import { Effect } from "effect"
import { defineScript, Llm } from "opencode-drive"
import { mkdir } from "node:fs/promises"
import path from "node:path"

export default defineScript({
  launch: "manual",
  config: { autoupdate: false },
  run: ({ artifacts, llm, server }) =>
    Effect.gen(function* () {
      yield* Effect.promise(() => configureServicePort(artifacts))
      yield* server.launch()

      const registration = yield* Effect.promise(() => serviceRegistration(artifacts))
      const root = path.resolve(import.meta.dir, "../../../..")
      const preload = Bun.resolveSync("@opentui/solid/preload", path.join(root, "packages/cli"))
      const session = `mini-stage2-${process.pid}`
      const snapshots = path.join(artifacts, "mini-stage2")
      const explicitDirectory = path.join(artifacts, "explicit-model")
      yield* Effect.promise(() => Promise.all([snapshots, explicitDirectory].map((dir) => mkdir(dir, { recursive: true }))))
      /** @param {string} directory @param {string | undefined} model */
      const mini = (directory, model) => [
        "env",
        `PWD=${directory}`,
        `OPENCODE_PASSWORD=${registration.password}`,
        `OPENCODE_CONFIG_DIR=${path.join(artifacts, "files/.opencode")}`,
        `OPENCODE_TEST_HOME=${artifacts}`,
        `XDG_CACHE_HOME=${path.join(artifacts, "home/.cache")}`,
        `XDG_CONFIG_HOME=${path.join(artifacts, "home/.config")}`,
        `XDG_DATA_HOME=${path.join(artifacts, "logs")}`,
        `XDG_STATE_HOME=${path.join(artifacts, "home/.local/state")}`,
        "OPENCODE_DISABLE_AUTOUPDATE=1",
        "OPENCODE_DIRECT_TRACE=1",
        process.execPath,
        "--conditions=browser",
        `--preload=${preload}`,
        path.join(root, "packages/cli/src/index.ts"),
        "mini",
        "--server",
        registration.url,
        ...(model ? ["--model", model] : []),
      ]

      yield* llm.queue(
        Llm.toolCall({
          index: 0,
          id: "mini-shell",
          name: "shell",
          input: { command: "printf 'drive-mini-tool-output\\n'" },
        }),
        Llm.finish("tool-calls"),
      )
      yield* llm.queue(Llm.text("drive mini response complete", { delay: 5, chunkSize: 4 }))

      const journey = Effect.gen(function* () {
        yield* Effect.uninterruptible(
          Effect.promise(() =>
            tmux([
              "new-session",
              "-d",
              "-s",
              session,
              "-x",
              "140",
              "-y",
              "30",
              "--",
              ...mini(path.join(artifacts, "files"), undefined),
            ]),
          ),
        )
        yield* Effect.promise(() => tmux(["set-option", "-t", session, "remain-on-exit", "on"]))

        const first = yield* Effect.promise(() => waitForPane(session, "OpenCode"))
        yield* Effect.promise(() => Bun.write(path.join(snapshots, "01-first-paint.txt"), first))
        if (first.includes("drive mini response complete"))
          throw new Error("response rendered before prompt submission")

        yield* Effect.promise(() => waitForPane(session, "Default model", 15_000))
        yield* Effect.promise(() => tmux(["send-keys", "-t", session, "C-p"]))
        yield* Effect.promise(() => waitForVisiblePane(session, "Commands"))
        yield* Effect.promise(() => tmux(["send-keys", "-t", session, "-l", "model"]))
        yield* Effect.promise(() => waitForVisiblePane(session, "Switch model"))
        yield* Effect.promise(() => tmux(["send-keys", "-H", "-t", session, "0d"]))
        yield* Effect.promise(() => waitForVisiblePane(session, "Select model"))
        yield* Effect.promise(() => waitForVisiblePane(session, "Simulated Model", 15_000))
        yield* Effect.promise(() => tmux(["send-keys", "-t", session, "Escape"]))
        yield* Effect.promise(() => waitForVisiblePane(session, "Ask anything..."))
        yield* Effect.promise(() => tmux(["send-keys", "-t", session, "-l", "exercise the mini frontend"]))
        yield* Effect.sleep(100)
        yield* Effect.promise(() => tmux(["send-keys", "-H", "-t", session, "0d"]))
        const completed = yield* Effect.promise(() => waitForPane(session, "drive mini response complete", 20_000))
        if (!completed.includes("drive-mini-tool-output")) throw new Error("shell tool output was not rendered")
        yield* Effect.promise(() => Bun.write(path.join(snapshots, "02-tool-and-response.txt"), completed))

        yield* Effect.sleep(500)
        const resizeOutput = path.join(snapshots, "03-resize-output.ansi")
        yield* Effect.promise(() => tmux(["pipe-pane", "-t", session, `cat > ${JSON.stringify(resizeOutput)}`]))
        yield* Effect.promise(() => tmux(["resize-window", "-t", session, "-x", "72", "-y", "22"]))
        yield* Effect.promise(() =>
          waitForFile(
            resizeOutput,
            (value) => value.includes("drive mini response complete") && value.includes("drive-mini-tool-output"),
          ),
        )
        yield* Effect.promise(() => tmux(["pipe-pane", "-t", session]))
        const resized = yield* Effect.promise(() => captureVisiblePane(session))
        if (!resized.includes("drive-mini-tool-output")) throw new Error("resize replay lost shell tool output")
        yield* Effect.promise(() => Bun.write(path.join(snapshots, "03-resize-replay.txt"), resized))

        yield* llm.queue(
          Llm.toolCall({
            index: 0,
            id: "mini-question",
            name: "question",
            input: {
              questions: [
                {
                  header: "Drive form",
                  question: "Choose the Mini Form answer",
                  options: [{ label: "Accepted", description: "Continue the run" }],
                  multiple: false,
                },
              ],
            },
          }),
          Llm.finish("tool-calls"),
        )
        yield* llm.queue(Llm.text("drive mini form complete"))
        yield* Effect.promise(() => tmux(["send-keys", "-t", session, "-l", "exercise the form"]))
        yield* Effect.promise(() => tmux(["send-keys", "-H", "-t", session, "0d"]))
        yield* Effect.promise(() => waitForPane(session, "Choose the Mini Form answer", 20_000))
        yield* Effect.promise(() => tmux(["send-keys", "-H", "-t", session, "0d"]))
        yield* Effect.promise(() => waitForPane(session, "drive mini form complete", 20_000))

        yield* llm.queue(
          Llm.toolCall({
            index: 0,
            id: "mini-slow-shell",
            name: "shell",
            input: { command: "sleep 10" },
          }),
          Llm.finish("tool-calls"),
        )
        yield* Effect.promise(() => tmux(["send-keys", "-t", session, "-l", "interrupt this turn"]))
        yield* Effect.sleep(100)
        yield* Effect.promise(() => tmux(["send-keys", "-H", "-t", session, "0d"]))
        yield* Effect.promise(() => waitForPane(session, "$ sleep 10"))
        yield* Effect.promise(() => tmux(["send-keys", "-t", session, "Escape"]))
        const armed = yield* Effect.promise(() => waitForPane(session, "esc again"))
        yield* Effect.promise(() => Bun.write(path.join(snapshots, "04-interrupt-armed.txt"), armed))
        yield* Effect.promise(() => tmux(["send-keys", "-t", session, "Escape"]))
        const interrupted = yield* Effect.promise(() => waitForPane(session, "Step interrupted", 10_000))
        yield* Effect.promise(() => Bun.write(path.join(snapshots, "05-interrupted.txt"), interrupted))

        yield* Effect.promise(async () => {
          if (!(await paneAlive(session))) throw new Error("Mini exited while interrupting an active turn")
        })
        yield* Effect.promise(() => tmux(["send-keys", "-t", session, "C-c"]))
        yield* Effect.promise(() => waitForPane(session, "EXIT  Press ctrl+"))
        yield* Effect.promise(() => tmux(["send-keys", "-t", session, "C-c"]))
        yield* Effect.promise(() => waitForDeadPane(session))
        const status = yield* Effect.promise(() => paneDeadStatus(session))
        if (status !== 0) throw new Error(`Mini exited with status ${status}`)
        const exited = yield* Effect.promise(() => capturePane(session))
        if (!exited.includes("Continue") || !exited.includes("opencode mini -s"))
          throw new Error("Mini exit splash was not rendered before teardown")
        yield* Effect.promise(() => Bun.write(path.join(snapshots, "06-exit-teardown.txt"), exited))

        yield* Effect.promise(() => tmux(["clear-history", "-t", session]))
        yield* Effect.promise(() =>
          tmux([
            "respawn-pane",
            "-k",
            "-t",
            session,
            "--",
            ...mini(explicitDirectory, "simulation/gpt-sim-model"),
          ]),
        )
        const explicitModel = yield* Effect.promise(() => waitForPane(session, "Simulated Model", 15_000))
        yield* Effect.promise(() => Bun.write(path.join(snapshots, "07-explicit-model.txt"), explicitModel))
        yield* Effect.promise(() => tmux(["send-keys", "-t", session, "C-c"]))
        yield* Effect.promise(() => waitForPane(session, "EXIT  Press ctrl+"))
        yield* Effect.promise(() => tmux(["send-keys", "-t", session, "C-c"]))
        yield* Effect.promise(() => waitForDeadPane(session))
        if ((yield* Effect.promise(() => paneDeadStatus(session))) !== 0)
          throw new Error("Explicit-model Mini did not exit cleanly")

        yield* Effect.promise(async () => {
          for (const failure of [
            {
              args: ["--model", "simulation/definitely-missing"],
              capture: "08-unavailable-model.txt",
              expected: "Model unavailable: simulation/definitely-missing",
            },
            {
              args: ["--agent", "definitely-missing"],
              capture: "09-unavailable-agent.txt",
              expected: 'Agent not found: "definitely-missing"',
            },
          ]) {
            const child = Bun.spawn(
              [
                process.execPath,
                path.join(root, "packages/cli/src/index.ts"),
                "run",
                "--server",
                registration.url,
                ...failure.args,
                "optimistic selection check",
              ],
              {
                cwd: path.join(root, "packages/cli"),
                env: {
                  ...process.env,
                  PWD: path.join(artifacts, "files"),
                  OPENCODE_PASSWORD: registration.password,
                  OPENCODE_CONFIG_DIR: path.join(artifacts, "files/.opencode"),
                  OPENCODE_DISABLE_AUTOUPDATE: "1",
                },
                stdin: "ignore",
                stdout: "pipe",
                stderr: "pipe",
              },
            )
            const [exitCode, stdout, stderr] = await Promise.all([
              child.exited,
              new Response(child.stdout).text(),
              new Response(child.stderr).text(),
            ])
            await Bun.write(path.join(snapshots, failure.capture), stdout + stderr)
            if (exitCode !== 1) throw new Error(`${failure.expected} run exited with status ${exitCode}`)
            if (!stderr.includes(failure.expected))
              throw new Error(`Selection failure was not diagnosed by execution: ${stderr}`)
          }
        })
      })

      yield* journey.pipe(Effect.ensuring(Effect.promise(() => tmux(["kill-session", "-t", session], true))))
    }),
})

/** @param {string[]} args */
async function tmux(args, allowFailure = false) {
  const child = Bun.spawn(["tmux", ...args], { stdout: "pipe", stderr: "pipe" })
  let timedOut = false
  const timeout = setTimeout(() => {
    timedOut = true
    child.kill("SIGKILL")
  }, 5_000)
  const [status, stdout, stderr] = await Promise.all([
    child.exited,
    new Response(child.stdout).text(),
    new Response(child.stderr).text(),
  ])
  clearTimeout(timeout)
  if (timedOut) throw new Error(`tmux ${args[0]} timed out`)
  if (status !== 0 && !allowFailure) throw new Error(`tmux ${args[0]} failed: ${stderr || stdout}`)
  return stdout
}

/** @param {string} session */
function capturePane(session) {
  return tmux(["capture-pane", "-p", "-t", session, "-S", "-"])
}

/** @param {string} session */
function captureVisiblePane(session) {
  return tmux(["capture-pane", "-p", "-t", session])
}

/** @param {string} session @param {string} text @param {number} [timeout] */
async function waitForVisiblePane(session, text, timeout = 5_000) {
  const deadline = Date.now() + timeout
  let last = ""
  while (Date.now() < deadline) {
    last = await captureVisiblePane(session)
    if (last.includes(text)) return last
    if (!(await paneAlive(session))) throw new Error(`Mini exited before rendering ${JSON.stringify(text)}:\n${last}`)
    await Bun.sleep(50)
  }
  throw new Error(`Timed out waiting for visible ${JSON.stringify(text)}:\n${last}`)
}

/** @param {string} session */
async function paneAlive(session) {
  return (await tmux(["display-message", "-p", "-t", session, "#{pane_dead}"], true)).trim() === "0"
}

/** @param {string} session */
async function paneDeadStatus(session) {
  return Number((await tmux(["display-message", "-p", "-t", session, "#{pane_dead_status}"])).trim())
}

/**
 * @param {string} session
 * @param {string} text
 * @param {number} [timeout]
 * @param {(() => Promise<void>) | undefined} [trigger]
 */
async function waitForPane(session, text, timeout = 5_000, trigger) {
  const deadline = Date.now() + timeout
  let last = ""
  while (Date.now() < deadline) {
    await trigger?.()
    last = await capturePane(session)
    if (last.includes(text)) return last
    if (!(await paneAlive(session))) throw new Error(`Mini exited before rendering ${JSON.stringify(text)}:\n${last}`)
    await Bun.sleep(50)
  }
  throw new Error(`Timed out waiting for ${JSON.stringify(text)}:\n${last}`)
}

/** @param {string} session */
async function waitForDeadPane(session) {
  for (let attempt = 0; attempt < 100; attempt++) {
    if (!(await paneAlive(session))) return
    await Bun.sleep(50)
  }
  throw new Error("Mini did not tear down after the exit sequence")
}

/**
 * @param {string} file
 * @param {(value: string) => boolean} accept
 */
async function waitForFile(file, accept) {
  let value = ""
  for (let attempt = 0; attempt < 100; attempt++) {
    value = await Bun.file(file)
      .text()
      .catch(() => "")
    if (accept(value)) return value
    await Bun.sleep(50)
  }
  throw new Error("resize did not replay committed transcript output")
}

/** @param {string} artifacts */
async function configureServicePort(artifacts) {
  const probe = Bun.serve({ hostname: "127.0.0.1", port: 0, fetch: () => new Response() })
  const port = probe.port
  await probe.stop(true)
  if (!port) throw new Error("Failed to allocate a Drive service port")
  const file = path.join(artifacts, "files/.opencode/service-local.json")
  await mkdir(path.dirname(file), { recursive: true })
  await Bun.write(file, JSON.stringify({ port }))
}

/** @param {string} artifacts */
async function serviceRegistration(artifacts) {
  const directory = path.join(artifacts, "home/.local/state/opencode")
  for (let attempt = 0; attempt < 200; attempt++) {
    for (const name of ["service-local.json", "service.json"]) {
      const value = await Bun.file(path.join(directory, name))
        .json()
        .catch(() => undefined)
      if (isRegistration(value)) return value
    }
    await Bun.sleep(50)
  }
  throw new Error("Drive service registration was not written")
}

/** @param {unknown} value */
function isRegistration(value) {
  return (
    typeof value === "object" &&
    value !== null &&
    "url" in value &&
    typeof value.url === "string" &&
    "password" in value &&
    typeof value.password === "string"
  )
}