import type { BrowserFormField } from "./client-actions-core.js";
import {
  ensurePageState,
  getPageForTargetId,
  refLocator,
} from "./pw-session.js";
import {
  normalizeTimeoutMs,
  requireRef,
  toAIFriendlyError,
} from "./pw-tools-core.shared.js";

export async function highlightViaPlaywright(opts: {
  cdpUrl: string;
  targetId?: string;
  ref: string;
}): Promise<void> {
  const page = await getPageForTargetId(opts);
  ensurePageState(page);
  const ref = requireRef(opts.ref);
  try {
    await refLocator(page, ref).highlight();
  } catch (err) {
    throw toAIFriendlyError(err, ref);
  }
}

export async function clickViaPlaywright(opts: {
  cdpUrl: string;
  targetId?: string;
  ref: string;
  doubleClick?: boolean;
  button?: "left" | "right" | "middle";
  modifiers?: Array<"Alt" | "Control" | "ControlOrMeta" | "Meta" | "Shift">;
  timeoutMs?: number;
}): Promise<void> {
  const page = await getPageForTargetId({
    cdpUrl: opts.cdpUrl,
    targetId: opts.targetId,
  });
  ensurePageState(page);
  const ref = requireRef(opts.ref);
  const locator = refLocator(page, ref);
  const timeout = Math.max(
    500,
    Math.min(60_000, Math.floor(opts.timeoutMs ?? 8000)),
  );
  try {
    if (opts.doubleClick) {
      await locator.dblclick({
        timeout,
        button: opts.button,
        modifiers: opts.modifiers,
      });
    } else {
      await locator.click({
        timeout,
        button: opts.button,
        modifiers: opts.modifiers,
      });
    }
  } catch (err) {
    throw toAIFriendlyError(err, ref);
  }
}

export async function hoverViaPlaywright(opts: {
  cdpUrl: string;
  targetId?: string;
  ref: string;
  timeoutMs?: number;
}): Promise<void> {
  const ref = requireRef(opts.ref);
  const page = await getPageForTargetId(opts);
  ensurePageState(page);
  try {
    await refLocator(page, ref).hover({
      timeout: Math.max(500, Math.min(60_000, opts.timeoutMs ?? 8000)),
    });
  } catch (err) {
    throw toAIFriendlyError(err, ref);
  }
}

export async function dragViaPlaywright(opts: {
  cdpUrl: string;
  targetId?: string;
  startRef: string;
  endRef: string;
  timeoutMs?: number;
}): Promise<void> {
  const startRef = requireRef(opts.startRef);
  const endRef = requireRef(opts.endRef);
  if (!startRef || !endRef) throw new Error("startRef and endRef are required");
  const page = await getPageForTargetId(opts);
  ensurePageState(page);
  try {
    await refLocator(page, startRef).dragTo(refLocator(page, endRef), {
      timeout: Math.max(500, Math.min(60_000, opts.timeoutMs ?? 8000)),
    });
  } catch (err) {
    throw toAIFriendlyError(err, `${startRef} -> ${endRef}`);
  }
}

export async function selectOptionViaPlaywright(opts: {
  cdpUrl: string;
  targetId?: string;
  ref: string;
  values: string[];
  timeoutMs?: number;
}): Promise<void> {
  const ref = requireRef(opts.ref);
  if (!opts.values?.length) throw new Error("values are required");
  const page = await getPageForTargetId(opts);
  ensurePageState(page);
  try {
    await refLocator(page, ref).selectOption(opts.values, {
      timeout: Math.max(500, Math.min(60_000, opts.timeoutMs ?? 8000)),
    });
  } catch (err) {
    throw toAIFriendlyError(err, ref);
  }
}

export async function pressKeyViaPlaywright(opts: {
  cdpUrl: string;
  targetId?: string;
  key: string;
  delayMs?: number;
}): Promise<void> {
  const key = String(opts.key ?? "").trim();
  if (!key) throw new Error("key is required");
  const page = await getPageForTargetId(opts);
  ensurePageState(page);
  await page.keyboard.press(key, {
    delay: Math.max(0, Math.floor(opts.delayMs ?? 0)),
  });
}

export async function typeViaPlaywright(opts: {
  cdpUrl: string;
  targetId?: string;
  ref: string;
  text: string;
  submit?: boolean;
  slowly?: boolean;
  timeoutMs?: number;
}): Promise<void> {
  const text = String(opts.text ?? "");
  const page = await getPageForTargetId(opts);
  ensurePageState(page);
  const ref = requireRef(opts.ref);
  const locator = refLocator(page, ref);
  const timeout = Math.max(500, Math.min(60_000, opts.timeoutMs ?? 8000));
  try {
    if (opts.slowly) {
      await locator.click({ timeout });
      await locator.type(text, { timeout, delay: 75 });
    } else {
      await locator.fill(text, { timeout });
    }
    if (opts.submit) {
      await locator.press("Enter", { timeout });
    }
  } catch (err) {
    throw toAIFriendlyError(err, ref);
  }
}

export async function fillFormViaPlaywright(opts: {
  cdpUrl: string;
  targetId?: string;
  fields: BrowserFormField[];
  timeoutMs?: number;
}): Promise<void> {
  const page = await getPageForTargetId(opts);
  ensurePageState(page);
  const timeout = Math.max(500, Math.min(60_000, opts.timeoutMs ?? 8000));
  for (const field of opts.fields) {
    const ref = field.ref.trim();
    const type = field.type.trim();
    const rawValue = field.value;
    const value =
      typeof rawValue === "string"
        ? rawValue
        : typeof rawValue === "number" || typeof rawValue === "boolean"
          ? String(rawValue)
          : "";
    if (!ref || !type) continue;
    const locator = refLocator(page, ref);
    if (type === "checkbox" || type === "radio") {
      const checked =
        rawValue === true ||
        rawValue === 1 ||
        rawValue === "1" ||
        rawValue === "true";
      try {
        await locator.setChecked(checked, { timeout });
      } catch (err) {
        throw toAIFriendlyError(err, ref);
      }
      continue;
    }
    try {
      await locator.fill(value, { timeout });
    } catch (err) {
      throw toAIFriendlyError(err, ref);
    }
  }
}

export async function evaluateViaPlaywright(opts: {
  cdpUrl: string;
  targetId?: string;
  fn: string;
  ref?: string;
}): Promise<unknown> {
  const fnText = String(opts.fn ?? "").trim();
  if (!fnText) throw new Error("function is required");
  const page = await getPageForTargetId(opts);
  ensurePageState(page);
  if (opts.ref) {
    const locator = refLocator(page, opts.ref);
    // Use Function constructor at runtime to avoid esbuild adding __name helper
    // which doesn't exist in the browser context
    // eslint-disable-next-line @typescript-eslint/no-implied-eval -- required for browser-context eval
    const elementEvaluator = new Function(
      "el",
      "fnBody",
      `
      "use strict";
      try {
        var candidate = eval("(" + fnBody + ")");
        return typeof candidate === "function" ? candidate(el) : candidate;
      } catch (err) {
        throw new Error("Invalid evaluate function: " + (err && err.message ? err.message : String(err)));
      }
      `,
    ) as (el: Element, fnBody: string) => unknown;
    return await locator.evaluate(elementEvaluator, fnText);
  }
  // Use Function constructor at runtime to avoid esbuild adding __name helper
  // which doesn't exist in the browser context
  // eslint-disable-next-line @typescript-eslint/no-implied-eval -- required for browser-context eval
  const browserEvaluator = new Function(
    "fnBody",
    `
    "use strict";
    try {
      var candidate = eval("(" + fnBody + ")");
      return typeof candidate === "function" ? candidate() : candidate;
    } catch (err) {
      throw new Error("Invalid evaluate function: " + (err && err.message ? err.message : String(err)));
    }
    `,
  ) as (fnBody: string) => unknown;
  return await page.evaluate(browserEvaluator, fnText);
}

export async function scrollIntoViewViaPlaywright(opts: {
  cdpUrl: string;
  targetId?: string;
  ref: string;
  timeoutMs?: number;
}): Promise<void> {
  const page = await getPageForTargetId(opts);
  ensurePageState(page);
  const timeout = normalizeTimeoutMs(opts.timeoutMs, 20_000);

  const ref = requireRef(opts.ref);
  const locator = refLocator(page, ref);
  try {
    await locator.scrollIntoViewIfNeeded({ timeout });
  } catch (err) {
    throw toAIFriendlyError(err, ref);
  }
}

export async function waitForViaPlaywright(opts: {
  cdpUrl: string;
  targetId?: string;
  timeMs?: number;
  text?: string;
  textGone?: string;
  selector?: string;
  url?: string;
  loadState?: "load" | "domcontentloaded" | "networkidle";
  fn?: string;
  timeoutMs?: number;
}): Promise<void> {
  const page = await getPageForTargetId(opts);
  ensurePageState(page);
  const timeout = normalizeTimeoutMs(opts.timeoutMs, 20_000);

  if (typeof opts.timeMs === "number" && Number.isFinite(opts.timeMs)) {
    await page.waitForTimeout(Math.max(0, opts.timeMs));
  }
  if (opts.text) {
    await page.getByText(opts.text).first().waitFor({
      state: "visible",
      timeout,
    });
  }
  if (opts.textGone) {
    await page.getByText(opts.textGone).first().waitFor({
      state: "hidden",
      timeout,
    });
  }
  if (opts.selector) {
    const selector = String(opts.selector).trim();
    if (selector) {
      await page
        .locator(selector)
        .first()
        .waitFor({ state: "visible", timeout });
    }
  }
  if (opts.url) {
    const url = String(opts.url).trim();
    if (url) {
      await page.waitForURL(url, { timeout });
    }
  }
  if (opts.loadState) {
    await page.waitForLoadState(opts.loadState, { timeout });
  }
  if (opts.fn) {
    const fn = String(opts.fn).trim();
    if (fn) {
      await page.waitForFunction(fn, { timeout });
    }
  }
}

export async function takeScreenshotViaPlaywright(opts: {
  cdpUrl: string;
  targetId?: string;
  ref?: string;
  element?: string;
  fullPage?: boolean;
  type?: "png" | "jpeg";
}): Promise<{ buffer: Buffer }> {
  const page = await getPageForTargetId(opts);
  ensurePageState(page);
  const type = opts.type ?? "png";
  if (opts.ref) {
    if (opts.fullPage)
      throw new Error("fullPage is not supported for element screenshots");
    const locator = refLocator(page, opts.ref);
    const buffer = await locator.screenshot({ type });
    return { buffer };
  }
  if (opts.element) {
    if (opts.fullPage)
      throw new Error("fullPage is not supported for element screenshots");
    const locator = page.locator(opts.element).first();
    const buffer = await locator.screenshot({ type });
    return { buffer };
  }
  const buffer = await page.screenshot({
    type,
    fullPage: Boolean(opts.fullPage),
  });
  return { buffer };
}

export async function setInputFilesViaPlaywright(opts: {
  cdpUrl: string;
  targetId?: string;
  inputRef?: string;
  element?: string;
  paths: string[];
}): Promise<void> {
  const page = await getPageForTargetId(opts);
  ensurePageState(page);
  if (!opts.paths.length) throw new Error("paths are required");
  const inputRef =
    typeof opts.inputRef === "string" ? opts.inputRef.trim() : "";
  const element = typeof opts.element === "string" ? opts.element.trim() : "";
  if (inputRef && element) {
    throw new Error("inputRef and element are mutually exclusive");
  }
  if (!inputRef && !element) {
    throw new Error("inputRef or element is required");
  }

  const locator = inputRef
    ? refLocator(page, inputRef)
    : page.locator(element).first();

  try {
    await locator.setInputFiles(opts.paths);
  } catch (err) {
    throw toAIFriendlyError(err, inputRef || element);
  }
  try {
    const handle = await locator.elementHandle();
    if (handle) {
      await handle.evaluate((el) => {
        el.dispatchEvent(new Event("input", { bubbles: true }));
        el.dispatchEvent(new Event("change", { bubbles: true }));
      });
    }
  } catch {
    // Best-effort for sites that don't react to setInputFiles alone.
  }
}