import type { Locator, Page } from "@playwright/test"
import { test, expect } from "../fixtures"
import { openSidebar, resolveSlug, setWorkspacesEnabled, waitSession, waitSlug } from "../actions"
import {
  promptAgentSelector,
  promptModelSelector,
  promptVariantSelector,
  workspaceItemSelector,
  workspaceNewSessionSelector,
} from "../selectors"
import { createSdk, sessionPath } from "../utils"

type Footer = {
  agent: string
  model: string
  variant: string
}

type Probe = {
  dir?: string
  sessionID?: string
  agent?: string
  model?: { providerID: string; modelID: string; name?: string }
  variant?: string | null
  pick?: {
    agent?: string
    model?: { providerID: string; modelID: string }
    variant?: string | null
  }
  variants?: string[]
  models?: Array<{ providerID: string; modelID: string; name: string }>
  agents?: Array<{ name: string }>
}

const escape = (value: string) => value.replace(/[.*+?^${}()|[\]\\]/g, "\\$&")

const text = async (locator: Locator) => ((await locator.textContent()) ?? "").trim()

const modelKey = (state: Probe | null) => (state?.model ? `${state.model.providerID}:${state.model.modelID}` : null)

async function probe(page: Page): Promise<Probe | null> {
  return page.evaluate(() => {
    const win = window as Window & {
      __opencode_e2e?: {
        model?: {
          current?: Probe
        }
      }
    }
    return win.__opencode_e2e?.model?.current ?? null
  })
}

async function currentModel(page: Page) {
  await expect.poll(() => probe(page).then(modelKey), { timeout: 30_000 }).not.toBe(null)
  const value = await probe(page).then(modelKey)
  if (!value) throw new Error("Failed to resolve current model key")
  return value
}

async function waitControl(page: Page, key: "setAgent" | "setModel" | "setVariant") {
  await expect
    .poll(
      () =>
        page.evaluate((key) => {
          const win = window as Window & {
            __opencode_e2e?: {
              model?: {
                controls?: Record<string, unknown>
              }
            }
          }
          return !!win.__opencode_e2e?.model?.controls?.[key]
        }, key),
      { timeout: 30_000 },
    )
    .toBe(true)
}

async function pickAgent(page: Page, value: string) {
  await waitControl(page, "setAgent")
  await page.evaluate((value) => {
    const win = window as Window & {
      __opencode_e2e?: {
        model?: {
          controls?: {
            setAgent?: (value: string | undefined) => void
          }
        }
      }
    }
    const fn = win.__opencode_e2e?.model?.controls?.setAgent
    if (!fn) throw new Error("Model e2e agent control is not enabled")
    fn(value)
  }, value)
}

async function pickModel(page: Page, value: { providerID: string; modelID: string }) {
  await waitControl(page, "setModel")
  await page.evaluate((value) => {
    const win = window as Window & {
      __opencode_e2e?: {
        model?: {
          controls?: {
            setModel?: (value: { providerID: string; modelID: string } | undefined) => void
          }
        }
      }
    }
    const fn = win.__opencode_e2e?.model?.controls?.setModel
    if (!fn) throw new Error("Model e2e model control is not enabled")
    fn(value)
  }, value)
}

async function pickVariant(page: Page, value: string) {
  await waitControl(page, "setVariant")
  await page.evaluate((value) => {
    const win = window as Window & {
      __opencode_e2e?: {
        model?: {
          controls?: {
            setVariant?: (value: string | undefined) => void
          }
        }
      }
    }
    const fn = win.__opencode_e2e?.model?.controls?.setVariant
    if (!fn) throw new Error("Model e2e variant control is not enabled")
    fn(value)
  }, value)
}

async function read(page: Page): Promise<Footer> {
  return {
    agent: await text(page.locator(`${promptAgentSelector} [data-slot="select-select-trigger-value"]`).first()),
    model: await text(page.locator(`${promptModelSelector} [data-action="prompt-model"] span`).first()),
    variant: await text(page.locator(`${promptVariantSelector} [data-slot="select-select-trigger-value"]`).first()),
  }
}

async function waitFooter(page: Page, expected: Partial<Footer>) {
  let hit: Footer | null = null
  await expect
    .poll(
      async () => {
        const state = await read(page)
        const ok = Object.entries(expected).every(([key, value]) => state[key as keyof Footer] === value)
        if (ok) hit = state
        return ok
      },
      { timeout: 30_000 },
    )
    .toBe(true)
  if (!hit) throw new Error("Failed to resolve prompt footer state")
  return hit
}

async function waitModel(page: Page, value: string) {
  await expect.poll(() => probe(page).then(modelKey), { timeout: 30_000 }).toBe(value)
}

async function choose(page: Page, root: string, value: string) {
  const select = page.locator(root)
  await expect(select).toBeVisible()
  await pickAgent(page, value)
}

async function variantCount(page: Page) {
  return (await probe(page))?.variants?.length ?? 0
}

async function agents(page: Page) {
  return ((await probe(page))?.agents ?? []).map((item) => item.name).filter(Boolean)
}

async function ensureVariant(page: Page, directory: string): Promise<Footer> {
  const current = await read(page)
  if ((await variantCount(page)) >= 2) return current

  const cfg = await createSdk(directory)
    .config.get()
    .then((x) => x.data)
  const visible = new Set(await agents(page))
  const entry = Object.entries(cfg?.agent ?? {}).find((item) => {
    const value = item[1]
    return !!value && typeof value === "object" && "variant" in value && "model" in value && visible.has(item[0])
  })
  const name = entry?.[0]
  test.skip(!name, "no agent with alternate variants available")
  if (!name) return current

  await choose(page, promptAgentSelector, name)
  await expect.poll(() => variantCount(page), { timeout: 30_000 }).toBeGreaterThanOrEqual(2)
  return waitFooter(page, { agent: name })
}

async function chooseDifferentVariant(page: Page): Promise<Footer> {
  const current = await read(page)
  const next = (await probe(page))?.variants?.find((item) => item !== current.variant)
  if (!next) throw new Error("Current model has no alternate variant to select")

  await pickVariant(page, next)
  return waitFooter(page, { agent: current.agent, model: current.model, variant: next })
}

async function chooseOtherModel(page: Page, skip: string[] = []): Promise<Footer> {
  const current = await currentModel(page)
  const next = (await probe(page))?.models?.find((item) => {
    const key = `${item.providerID}:${item.modelID}`
    return key !== current && !skip.includes(key)
  })
  if (!next) throw new Error("Failed to choose a different model")
  await pickModel(page, { providerID: next.providerID, modelID: next.modelID })
  await expect.poll(async () => (await read(page)).model, { timeout: 30_000 }).toBe(next.name)
  return read(page)
}

async function goto(page: Page, directory: string, sessionID?: string) {
  await page.goto(sessionPath(directory, sessionID))
  await waitSession(page, { directory, sessionID })
}

async function submit(project: Parameters<typeof test>[0]["project"], value: string) {
  return project.prompt(value)
}

async function createWorkspace(page: Page, root: string, seen: string[]) {
  await openSidebar(page)
  await page.getByRole("button", { name: "New workspace" }).first().click()

  const next = await resolveSlug(await waitSlug(page, [root, ...seen]))
  await waitSession(page, { directory: next.directory })
  return next
}

async function waitWorkspace(page: Page, slug: string) {
  await openSidebar(page)
  await expect
    .poll(
      async () => {
        const item = page.locator(workspaceItemSelector(slug)).first()
        try {
          await item.hover({ timeout: 500 })
          return true
        } catch {
          return false
        }
      },
      { timeout: 60_000 },
    )
    .toBe(true)
}

async function newWorkspaceSession(page: Page, slug: string) {
  await waitWorkspace(page, slug)
  const item = page.locator(workspaceItemSelector(slug)).first()
  await item.hover()

  const button = page.locator(workspaceNewSessionSelector(slug)).first()
  await expect(button).toBeVisible()
  await button.click({ force: true })

  const next = await resolveSlug(await waitSlug(page))
  return waitSession(page, { directory: next.directory }).then((item) => item.directory)
}

test("session model restore per session without leaking into new sessions", async ({ page, project }) => {
  await page.setViewportSize({ width: 1440, height: 900 })

  await project.open()
  await project.gotoSession()

  const firstState = await chooseOtherModel(page)
  const firstKey = await currentModel(page)
  const first = await submit(project, `session variant ${Date.now()}`)

  await page.reload()
  await waitSession(page, { directory: project.directory, sessionID: first })
  await waitFooter(page, firstState)

  await project.gotoSession()
  const fresh = await read(page)
  expect(fresh.model).not.toBe(firstState.model)

  const secondState = await chooseOtherModel(page, [firstKey])
  const second = await submit(project, `session model ${Date.now()}`)

  await goto(page, project.directory, first)
  await waitFooter(page, firstState)

  await goto(page, project.directory, second)
  await waitFooter(page, secondState)

  await project.gotoSession()
  await page.reload()
  await waitSession(page, { directory: project.directory })
  await waitFooter(page, fresh)
})

test("session model restore across workspaces", async ({ page, project }) => {
  await page.setViewportSize({ width: 1440, height: 900 })

  await project.open()
  const root = project.directory
  await project.gotoSession()

  const firstState = await chooseOtherModel(page)
  const firstKey = await currentModel(page)
  const first = await submit(project, `root session ${Date.now()}`)

  await openSidebar(page)
  await setWorkspacesEnabled(page, project.slug, true)

  const one = await createWorkspace(page, project.slug, [])
  const oneDir = await newWorkspaceSession(page, one.slug)
  project.trackDirectory(oneDir)

  const secondState = await chooseOtherModel(page, [firstKey])
  const secondKey = await currentModel(page)
  const second = await submit(project, `workspace one ${Date.now()}`)

  const two = await createWorkspace(page, project.slug, [one.slug])
  const twoDir = await newWorkspaceSession(page, two.slug)
  project.trackDirectory(twoDir)

  const thirdState = await chooseOtherModel(page, [firstKey, secondKey])
  const third = await submit(project, `workspace two ${Date.now()}`)

  await goto(page, root, first)
  await waitFooter(page, firstState)

  await goto(page, oneDir, second)
  await waitFooter(page, secondState)

  await goto(page, twoDir, third)
  await waitFooter(page, thirdState)

  await goto(page, root, first)
  await waitFooter(page, firstState)
})

test("variant preserved when switching agent modes", async ({ page, project }) => {
  await page.setViewportSize({ width: 1440, height: 900 })

  await project.open()
  await project.gotoSession()

  await ensureVariant(page, project.directory)
  const updated = await chooseDifferentVariant(page)

  const available = await agents(page)
  const other = available.find((name) => name !== updated.agent)
  test.skip(!other, "only one agent available")
  if (!other) return

  await choose(page, promptAgentSelector, other)
  await waitFooter(page, { agent: other, variant: updated.variant })

  await choose(page, promptAgentSelector, updated.agent)
  await waitFooter(page, { agent: updated.agent, variant: updated.variant })
})