Workflows

import { AppShell } from "@/components/ui/app-shell"
import { PageHeader } from "@/components/ui/page-header"

import { signOut } from "./actions"
import { WorkflowsView } from "./components/workflows-view"
import { NODE_ICONS, currentUser, now, runSummary, shellNotifications, workflowRows } from "./data"
import { NAV, ROUTES } from "@/lib/dashboards/projects/nav"

/**
 * The automations. The page is a server component: it reads every workflow
 * through `db.workflows`, draws each step's icon here from the fixed map a
 * step's icon name points into, and hands one client island the graphs and
 * their runs. The island draws the canvas and changes things only through
 * the page's actions.
 */
export default function WorkflowsPage() {
  const workflows = workflowRows().map((workflow) => ({
    ...workflow,
    nodes: workflow.nodes.map((node) => {
      const Icon = NODE_ICONS[node.icon]
      return { ...node, glyph: <Icon aria-hidden="true" /> }
    }),
  }))

  return (
    <AppShell
      nav={NAV}
      activeHref={ROUTES.workflows}
      user={currentUser()}
      notifications={shellNotifications()}
      now={now()}
      onSignOut={signOut}
    >
      <PageHeader
        title="Workflows"
        description="Automations that move orders, payments and leads between Northwind's tools."
        meta={runSummary()}
      />

      <WorkflowsView workflows={workflows} now={now()} />
    </AppShell>
  )
}

/**
 * What the workflows page reads: every automation in `db.workflows`, its
 * graph and its runs. A step names its icon as a lucide name; NODE_ICONS below
 * is the fixed map from that name to the component that draws it, and the
 * page draws each step's icon on the server with it. "Now" is REFERENCE_DATE.
 */
import {
  Building2Icon,
  CalendarClockIcon,
  ChartLineIcon,
  ClipboardListIcon,
  CreditCardIcon,
  FileTextIcon,
  FlagIcon,
  GaugeIcon,
  HourglassIcon,
  ListTodoIcon,
  MailIcon,
  MessageCircleIcon,
  MessageSquareIcon,
  PackageIcon,
  ReceiptIcon,
  RotateCwIcon,
  ShoppingCartIcon,
  SplitIcon,
  TagIcon,
  TicketIcon,
  UserCheckIcon,
  UserPlusIcon,
  UsersIcon,
  type LucideIcon,
} from "lucide-react"

import { getInitials } from "@/lib/format"
import { REFERENCE_DATE, daysAgo, db, type Member, type Workflow, type WorkflowIcon } from "@/lib/sample-data"

/** Every icon a step may name, drawn: the entity's WORKFLOW_ICONS, one component each. */
export const NODE_ICONS: Record<WorkflowIcon, LucideIcon> = {
  "building-2": Building2Icon,
  "calendar-clock": CalendarClockIcon,
  "chart-line": ChartLineIcon,
  "clipboard-list": ClipboardListIcon,
  "credit-card": CreditCardIcon,
  "file-text": FileTextIcon,
  flag: FlagIcon,
  gauge: GaugeIcon,
  hourglass: HourglassIcon,
  "list-todo": ListTodoIcon,
  mail: MailIcon,
  "message-circle": MessageCircleIcon,
  "message-square": MessageSquareIcon,
  package: PackageIcon,
  receipt: ReceiptIcon,
  "rotate-cw": RotateCwIcon,
  "shopping-cart": ShoppingCartIcon,
  split: SplitIcon,
  tag: TagIcon,
  ticket: TicketIcon,
  "user-check": UserCheckIcon,
  "user-plus": UserPlusIcon,
  users: UsersIcon,
}

/** Every workflow, in the order the book keeps them: the live ones, the paused one, the drafts. */
export function workflowRows(): Workflow[] {
  return db.workflows.all()
}

/** How far back the run history reaches. */
const WINDOW_DAYS = 14

/** "41 runs in the last 14 days, 4 of them failed": the whole book in a line, for the header. */
export function runSummary(): string {
  const since = daysAgo(WINDOW_DAYS).getTime()
  const runs = db.workflows.all().flatMap((row) => row.runs.filter((run) => run.startedAt.getTime() >= since))
  const failed = runs.filter((run) => run.status === "failed").length
  return `${runs.length} runs in the last ${WINDOW_DAYS} days${failed ? `, ${failed} of them failed` : ""}`
}

/** The bell's contents: the newest notifications, unread first in the panel. */
export function shellNotifications() {
  return db.notifications
    .all()
    .sort((a, b) => b.at.getTime() - a.at.getTime())
    .slice(0, 6)
    .map(({ id, title, description, at, read, href }) => ({ id, title, description, at, read, href }))
}

function ownerRow(): Member {
  return db.members.all().find((member) => member.role === "owner") ?? db.members.all()[0]
}

/** The person looking at the page: whoever owns this workspace. */
export function currentUser() {
  const owner = ownerRow()
  return { name: owner.name, email: owner.email, initials: getInitials(owner.name), avatarUrl: owner.avatarUrl }
}

/** "Now", for the island's relative times — the reference instant, never the clock. */
export function now(): Date {
  return REFERENCE_DATE
}

"use server"

import { mockAuthAdapter } from "@/lib/auth-adapter"
import { REFERENCE_DATE, asString, db, type Result, type Workflow, type WorkflowRun } from "@/lib/sample-data"

import { RUN_MS, runnable } from "./flow"

/**
 * What the workflows page changes. Server actions, so the page stays a server
 * component; `Result`, so a refusal comes back as a sentence the page shows
 * beside the control that asked. Every action looks the workflow up again and
 * trusts the stored row, never what the canvas says it was.
 */

export async function signOut(): Promise<Result<{ signedOut: true }>> {
  await mockAuthAdapter.signOut()
  return { ok: true, data: { signedOut: true } }
}

/** The longest name a step's box can show on one line. */
const MAX_TITLE = 48

/** How many runs a workflow's history keeps: the newest hundred. */
const MAX_RUNS = 100

const refuse = (code: string, message: string, field?: string): Result<never> => ({
  ok: false,
  error: field ? { code, message, field } : { code, message },
})

const noWorkflow = (id: string) => refuse("not_found", `No workflow with id "${id}".`)

/** Renames one step. Refuses an empty name, one too long for its box, and a step or workflow that is not there. */
export async function renameStep(
  workflowId: string,
  nodeId: string,
  title: string
): Promise<Result<{ workflowId: string; nodeId: string; title: string }>> {
  const workflow = await db.workflows.get(workflowId)
  if (!workflow) return noWorkflow(workflowId)
  const step = workflow.nodes.find((node) => node.id === nodeId)
  if (!step) return refuse("not_found", `${workflow.name} has no step "${nodeId}".`)

  const name = asString(title).trim().replace(/\s+/g, " ")
  if (!name) return refuse("empty", "A step needs a name.", "title")
  if (name.length > MAX_TITLE) return refuse("too_long", `A step's name fits in ${MAX_TITLE} characters.`, "title")

  const updated = await db.workflows.update(workflow.id, {
    nodes: workflow.nodes.map((node) => (node.id === step.id ? { ...node, title: name } : node)),
  })
  if (!updated.ok) return updated
  return { ok: true, data: { workflowId: workflow.id, nodeId: step.id, title: name } }
}

/**
 * Switches a workflow on or off. Switching on refuses a workflow that cannot
 * run — no trigger to start it, or nothing for it to do — which is how a
 * half-built draft stays a draft; switching off refuses a draft, which was
 * never on.
 */
export async function setWorkflowStatus(
  id: string,
  status: "active" | "paused"
): Promise<Result<{ id: string; status: Workflow["status"] }>> {
  const workflow = await db.workflows.get(id)
  if (!workflow) return noWorkflow(id)
  if (status !== "active" && status !== "paused") return refuse("invalid", "A workflow is switched on or off, nothing else.")

  if (status === "active" && !runnable(workflow)) {
    return refuse(
      "incomplete",
      `${workflow.name} needs a trigger and at least one action before it can be switched on.`,
      "status"
    )
  }
  if (status === "paused" && workflow.status === "draft") {
    return refuse("invalid", `${workflow.name} is a draft — it has never been on, so there is nothing to pause.`, "status")
  }
  if (workflow.status === status) return { ok: true, data: { id: workflow.id, status } }

  const updated = await db.workflows.update(workflow.id, { status })
  if (!updated.ok) return updated
  return { ok: true, data: { id: workflow.id, status: updated.data.status } }
}

/** The next run number after every run in the book. */
function nextRunId(): string {
  const highest = db.workflows
    .all()
    .flatMap((row) => row.runs)
    .reduce((max, run) => Math.max(max, Number(run.id.replace(/\D/g, "")) || 0), 0)
  return `run_${String(highest + 1).padStart(5, "0")}`
}

/**
 * Runs a workflow now and records how it went: every step went through, in
 * the time a run takes. The book has the outcome from the start, so a page
 * closed mid-run never leaves one running; the page alone plays the run out
 * for that long. Refuses a workflow that cannot run.
 */
export async function runWorkflow(id: string): Promise<Result<{ workflowId: string; run: WorkflowRun }>> {
  const workflow = await db.workflows.get(id)
  if (!workflow) return noWorkflow(id)
  if (!runnable(workflow)) {
    return refuse("incomplete", `${workflow.name} needs a trigger and at least one action before it can run.`, "run")
  }

  const run: WorkflowRun = { id: nextRunId(), startedAt: REFERENCE_DATE, durationMs: RUN_MS, status: "succeeded" }
  // The history keeps the newest runs, not every click: a row in a store every
  // visitor shares cannot grow by one for each press of Run.
  const updated = await db.workflows.update(workflow.id, { runs: [...workflow.runs, run].slice(-MAX_RUNS) })
  if (!updated.ok) return updated
  return { ok: true, data: { workflowId: workflow.id, run } }
}

/**
 * The canvas's geometry and the one rule a workflow is held to, in plain
 * functions: where an edge runs, how big the graph is, what view fits it,
 * what a step sits between, and whether a workflow can run at all. The island
 * draws with the geometry; the actions hold a workflow to `runnable`, and the
 * switch shows what they answer.
 */
import type * as React from "react"

import type { Workflow, WorkflowNode, WorkflowRun } from "@/lib/sample-data"

/** A step's box on the plane, in pixels at 100%: the grid the entity lays steps on leaves room for this. */
export const NODE_WIDTH = 216
export const NODE_HEIGHT = 76

/**
 * The zoom's range, and one press of − or +. The floor is low enough that Fit
 * shows the longest seeded graph whole in a phone's 358px canvas (23%); the
 * steps are then a map of the flow, not something to read.
 */
export const ZOOM_MIN = 0.2
export const ZOOM_MAX = 1.5
export const ZOOM_STEP = 0.1

/** How far one arrow key moves the plane, and how far with Shift held. */
export const PAN_STEP = 48
export const PAN_STEP_LARGE = 192

/** How long a run started from the page takes — and so how long the history shows it running. */
export const RUN_MS = 1200

export const KIND_LABELS: Record<WorkflowNode["kind"], string> = {
  trigger: "Trigger",
  action: "Action",
  branch: "Branch",
  delay: "Delay",
}

export const STATUS_LABELS: Record<Workflow["status"], string> = { active: "Active", paused: "Paused", draft: "Draft" }

export const RUN_LABELS: Record<WorkflowRun["status"], string> = {
  succeeded: "Succeeded",
  failed: "Failed",
  running: "Running",
}

/**
 * What a step sits between: the titles of the steps that lead into it, and
 * each way out of it with the branch's answer, if it has one. The step's
 * description on the canvas and the inspector both say it from here.
 */
export function neighbours(
  workflow: Pick<Workflow, "nodes" | "edges">,
  id: string
): { before: string[]; after: { title: string; label?: string }[] } {
  const titles = new Map(workflow.nodes.map((node) => [node.id, node.title]))
  return {
    before: workflow.edges.filter((edge) => edge.to === id).map((edge) => titles.get(edge.from) ?? edge.from),
    after: workflow.edges
      .filter((edge) => edge.from === id)
      .map((edge) => ({ title: titles.get(edge.to) ?? edge.to, ...(edge.label ? { label: edge.label } : {}) })),
  }
}

/** A step as the island draws it: the row, with its icon already drawn on the server. */
export type Step = WorkflowNode & { glyph: React.ReactNode }

/** A workflow as the island holds it. */
export type Flow = Omit<Workflow, "nodes"> & { nodes: Step[] }

/** A workflow can run with exactly one trigger to start it and at least one action to do. */
export function runnable(workflow: Pick<Workflow, "nodes">): boolean {
  const triggers = workflow.nodes.filter((node) => node.kind === "trigger").length
  return triggers === 1 && workflow.nodes.some((node) => node.kind === "action")
}

export type Point = { x: number; y: number }
export type Size = { width: number; height: number }

/** The plane the steps sit on: from the origin to the far corner of the furthest step. */
export function boundsOf(nodes: readonly Point[]): Size {
  return {
    width: Math.max(0, ...nodes.map((node) => node.x)) + NODE_WIDTH,
    height: Math.max(0, ...nodes.map((node) => node.y)) + NODE_HEIGHT,
  }
}

/**
 * The curve from one step's right edge to the next step's left edge, both at
 * mid-height: a cubic whose handles run level out of each end, so a branch
 * leaves and arrives square. `mid` is the curve's halfway point, for a label.
 */
export function edgePath(from: Point, to: Point): { d: string; mid: Point } {
  const x1 = from.x + NODE_WIDTH
  const y1 = from.y + NODE_HEIGHT / 2
  const x2 = to.x
  const y2 = to.y + NODE_HEIGHT / 2
  const reach = Math.max(24, (x2 - x1) / 2)
  return {
    d: `M ${x1} ${y1} C ${x1 + reach} ${y1}, ${x2 - reach} ${y2}, ${x2} ${y2}`,
    mid: { x: (x1 + x2) / 2, y: (y1 + y2) / 2 },
  }
}

/** Where the plane sits in the viewport, and how large it is drawn. */
export type View = { x: number; y: number; zoom: number }

/** A zoom inside the range, to the hundredth, so the readout is a whole percentage. */
export function clampZoom(zoom: number): number {
  return Math.round(Math.min(ZOOM_MAX, Math.max(ZOOM_MIN, zoom)) * 100) / 100
}

/**
 * One press of zoom in `direction`, onto a multiple of ZOOM_STEP: from a
 * fitted 99% the next press in is 100% and the next out 90%, so the readout
 * lands on round figures after a single press.
 */
export function stepZoom(zoom: number, direction: 1 | -1): number {
  const steps = zoom / ZOOM_STEP
  const from = direction === 1 ? Math.floor(steps + 1e-6) : Math.ceil(steps - 1e-6)
  return clampZoom((from + direction) * ZOOM_STEP)
}

/**
 * The view that shows the whole graph with a margin, centred, never larger
 * than `maxZoom`. The zoom rounds down, so the graph always fits inside the
 * margin. A graph too long to fit even at ZOOM_MIN is shown from its start —
 * the trigger's side, where the flow begins — rather than cropped at both ends.
 */
export function fitView(bounds: Size, viewport: Size, maxZoom = ZOOM_MAX, margin = 24): View {
  const room = { width: viewport.width - margin * 2, height: viewport.height - margin * 2 }
  const scale = Math.min(maxZoom, room.width / bounds.width, room.height / bounds.height)
  const zoom = clampZoom(Math.floor(scale * 100 + 1e-6) / 100)
  const place = (length: number, space: number, side: number) =>
    length * zoom <= space - margin * 2 + 1e-6 ? Math.round((space - length * zoom) / 2) : side
  return {
    x: place(bounds.width, viewport.width, margin),
    y: place(bounds.height, viewport.height, margin),
    zoom,
  }
}

/** The smallest zoom a workflow opens at: below it a step's name is too small to read. */
export const OPENING_ZOOM_MIN = 0.8

/**
 * The view a workflow opens in: fitted and centred when the whole graph reads
 * at 80% or more (and never above 100%); a longer one opens at 80% from its
 * trigger, the rest a pan or a Fit away.
 */
export function openingView(bounds: Size, viewport: Size, margin = 24): View {
  const fitted = fitView(bounds, viewport, 1, margin)
  if (fitted.zoom >= OPENING_ZOOM_MIN) return fitted
  return {
    x: margin,
    y: Math.round((viewport.height - bounds.height * OPENING_ZOOM_MIN) / 2),
    zoom: OPENING_ZOOM_MIN,
  }
}

/** The view zoomed to `zoom` about a point of the viewport, which stays where it is on screen. */
export function zoomAround(view: View, zoom: number, center: Point): View {
  const next = clampZoom(zoom)
  const ratio = next / view.zoom
  return {
    x: Math.round(center.x - (center.x - view.x) * ratio),
    y: Math.round(center.y - (center.y - view.y) * ratio),
    zoom: next,
  }
}

"use client"

import * as React from "react"

import { cn } from "@/lib/utils"

import { boundsOf, edgePath, type Flow } from "../flow"

/**
 * The connections, drawn under the steps: a curve from each step to the next
 * that ends in an arrowhead, in the muted ink — the ink itself for the ones
 * that touch the picked step — and a small "yes" or "no" chip where a branch
 * splits. Decoration to a screen reader: each step says where it leads.
 */
export function CanvasEdges({ flow, stepId }: { flow: Flow; stepId: string | null }) {
  const id = React.useId()
  const at = new Map(flow.nodes.map((node) => [node.id, node]))
  const { width, height } = boundsOf(flow.nodes)
  const edges = flow.edges.flatMap((edge) => {
    const from = at.get(edge.from)
    const to = at.get(edge.to)
    if (!from || !to) return []
    return [{ ...edge, ...edgePath(from, to), live: stepId !== null && (edge.from === stepId || edge.to === stepId) }]
  })

  return (
    <>
      <svg
        aria-hidden="true"
        width={width}
        height={height}
        className="pointer-events-none absolute top-0 left-0 overflow-visible text-muted-foreground"
      >
        <defs>
          {(["quiet", "live"] as const).map((tone) => (
            <marker
              key={tone}
              id={`${id}-${tone}`}
              viewBox="0 0 10 10"
              refX="9"
              refY="5"
              markerWidth="7"
              markerHeight="7"
              orient="auto-start-reverse"
              className={tone === "live" ? "text-foreground" : undefined}
            >
              <path d="M 0 1 L 9 5 L 0 9 z" fill="currentColor" />
            </marker>
          ))}
        </defs>
        {edges.map((edge) => (
          <path
            key={`${edge.from}>${edge.to}`}
            data-slot="canvas-edge"
            data-from={edge.from}
            data-to={edge.to}
            data-label={edge.label}
            data-live={edge.live || undefined}
            d={edge.d}
            fill="none"
            stroke="currentColor"
            strokeWidth={1.5}
            markerEnd={`url(#${id}-${edge.live ? "live" : "quiet"})`}
            className={cn(edge.live && "text-foreground")}
          />
        ))}
      </svg>
      {edges
        .filter((edge) => edge.label)
        .map((edge) => (
          <span
            key={`${edge.from}>${edge.to}`}
            aria-hidden="true"
            data-slot="canvas-edge-label"
            className="pointer-events-none absolute -translate-x-1/2 -translate-y-1/2 rounded-full bg-card px-1.5 text-2xs leading-4 font-medium text-muted-foreground ring-1 ring-border"
            style={{ left: edge.mid.x, top: edge.mid.y }}
          >
            {edge.label}
          </span>
        ))}
    </>
  )
}

"use client"

import * as React from "react"

import { formatDuration, formatRelative } from "@/lib/format"
import type { WorkflowRun } from "@/lib/sample-data"
import { Card, CardContent, CardDescription, CardHeader, CardTitle } from "@/components/ui/card"
import { SimpleTable } from "@/components/ui/simple-table"
import { StatusBadge } from "@/components/ui/status-badge"

import { RUN_LABELS, type Flow } from "../flow"

// Pinned to UTC, so a run reads the same wherever the page is opened.
const STARTED = new Intl.DateTimeFormat("en-US", {
  month: "short",
  day: "numeric",
  hour: "2-digit",
  minute: "2-digit",
  hourCycle: "h23",
  timeZone: "UTC",
})

const RUN_TONES = { succeeded: "success", failed: "danger", running: "info" } as const

/** Past a week, "how long ago" is only the date again, which the column already prints. */
const WEEK_MS = 7 * 86_400_000

/** "1.3s" under a minute — a run is seconds of work, and whole seconds would call most of them "1s". */
function took(ms: number): string {
  return ms < 60_000 ? `${(ms / 1000).toFixed(1)}s` : formatDuration(ms)
}

/** "13 succeeded · 2 failed", and a running one when there is one. */
function tally(runs: WorkflowRun[]): string {
  const count = (status: WorkflowRun["status"]) => runs.filter((run) => run.status === status).length
  return (["succeeded", "failed", "running"] as const)
    .filter((status) => count(status) > 0)
    .map((status) => `${count(status)} ${RUN_LABELS[status].toLowerCase()}`)
    .join(" · ")
}

/**
 * The open workflow's runs, newest first: the run's id, when it started,
 * how long it took and how it ended. A run started from the page is in the
 * book with its outcome from the start; `playing` names the ones the page
 * still shows running while they play out.
 */
export function RunHistory({ flow, now, playing }: { flow: Flow; now: Date; playing: ReadonlySet<string> }) {
  const titleId = React.useId()
  const shown = flow.runs.map((run): WorkflowRun => (playing.has(run.id) ? { ...run, status: "running" } : run))
  const runs = [...shown].reverse()

  return (
    <Card role="region" aria-labelledby={titleId}>
      <CardHeader>
        <CardTitle>
          <h2 id={titleId}>Run history</h2>
        </CardTitle>
        <CardDescription className="tabular-nums">
          {runs.length ? `${runs.length} ${runs.length === 1 ? "run" : "runs"}, newest first · ${tally(shown)}` : "No runs yet"}
        </CardDescription>
      </CardHeader>
      <CardContent className="p-0">
        <SimpleTable
          className="rounded-none border-0"
          rows={runs}
          rowKey="id"
          emptyMessage={flow.status === "draft" ? "A draft has never run. Switch it on, or run it now once it has a trigger." : "Nothing has run yet."}
          columns={[
            {
              key: "id",
              header: "Run",
              cell: (run) => <span className="font-mono text-xs">{run.id}</span>,
            },
            {
              key: "startedAt",
              header: "Started",
              cell: (run) => (
                <time dateTime={run.startedAt.toISOString()} className="flex flex-col tabular-nums sm:flex-row sm:gap-2">
                  <span>{STARTED.format(run.startedAt)}</span>
                  {now.getTime() - run.startedAt.getTime() < WEEK_MS ? (
                    <span className="text-xs text-muted-foreground sm:text-sm">{formatRelative(run.startedAt, now)}</span>
                  ) : null}
                </time>
              ),
            },
            {
              key: "durationMs",
              header: "Duration",
              align: "right",
              // A phone has no room for the column; the time rides under the status instead.
              className: "max-sm:hidden",
              cell: (run) => (run.status === "running" ? "—" : took(run.durationMs)),
            },
            {
              key: "status",
              header: "Status",
              cell: (run) => (
                <span className="flex flex-col items-start gap-0.5">
                  <StatusBadge
                    status={run.status}
                    label={RUN_LABELS[run.status]}
                    variant={RUN_TONES[run.status]}
                    pulse={run.status === "running"}
                  />
                  {run.status === "running" ? null : (
                    <span className="text-xs text-muted-foreground tabular-nums sm:hidden">
                      {took(run.durationMs)}
                    </span>
                  )}
                </span>
              ),
            },
          ]}
        />
      </CardContent>
    </Card>
  )
}

"use client"

import * as React from "react"

import type { Result } from "@/lib/sample-data"
import { Button } from "@/components/ui/button"
import { Callout } from "@/components/ui/callout"
import { DescriptionList } from "@/components/ui/description-list"
import { InspectorPanel } from "@/components/ui/inspector-panel"
import { Input } from "@/components/ui/input"
import { Label } from "@/components/ui/label"

import { KIND_LABELS, neighbours, type Flow, type Step } from "../flow"

/** The step's name, the one thing about it the page lets you change. */
function RenameForm({
  step,
  onRename,
}: {
  step: Step
  onRename: (nodeId: string, title: string) => Promise<Result<{ title: string }>>
}) {
  const inputId = React.useId()
  const alertId = React.useId()
  const [draft, setDraft] = React.useState(step.title)
  const [pending, setPending] = React.useState(false)
  const [notice, setNotice] = React.useState("")
  const [refusal, setRefusal] = React.useState("")

  async function submit(event: React.FormEvent<HTMLFormElement>) {
    event.preventDefault()
    setPending(true)
    setNotice("")
    setRefusal("")
    const result = await onRename(step.id, draft)
    setPending(false)
    if (!result.ok) return setRefusal(result.error.message)
    setDraft(result.data.title)
    setNotice(`Renamed to “${result.data.title}”.`)
  }

  return (
    <form data-slot="step-rename" className="flex flex-col gap-2" onSubmit={submit}>
      <Label htmlFor={inputId}>Name</Label>
      <div className="flex gap-2">
        <Input
          id={inputId}
          value={draft}
          autoComplete="off"
          onChange={(event) => setDraft(event.target.value)}
          aria-invalid={refusal ? true : undefined}
          aria-describedby={refusal ? alertId : undefined}
        />
        <Button type="submit" variant="outline" disabled={pending} focusableWhenDisabled>
          Rename
        </Button>
      </div>
      {refusal ? (
        <Callout id={alertId} variant="danger" role="alert">
          {refusal}
        </Callout>
      ) : null}
      <p role="status" aria-live="polite" className="min-h-4 text-xs text-muted-foreground">
        {notice}
      </p>
    </form>
  )
}

export type StepInspectorProps = {
  flow: Flow
  step: Step | null
  mode: "inline" | "overlay"
  onClose: () => void
  onRename: (nodeId: string, title: string) => Promise<Result<{ title: string }>>
}

/**
 * The picked step, beside the canvas — or over it as a sheet on a narrow
 * page. Its name can be changed here; what kind of step it is, what it does
 * and what it sits between are read-only, because the graph is the
 * workflow's and the canvas only draws it.
 */
export function StepInspector({ flow, step, mode, onClose, onRename }: StepInspectorProps) {
  // The panel outlives the pick by one animation, so the last step stays drawn while it closes.
  const [last, setLast] = React.useState(step)
  if (step && step !== last) setLast(step)
  const shown = step ?? (last && flow.nodes.find((node) => node.id === last.id)) ?? null
  if (!shown) return null

  const { before, after: ways } = neighbours(flow, shown.id)
  const after = ways.map(({ title, label }) => `${title}${label ? ` (${label})` : ""}`)

  return (
    <InspectorPanel
      open={step !== null}
      onOpenChange={(open) => {
        if (!open) onClose()
      }}
      mode={mode}
      width="sm"
      title={shown.title}
      description={`${KIND_LABELS[shown.kind]} · ${flow.name}`}
      className="min-h-full"
    >
      <div className="flex flex-col gap-5">
        <RenameForm key={shown.id} step={shown} onRename={onRename} />
        <DescriptionList
          size="sm"
          orientation="vertical"
          items={[
            { term: "Step", description: KIND_LABELS[shown.kind] },
            { term: "What it does", description: shown.summary },
            {
              term: "Comes after",
              description: before.length ? before.join(", ") : "Nothing — it starts the workflow",
            },
            {
              term: "Goes to",
              description: after.length ? after.join(", ") : "Nothing — the workflow ends here",
            },
          ]}
        />
      </div>
    </InspectorPanel>
  )
}

"use client"

import * as React from "react"

import { cn } from "@/lib/utils"

import { KIND_LABELS, NODE_HEIGHT, NODE_WIDTH, neighbours, type Flow, type Step } from "../flow"

/** "Leads to Post to #big-orders if yes, Post to #orders if no." — where a step goes, for a screen reader. */
export function leadsTo(flow: Flow, step: Step): string {
  const next = neighbours(flow, step.id).after.map(({ title, label }) => `${title}${label ? ` if ${label}` : ""}`)
  return next.length ? `Leads to ${next.join(", ")}.` : "Ends the workflow."
}

export type StepNodeProps = {
  flow: Flow
  step: Step
  selected: boolean
  onSelect: () => void
  /** Focus landed on the step: the canvas moves it clear of what covers it. */
  onFocus?: () => void
}

/**
 * One step, drawn where the workflow puts it: a framed card with its icon,
 * what kind of step it is, its name and a line of what it does. It is a
 * button — press it to open the step in the inspector, again to close it —
 * and the picked one wears the chosen fill rather than an outline.
 */
export function StepNode({ flow, step, selected, onSelect, onFocus }: StepNodeProps) {
  const describedBy = React.useId()
  return (
    <button
      type="button"
      data-slot="canvas-step"
      data-kind={step.kind}
      data-selected={selected || undefined}
      aria-label={step.title}
      aria-pressed={selected}
      aria-describedby={describedBy}
      onClick={onSelect}
      onFocus={onFocus}
      className={cn(
        "absolute flex items-start gap-3 rounded-lg bg-card p-3 text-left ring-1 ring-border transition-colors duration-(--duration-fast) ease-(--ease-standard) focus-ring",
        "hover:bg-accent/60 data-selected:bg-brand-muted data-selected:hover:bg-brand-muted"
      )}
      style={{ left: step.x, top: step.y, width: NODE_WIDTH, height: NODE_HEIGHT }}
    >
      <span
        aria-hidden="true"
        className={cn(
          "grid size-8 shrink-0 place-items-center rounded-md [&_svg]:size-4",
          step.kind === "trigger" ? "bg-foreground text-background" : "bg-secondary text-foreground"
        )}
      >
        {step.glyph}
      </span>
      <span className="flex min-w-0 flex-col">
        <span className="text-xs text-muted-foreground">{KIND_LABELS[step.kind]}</span>
        <span className="truncate text-sm font-semibold text-foreground">{step.title}</span>
        <span className="truncate text-xs text-muted-foreground">{step.summary}</span>
      </span>
      <span id={describedBy} className="sr-only">
        {`${KIND_LABELS[step.kind]}. ${step.summary}. ${leadsTo(flow, step)}`}
      </span>
    </button>
  )
}

"use client"

import * as React from "react"
import { MinusIcon, PlusIcon } from "lucide-react"

import { cn } from "@/lib/utils"
import { Button } from "@/components/ui/button"

import {
  NODE_HEIGHT,
  NODE_WIDTH,
  PAN_STEP,
  PAN_STEP_LARGE,
  ZOOM_MAX,
  ZOOM_MIN,
  boundsOf,
  fitView,
  openingView,
  stepZoom,
  zoomAround,
  type Flow,
  type Step,
  type View,
} from "../flow"
import { CanvasEdges } from "./canvas-edges"
import { StepNode } from "./step-node"

/** Where the plane opens before the viewport has been measured: at 100%, a margin in. */
const START: View = { x: 24, y: 24, zoom: 1 }

/** How close to the viewport's edge a step revealed by the inspector may sit. */
const EDGE = 16

export type WorkflowCanvasProps = {
  flow: Flow
  stepId: string | null
  onStep: (id: string | null) => void
  /** What the page's last action did, said in the line under the plane. */
  notice: string
  /** How much of the plane's right side the inspector covers once a step is open, so the step is moved clear of it. */
  covered?: number
  /** Laid over the plane's right side: the inspector, on a wide page. */
  children?: React.ReactNode
}

/**
 * The open workflow as a graph on a plane that pans and zooms. The plane is
 * the sheet itself — no dots, no grid — and the steps sit on it where the
 * workflow puts them, joined by curves that end in an arrowhead. Drag the
 * plane, or focus it and use the arrow keys (Shift for bigger steps), to
 * pan; − and + zoom between 20% and 150% and Fit shows the whole graph, from
 * the buttons or the keys. It opens fitted, between 80% and 100% — a long
 * graph at 80% from its trigger. A picked step, and a step reached with Tab,
 * is moved into view clear of the inspector. The pan is the one truth of
 * where the plane sits: the viewport clips and never scrolls, so the browser
 * cannot shift the plane behind it.
 */
export function WorkflowCanvas({ flow, stepId, onStep, notice, covered = 0, children }: WorkflowCanvasProps) {
  const viewportRef = React.useRef<HTMLDivElement>(null)
  const drag = React.useRef<{ pointer: number; fromX: number; fromY: number; x: number; y: number } | null>(null)
  const [view, setView] = React.useState<View>(START)
  const [gliding, setGliding] = React.useState(false)
  const [dragging, setDragging] = React.useState(false)
  const hintId = React.useId()
  const bounds = React.useMemo(() => boundsOf(flow.nodes), [flow.nodes])

  // Left to right, then top to bottom: the order the flow runs in is the order Tab walks it.
  const steps = React.useMemo(() => [...flow.nodes].sort((a, b) => a.x - b.x || a.y - b.y), [flow.nodes])

  const measure = React.useCallback(() => {
    const box = viewportRef.current?.getBoundingClientRect()
    return box && box.width > 0 && box.height > 0 ? { width: box.width, height: box.height } : null
  }, [])

  // Placed once, the first time the viewport has a size: the whole graph
  // when it reads, the start of a long one when it would not. Only once — a
  // rename or a resize afterwards leaves the reader's pan and zoom alone.
  const placed = React.useRef(false)
  React.useEffect(() => {
    const node = viewportRef.current
    if (!node || typeof ResizeObserver === "undefined") return
    const observer = new ResizeObserver(([entry]) => {
      const { width, height } = entry.contentRect
      if (placed.current || width <= 0 || height <= 0) return
      placed.current = true
      setView(openingView(bounds, { width, height }))
    })
    observer.observe(node)
    return () => observer.disconnect()
  }, [bounds])

  function zoomTo(direction: 1 | -1) {
    const size = measure()
    setGliding(true)
    setView((current) =>
      zoomAround(current, stepZoom(current.zoom, direction), size ? { x: size.width / 2, y: size.height / 2 } : { x: 0, y: 0 })
    )
  }

  function fit() {
    const size = measure()
    setGliding(true)
    setView(size ? fitView(bounds, size) : START)
  }

  function panBy(dx: number, dy: number) {
    setGliding(true)
    setView((current) => ({ ...current, x: current.x + dx, y: current.y + dy }))
  }

  /** Moves the plane just enough that `step` sits inside the part of the viewport `cover` leaves. */
  function reveal(step: Step, cover: number) {
    const size = measure()
    if (!size) return
    setGliding(true)
    setView((current) => {
      const left = current.x + step.x * current.zoom
      const top = current.y + step.y * current.zoom
      const right = left + NODE_WIDTH * current.zoom
      const bottom = top + NODE_HEIGHT * current.zoom
      const room = size.width - cover - EDGE
      let dx = right > room ? room - right : 0
      if (left + dx < EDGE) dx = EDGE - left
      let dy = bottom > size.height - EDGE ? size.height - EDGE - bottom : 0
      if (top + dy < EDGE) dy = EDGE - top
      return dx || dy ? { ...current, x: current.x + dx, y: current.y + dy } : current
    })
  }

  function select(step: Step) {
    if (step.id === stepId) return onStep(null)
    onStep(step.id)
    reveal(step, covered)
  }

  // A step focused by a press is about to be picked, and the pick moves it;
  // one reached from the keyboard is moved clear as focus lands on it, of the
  // inspector too while a step is open.
  const pressing = React.useRef(false)
  function focusStep(step: Step) {
    if (!pressing.current) reveal(step, stepId ? covered : 0)
  }

  function onKeyDown(event: React.KeyboardEvent<HTMLDivElement>) {
    // Keys belong to the plane only while it has focus itself, not a step on it.
    if (event.target !== event.currentTarget) return
    const step = event.shiftKey ? PAN_STEP_LARGE : PAN_STEP
    const keys: Record<string, () => void> = {
      ArrowLeft: () => panBy(step, 0),
      ArrowRight: () => panBy(-step, 0),
      ArrowUp: () => panBy(0, step),
      ArrowDown: () => panBy(0, -step),
      "+": () => zoomTo(1),
      "=": () => zoomTo(1),
      "-": () => zoomTo(-1),
      "0": fit,
    }
    const act = keys[event.key]
    if (!act) return
    event.preventDefault()
    act()
  }

  function onPointerDown(event: React.PointerEvent<HTMLDivElement>) {
    if (event.button !== 0 || (event.target as Element).closest("button")) return
    event.currentTarget.setPointerCapture?.(event.pointerId)
    drag.current = { pointer: event.pointerId, fromX: event.clientX, fromY: event.clientY, x: view.x, y: view.y }
    setGliding(false)
    setDragging(true)
  }

  function onPointerMove(event: React.PointerEvent<HTMLDivElement>) {
    const start = drag.current
    if (!start || start.pointer !== event.pointerId) return
    setView((current) => ({ ...current, x: start.x + event.clientX - start.fromX, y: start.y + event.clientY - start.fromY }))
  }

  function endDrag(event: React.PointerEvent<HTMLDivElement>) {
    if (drag.current?.pointer !== event.pointerId) return
    drag.current = null
    setDragging(false)
  }

  return (
    <div data-slot="workflow-canvas-frame" className="flex min-w-0 flex-1 flex-col">
      <div className="relative">
        <div
          ref={viewportRef}
          role="group"
          aria-roledescription="canvas"
          aria-label={`${flow.name}, ${flow.nodes.length} steps`}
          aria-describedby={hintId}
          tabIndex={0}
          data-slot="workflow-canvas"
          data-zoom={view.zoom}
          data-pan-x={Math.round(view.x)}
          data-pan-y={Math.round(view.y)}
          data-dragging={dragging || undefined}
          onKeyDown={onKeyDown}
          onPointerDownCapture={() => {
            pressing.current = true
          }}
          onPointerDown={onPointerDown}
          onPointerMove={onPointerMove}
          onPointerUp={endDrag}
          onPointerUpCapture={() => {
            pressing.current = false
          }}
          onPointerCancel={(event) => {
            pressing.current = false
            endDrag(event)
          }}
          className="relative h-72 cursor-grab touch-none overflow-clip rounded-t-lg select-none focus-ring-inset data-dragging:cursor-grabbing sm:h-96"
        >
          <div
            data-slot="workflow-plane"
            className={cn(
              "absolute top-0 left-0 origin-top-left",
              gliding && "transition-transform duration-(--duration-base) ease-(--ease-standard)"
            )}
            style={{ width: bounds.width, height: bounds.height, transform: `translate(${view.x}px, ${view.y}px) scale(${view.zoom})` }}
          >
            <CanvasEdges flow={flow} stepId={stepId} />
            {steps.map((step) => (
              <StepNode
                key={step.id}
                flow={flow}
                step={step}
                selected={step.id === stepId}
                onSelect={() => select(step)}
                onFocus={() => focusStep(step)}
              />
            ))}
          </div>
        </div>
        {children ? <div className="absolute inset-y-0 right-0 flex">{children}</div> : null}
      </div>

      <div className="flex flex-wrap items-center justify-between gap-x-4 gap-y-2 border-t border-border px-3 py-2">
        <div role="toolbar" aria-label="Zoom" className="flex items-center gap-1">
          <Button
            variant="outline"
            size="icon-sm"
            aria-label="Zoom out"
            aria-keyshortcuts="-"
            // Focusable at the end of the range, so the press that reaches it keeps focus.
            disabled={view.zoom <= ZOOM_MIN}
            focusableWhenDisabled
            onClick={() => zoomTo(-1)}
          >
            <MinusIcon />
          </Button>
          <output aria-label="Zoom level" className="min-w-12 text-center text-xs font-medium tabular-nums">
            {`${Math.round(view.zoom * 100)}%`}
          </output>
          <Button
            variant="outline"
            size="icon-sm"
            aria-label="Zoom in"
            aria-keyshortcuts="+"
            disabled={view.zoom >= ZOOM_MAX}
            focusableWhenDisabled
            onClick={() => zoomTo(1)}
          >
            <PlusIcon />
          </Button>
          <Button variant="outline" size="sm" aria-keyshortcuts="0" className="ml-1" onClick={fit}>
            Fit
          </Button>
        </div>
        <div className="min-w-0 text-xs text-muted-foreground sm:text-right">
          {/* Always mounted, so it is heard when it fills; while it has nothing
              to say, the hint for the plane takes its place on screen. */}
          <p data-slot="workflow-notice" role="status" aria-live="polite" className={notice ? undefined : "sr-only"}>
            {notice}
          </p>
          <p id={hintId} className={notice ? "sr-only" : undefined}>
            Drag the plane, or focus it and use the arrow keys, to pan; − and + zoom, and 0 fits the graph.
          </p>
        </div>
      </div>
    </div>
  )
}

"use client"

import * as React from "react"
import { PlayIcon } from "lucide-react"

import type { Result } from "@/lib/sample-data"
import { AsyncButton } from "@/components/ui/async-button"
import { Callout } from "@/components/ui/callout"
import { Card, CardAction, CardContent, CardDescription, CardHeader, CardTitle } from "@/components/ui/card"
import { Label } from "@/components/ui/label"
import { StatusBadge } from "@/components/ui/status-badge"
import { Switch } from "@/components/ui/switch"

import { STATUS_LABELS, type Flow } from "../flow"
import { StepInspector } from "./step-inspector"
import { WorkflowCanvas } from "./workflow-canvas"
import { lastRun } from "./workflow-list"

/** The inspector's width over the plane: InspectorPanel's "sm", 20rem. */
const INSPECTOR_WIDTH = 320

export type WorkflowCardProps = {
  flow: Flow
  stepId: string | null
  onStep: (id: string | null) => void
  /** Beside the canvas on a wide page, over it as a sheet on a narrow one. */
  inspector: "inline" | "overlay"
  onToggle: (on: boolean) => Promise<void>
  onRun: () => Promise<void>
  onRename: (nodeId: string, title: string) => Promise<Result<{ title: string }>>
  notice: string
  refusal: string
  now: Date
}

/**
 * The open workflow: its name, whether it is on and a way to run it now in
 * the strip; the canvas in the sheet, with the inspector for the picked step
 * beside it; and what the last action did in the line under the plane. A
 * refusal is said under the strip, by the switch and the button that asked.
 */
export function WorkflowCard({
  flow,
  stepId,
  onStep,
  inspector,
  onToggle,
  onRun,
  onRename,
  notice,
  refusal,
  now,
}: WorkflowCardProps) {
  const titleId = React.useId()
  const switchId = React.useId()
  const step = flow.nodes.find((node) => node.id === stepId) ?? null
  const steps = flow.nodes.length
  // Laid over the plane's right side on a wide page, so opening it never
  // squeezes the graph; a sheet over the page on a narrow one.
  const panel = (
    <StepInspector flow={flow} step={step} mode={inspector} onClose={() => onStep(null)} onRename={onRename} />
  )

  return (
    <Card role="region" aria-labelledby={titleId}>
      <CardHeader className="max-sm:has-data-[slot=card-action]:grid-cols-1">
        <CardTitle className="flex min-w-0 items-center gap-2">
          <h2 id={titleId} className="truncate">
            {flow.name}
          </h2>
          <StatusBadge status={flow.status} label={STATUS_LABELS[flow.status]} size="sm" />
        </CardTitle>
        <CardDescription className="tabular-nums">{`${steps} steps · ${lastRun(flow, now)}`}</CardDescription>
        <CardAction className="flex items-center gap-3 max-sm:col-start-1 max-sm:row-span-1 max-sm:row-start-3 max-sm:justify-self-start">
          <span className="flex items-center gap-2">
            <Switch
              id={switchId}
              checked={flow.status === "active"}
              onCheckedChange={(checked) => void onToggle(checked)}
            />
            <Label htmlFor={switchId} className="text-sm">
              Active
            </Label>
          </span>
          <AsyncButton variant="outline" size="sm" onClick={onRun}>
            <PlayIcon data-icon="inline-start" />
            Run now
          </AsyncButton>
        </CardAction>
      </CardHeader>

      {refusal ? (
        <div className="px-(--card-spacing) pb-2">
          <Callout variant="danger" role="alert">
            {refusal}
          </Callout>
        </div>
      ) : null}

      <CardContent className="flex p-0">
        <WorkflowCanvas
          flow={flow}
          stepId={stepId}
          onStep={onStep}
          notice={notice}
          covered={inspector === "inline" ? INSPECTOR_WIDTH : 0}
        >
          {inspector === "inline" ? panel : null}
        </WorkflowCanvas>
        {inspector === "overlay" ? panel : null}
      </CardContent>
    </Card>
  )
}

"use client"

import * as React from "react"

import { cn } from "@/lib/utils"
import { formatRelative } from "@/lib/format"
import { Card, CardContent, CardDescription, CardHeader, CardTitle } from "@/components/ui/card"
import { Label } from "@/components/ui/label"
import { Select, SelectContent, SelectItem, SelectTrigger, SelectValue } from "@/components/ui/select"
import { StatusBadge } from "@/components/ui/status-badge"

import { STATUS_LABELS, type Flow } from "../flow"

/** "Last run 2h ago", or "Never run" for a workflow with no runs. */
export function lastRun(flow: Flow, now: Date): string {
  const latest = flow.runs[flow.runs.length - 1]
  return latest ? `Last run ${formatRelative(latest.startedAt, now)}` : "Never run"
}

/** "5 active · 1 paused · 2 drafts". */
function tally(flows: Flow[]): string {
  const count = (status: Flow["status"]) => flows.filter((flow) => flow.status === status).length
  const drafts = count("draft")
  return `${count("active")} active · ${count("paused")} paused · ${drafts} ${drafts === 1 ? "draft" : "drafts"}`
}

export type WorkflowListProps = {
  flows: Flow[]
  openId: string
  now: Date
  onOpen: (id: string) => void
  className?: string
}

/**
 * Every workflow, beside the canvas from 1280px: its name, whether it is on
 * and when it last ran. The open one wears the chosen fill, a rail and the
 * heavier weight — three cues, never the colour alone.
 */
export function WorkflowList({ flows, openId, now, onOpen, className }: WorkflowListProps) {
  const titleId = React.useId()
  return (
    <Card role="region" aria-labelledby={titleId} className={cn("xl:sticky xl:top-20", className)}>
      <CardHeader>
        <CardTitle>
          <h2 id={titleId}>Workflows</h2>
        </CardTitle>
        <CardDescription className="tabular-nums">{tally(flows)}</CardDescription>
      </CardHeader>
      <CardContent className="p-1.5">
        <ul className="flex flex-col gap-0.5">
          {flows.map((flow) => {
            const open = flow.id === openId
            return (
              <li key={flow.id}>
                <button
                  type="button"
                  aria-current={open ? "true" : undefined}
                  onClick={() => onOpen(flow.id)}
                  className={cn(
                    "flex w-full flex-col items-start gap-1 rounded-md px-2.5 py-2 text-left transition-colors duration-(--duration-fast) ease-(--ease-standard) focus-ring hover:bg-muted/60",
                    open && "bg-brand-muted font-medium shadow-[inset_2px_0_0_var(--brand)] hover:bg-brand-muted"
                  )}
                >
                  <span className="flex w-full items-center justify-between gap-2">
                    <span className="truncate text-sm">{flow.name}</span>
                    <StatusBadge status={flow.status} label={STATUS_LABELS[flow.status]} size="sm" />
                  </span>
                  <span className="text-xs font-normal text-muted-foreground tabular-nums">{lastRun(flow, now)}</span>
                </button>
              </li>
            )
          })}
        </ul>
      </CardContent>
    </Card>
  )
}

/** The same choice on a phone, where there is no room for a list beside the canvas. */
export function WorkflowPicker({ flows, openId, onOpen, className }: Omit<WorkflowListProps, "now">) {
  const labelId = React.useId()
  const items = flows.map((flow) => ({ value: flow.id, label: flow.name }))
  return (
    <div data-slot="workflow-picker" className={cn("flex flex-col gap-1.5", className)}>
      <Label id={labelId} className="text-xs text-muted-foreground">
        Workflow
      </Label>
      <Select value={openId} onValueChange={(next) => next && onOpen(next as string)} items={items}>
        <SelectTrigger aria-labelledby={labelId} className="h-9 w-full">
          <SelectValue />
        </SelectTrigger>
        <SelectContent>
          {flows.map((flow) => (
            <SelectItem key={flow.id} value={flow.id}>
              <span className="truncate">{flow.name}</span>
              <span className="text-muted-foreground">{STATUS_LABELS[flow.status]}</span>
            </SelectItem>
          ))}
        </SelectContent>
      </Select>
    </div>
  )
}

"use client"

import * as React from "react"

import { useMediaQuery } from "@/hooks/use-media-query"
import { prefersReducedMotion } from "@/hooks/use-reduced-motion"
import type { Result, WorkflowRun } from "@/lib/sample-data"

import { renameStep, runWorkflow, setWorkflowStatus } from "../actions"
import { RUN_MS, type Flow } from "../flow"
import { RunHistory } from "./run-history"
import { WorkflowCard } from "./workflow-card"
import { WorkflowList, WorkflowPicker } from "./workflow-list"

/**
 * The workflows page's one island. It holds the book as the actions last left
 * it, which workflow is open and which of its steps is picked; the list, the
 * canvas, the inspector and the run history all read from here, so a rename,
 * a switch or a run shows everywhere at once. The list stands beside the
 * canvas from 1280px — below that it is a select above it, so the canvas
 * keeps the width — and the inspector lies over the canvas from 1024px, a
 * sheet below.
 */
export function WorkflowsView({ workflows, now }: { workflows: Flow[]; now: Date }) {
  const [flows, setFlows] = React.useState(workflows)
  const [openId, setOpenId] = React.useState(workflows[0]?.id ?? "")
  const [stepId, setStepId] = React.useState<string | null>(null)
  const [notice, setNotice] = React.useState("")
  const [refusal, setRefusal] = React.useState("")
  const wide = useMediaQuery("(min-width: 64rem)")

  const flow = flows.find((candidate) => candidate.id === openId) ?? flows[0]

  // A run started here is in the book with its outcome already; the page
  // plays it out as running for as long as a run takes, then shows how it
  // ended. Leaving the page stops the clocks, and the book needs nothing.
  const [playing, setPlaying] = React.useState<ReadonlySet<string>>(() => new Set())
  const clocks = React.useRef(new Set<ReturnType<typeof setTimeout>>())
  React.useEffect(() => {
    const pending = clocks.current
    return () => {
      for (const clock of pending) clearTimeout(clock)
      pending.clear()
    }
  }, [])

  function patch(workflowId: string, change: (current: Flow) => Flow) {
    setFlows((current) => current.map((candidate) => (candidate.id === workflowId ? change(candidate) : candidate)))
  }

  function putRun(workflowId: string, run: WorkflowRun) {
    patch(workflowId, (current) => ({
      ...current,
      runs: current.runs.some((candidate) => candidate.id === run.id)
        ? current.runs.map((candidate) => (candidate.id === run.id ? run : candidate))
        : [...current.runs, run],
    }))
  }

  function open(id: string) {
    setOpenId(id)
    setStepId(null)
    setNotice("")
    setRefusal("")
  }

  async function toggle(on: boolean) {
    setNotice("")
    setRefusal("")
    const result = await setWorkflowStatus(flow.id, on ? "active" : "paused")
    if (!result.ok) return setRefusal(result.error.message)
    patch(flow.id, (current) => ({ ...current, status: result.data.status }))
    setNotice(
      result.data.status === "active"
        ? `${flow.name} is on — it runs every time its trigger fires.`
        : `${flow.name} is paused — nothing runs until it is switched back on.`
    )
  }

  async function run() {
    setNotice("")
    setRefusal("")
    const name = flow.name
    const result = await runWorkflow(flow.id)
    if (!result.ok) return setRefusal(result.error.message)
    const { workflowId, run: done } = result.data
    putRun(workflowId, done)
    const ended = `${done.id} of ${name} ${done.status === "failed" ? "failed" : "succeeded"}.`

    // Asked for less motion, the history goes straight to how it ended.
    if (prefersReducedMotion()) return setNotice(ended)
    setNotice(`${done.id} started.`)
    setPlaying((current) => new Set(current).add(done.id))
    const clock = setTimeout(() => {
      clocks.current.delete(clock)
      setPlaying((current) => {
        const next = new Set(current)
        next.delete(done.id)
        return next
      })
      setNotice(ended)
    }, RUN_MS)
    clocks.current.add(clock)
  }

  async function rename(nodeId: string, title: string): Promise<Result<{ title: string }>> {
    const result = await renameStep(flow.id, nodeId, title)
    if (!result.ok) return result
    patch(result.data.workflowId, (current) => ({
      ...current,
      nodes: current.nodes.map((node) => (node.id === result.data.nodeId ? { ...node, title: result.data.title } : node)),
    }))
    return { ok: true, data: { title: result.data.title } }
  }

  if (!flow) return null

  return (
    <div data-slot="workflows" className="grid items-start gap-6 xl:grid-cols-[17rem_minmax(0,1fr)]">
      <WorkflowList className="hidden xl:flex" flows={flows} openId={flow.id} now={now} onOpen={open} />
      <div className="flex min-w-0 flex-col gap-6">
        <WorkflowPicker className="xl:hidden" flows={flows} openId={flow.id} onOpen={open} />
        <WorkflowCard
          key={flow.id}
          flow={flow}
          stepId={stepId}
          onStep={setStepId}
          inspector={wide ? "inline" : "overlay"}
          onToggle={toggle}
          onRun={run}
          onRename={rename}
          notice={notice}
          refusal={refusal}
          now={now}
        />
        <RunHistory flow={flow} now={now} playing={playing} />
      </div>
    </div>
  )
}