let showScrollButton = $state(false)
  let cleanup: () => void
  let events: Readable<TrustedEvent[]> = $state(readable([]))
  let compose: RoomCompose | undefined = $state()
  let eventToEdit: TrustedEvent | undefined = $state()

  const elements = $derived.by(() => {
    const elements = []
    const seen = new Set()

    let previousDate
    let previousKind
    let previousPubkey
    let previousCreatedAt = 0
    let newMessagesSeen = false

    if (events) {
      const lastUserEvent = $events.find(e => e.pubkey === $pubkey)

      // Adjust last checked to account for messages that came from a different device
      const adjustedLastChecked =
        lastChecked && lastUserEvent ? Math.max(lastUserEvent.created_at, lastChecked) : lastChecked

      for (const event of $events) {
        if (seen.has(event.id)) {
          continue
        }

        const date = formatTimestampAsDate(event.created_at)

        if (
          !newMessagesSeen &&
          adjustedLastChecked &&
          event.pubkey !== $pubkey &&
          event.created_at > adjustedLastChecked &&
          event.created_at < mounted
        ) {
          elements.push({type: "new-messages", id: "new-messages"})
          newMessagesSeen = true
        }

        if (date !== previousDate) {
          elements.push({type: "date", value: date, id: date, showPubkey: false})
        }

        const showPubkey =
          previousPubkey !== event.pubkey ||
          event.created_at - previousCreatedAt > int(3, MINUTE) ||
          previousKind === ROOM_ADD_MEMBER

        if (showPubkey && elements.length > 0) {
          elements[elements.length - 1].addSpaceBelow = true
        }

        elements.push({
          id: event.id,
          type: "note",
          value: event,
          showPubkey,
          addSpaceBelow: false,
        })

        previousDate = date
        previousKind = event.kind
        previousPubkey = event.pubkey
        previousCreatedAt = event.created_at
        seen.add(event.id)
      }
      if (elements.length > 0) {
        elements[elements.length - 1].addSpaceBelow = true
      }
    }

    elements.reverse()

    requestAnimationFrame(manageScrollPosition)

    return elements
  })

  const start = () => {
    cleanup?.()

    const feed = makeFeed({
      url,
      at: at || now(),
      element: element!,
      filters: [{kinds: [...MESSAGE_KINDS, ROOM_ADD_MEMBER], "#h": [h]}],
      onBackwardExhausted: () => {
        loadingBackward = false
      },
      onForwardExhausted: () => {
        loadingForward = false
      },
    })

    events = feed.events
    cleanup = feed.cleanup
  }

  const onEscape = () => {
    clearParent()
    clearShare()
    eventToEdit = undefined
  }

  const canEditEvent = (event: TrustedEvent) =>
    event.pubkey === $pubkey && event.created_at >= ago(5, MINUTE)

  const onEditEvent = (event: TrustedEvent) => {
    clearParent()
    clearShare()
    eventToEdit = event
  }

  const onEditPrevious = () => ifLet($events.toReversed().find(canEditEvent), onEditEvent)

  onMount(() => {
    start()

    return cleanup
  })
</script>

<SpaceBar>
  {#snippet title()}
    <RoomImage {url} {h} />
    <RoomName {url} {h} />
  {/snippet}
  {#snippet action()}
    <SpaceSearch {url} {h} />
    <Button class="btn btn-neutral btn-sm btn-square" onclick={showRoomDetail}>
      <Icon size={4} icon={InfoCircle} />
    </Button>
  {/snippet}
</SpaceBar>

<div
  class={cx(
    "flex min-h-0 flex-1 flex-col",
    voiceConnectedHere && $videoCallLayout === VideoCallLayout.Split && "md:flex-row",
  )}>
  {#if voiceConnectedHere}
    <VideoCallContent
      layout={$videoCallLayout}
      {url}
      {h}
      class="hidden min-h-0 w-full min-w-0 flex-1 flex-col md:flex" />
  {/if}

  <div
    class={cx(
      "flex min-h-0 min-w-0 flex-1 flex-col",
      voiceConnectedHere && $videoCallLayout === VideoCallLayout.Video && "md:hidden",
    )}>
    {#if isVoiceRoom && $voiceState === VoiceState.Connected}
      <VideoCallContent layout={$videoCallLayout} mobile {url} {h} class="md:hidden" />
    {/if}

    <PageContent
      bind:element
      onscroll={onScroll}
      class={cx(
        showMobileVideoPanel
          ? "hidden flex-col-reverse pt-4 md:flex md:flex-col-reverse"
          : "flex flex-col-reverse pt-4",
        pageContentHiddenDesktopVideoOnly && "md:hidden",
      )}>
      {#if $room.isPrivate && $membershipStatus !== MembershipStatus.Granted}
        <div class="py-20">
          <div class="card2 col-8 m-auto max-w-md items-center text-center">
            <p class="opacity-75">You aren't currently a member of this room.</p>
            {#if $membershipStatus === MembershipStatus.Pending}
              <Button class="btn btn-neutral btn-sm" disabled={leaving} onclick={leave}>
                <Icon icon={ClockCircle} />
                Access Pending
              </Button>
            {:else}
              <Button class="btn btn-neutral btn-sm" disabled={joining} onclick={join}>
                {#if joining}
                  <span class="loading loading-spinner loading-sm"></span>
                {:else}
                  <Icon icon={Login2} />
                {/if}
                Join Room
              </Button>
            {/if}
          </div>
        </div>
      {:else}
        {#if loadingForward}
          <p class="py-20 flex justify-center">
            <Spinner loading={loadingForward}>Looking for messages...</Spinner>
          </p>
        {/if}
        {#each elements as { type, id, value, showPubkey, addSpaceBelow } (id)}
          {#if type === "new-messages"}
            <div
              {id}
              class="flex items-center py-2 text-xs transition-colors"
              class:opacity-0={showFixedNewMessages}>
              <div class="h-px flex-grow bg-primary"></div>
              <p class="rounded-full bg-primary px-2 py-1 text-primary-content">New Messages</p>
              <div class="h-px flex-grow bg-primary"></div>
            </div>
          {:else if type === "date"}
            <Divider>{value}</Divider>
          {:else}
            {@const event = $state.snapshot(value as TrustedEvent)}
            {#if event.kind === ROOM_ADD_MEMBER}
              <RoomItemAddMember {url} {event} />
            {:else}
              <div in:slide class="cv">
                <RoomItem
                  {url}
                  {event}
                  {replyTo}
                  {showPubkey}
                  {addSpaceBelow}
                  canEdit={canEditEvent}
                  onEdit={onEditEvent} />
              </div>
            {/if}
          {/if}
        {/each}
        <p class="flex h-10 items-center justify-center py-20">
          {#if loadingBackward}
            <Spinner loading={loadingBackward}>Looking for messages...</Spinner>
          {:else}
            <Spinner>End of message history</Spinner>
          {/if}
        </p>
      {/if}
      <div class="h-screen"></div>
    </PageContent>

    <div
      class={cx(
        "chat__compose-zone chat__compose flex flex-col gap-1 bg-base-200 md:flex-row md:gap-0",
        pageContentHiddenDesktopVideoOnly && "md:hidden",
        showMobileVideoPanel && "max-md:hidden",
      )}>
      <div class="chat__compose-inner min-w-0 flex-1">
        {#if $room.isPrivate && $membershipStatus !== MembershipStatus.Granted}
          <!-- pass -->
        {:else if $room.isRestricted && $membershipStatus !== MembershipStatus.Granted}
          <div class="bg-alt card m-4 flex flex-row items-center justify-between px-4 py-3">
            <p class="opacity-75">Only members are allowed to post to this room.</p>
            {#if $membershipStatus === MembershipStatus.Pending}
              <Button class="btn btn-neutral btn-sm" disabled={leaving} onclick={leave}>
                <Icon icon={ClockCircle} />
                Access Pending
              </Button>
            {:else}
              <Button class="btn btn-neutral btn-sm" disabled={joining} onclick={join}>
                {#if joining}
                  <span class="loading loading-spinner loading-sm"></span>
                {:else}
                  <Icon icon={Login2} />
                {/if}
                Ask to Join
              </Button>
            {/if}
          </div>
        {:else}
          <div>
            {#if parent}
              <RoomComposeParent event={parent} clear={clearParent} verb="Replying to" />
            {/if}
            {#if share}
              <RoomComposeParent event={share} clear={clearShare} verb="Sharing" />
            {/if}
            {#if eventToEdit}
              <RoomComposeEdit clear={clearEventToEdit} />
            {/if}
          </div>
          {#key eventToEdit}
            <RoomCompose
              {url}
              {h}
              {onSubmit}
              {onEscape}
              {onEditPrevious}
              initialValues={eventToEdit}
              bind:this={compose} />
          {/key}
        {/if}
      </div>
      {#if isVoiceRoom || $voiceState === VoiceState.Joining || $voiceState === VoiceState.Connected}
        <div
          class={cx(
            "hide-on-keyboard flex-shrink-0 p-2 md:hidden",
            showMobileVideoPanel && "hidden",
          )}>
          <VoiceWidget />
        </div>
      {/if}
    </div>
  </div>
</div>

{#if showScrollButton}
  <div in:fade class="chat__scroll-down">
    <Button class="btn btn-circle btn-neutral" onclick={scrollToBottom}>
      <Icon icon={AltArrowDown} />
    </Button>
  </div>
{/if}

{#if showFixedNewMessages}
  <div class="relative z-popover flex justify-center">
    <div transition:fly={{duration: 200}} class="fixed top-12 pt-sai">
      <Button class="btn btn-primary btn-xs rounded-full" onclick={scrollToNewMessages}>
        New Messages
      </Button>
    </div>
  </div>
{/if}