"""
百度文心一言 https://wenxin.baidu.com/new-chat
"""
import os
import re
import time
import random
import tempfile
from PIL import Image
from playwright.sync_api import Page, TimeoutError as PWTimeout
import config

URL = "https://wenxin.baidu.com/"


def query(page: Page, question: str, brand_keywords: list = None, enable_screenshot: bool = True, output_dir: str = None) -> tuple[str, list]:
    page.goto(URL, wait_until="domcontentloaded", timeout=60000)
    try:
        page.wait_for_selector(
            "textarea, div[contenteditable='true']",
            timeout=20000, state="visible"
        )
    except PWTimeout:
        pass
    _random_wait(1500, 2000)

    editor = _find_editor(page)
    if not editor:
        raise RuntimeError("未找到输入框")

    editor.click()
    _random_wait(400, 700)
    _human_type(page, question)
    _random_wait(500, 800)

    _verify_and_send(page, editor, question)

    _random_wait(2000, 3000)

    _wait_for_answer(page)

    answer = _get_last_answer(page)

    # 根据配置决定是否截图
    if enable_screenshot:
        screenshot_path = _take_screenshot(page, question, brand_keywords, output_dir)
        if screenshot_path:
            print(f"    截图 -> {screenshot_path}")
    else:
        print("    跳过截图（禁用）")

    references = _get_references(page)

    return answer, references


# ── 内部工具 ────────────────────────────────────────────

def _random_wait(min_ms, max_ms):
    time.sleep(random.randint(min_ms, max_ms) / 1000)


def _human_type(page: Page, text: str):
    for char in text:
        page.keyboard.type(char)
        time.sleep(random.randint(30, 100) / 1000)


def _find_editor(page: Page):
    for sel in ["textarea", "div[contenteditable='true']", "[class*='input']", "[role='textbox']"]:
        loc = page.locator(sel).first
        try:
            if loc.is_visible(timeout=3000):
                return loc
        except PWTimeout:
            continue
    return None


def _verify_and_send(page: Page, editor, question: str):
    for attempt in range(3):
        try:
            content = editor.input_value(timeout=1000)
        except Exception:
            content = editor.inner_text(timeout=1000)

        if content.strip():
            break

        print(f"    输入框为空，重新输入(第{attempt+1}次)...")
        editor.click()
        _random_wait(300, 500)
        _human_type(page, question)
        _random_wait(400, 600)

    sent = False
    for sel in [
        "button[aria-label*='发送']",
        "button[type='submit']",
        "[class*='send']",
        "[class*='submit']",
    ]:
        btn = page.locator(sel).first
        try:
            if btn.is_visible(timeout=1500) and btn.is_enabled(timeout=1500):
                btn.click()
                sent = True
                break
        except PWTimeout:
            continue

    if not sent:
        editor.click()
        _random_wait(200, 300)
        page.keyboard.press("Enter")


def _wait_for_answer(page: Page):
    """等待文心回答完成：文字停止增长（连续 4 次 × 2 秒无变化）"""
    print("    等待文心回答", end="", flush=True)
    deadline = time.time() + config.ANSWER_TIMEOUT
    time.sleep(4)

    stable_count = 0
    last_len = -1

    while time.time() < deadline:
        current_text = _get_last_answer(page)
        current_len = len(current_text)

        if current_len > 50 and current_len == last_len:
            stable_count += 1
            print(".", end="", flush=True)
            if stable_count >= 4:
                print(" OK")
                break
        else:
            stable_count = 0
            if current_len > 0:
                print(f"({current_len})", end="", flush=True)

        last_len = current_len
        time.sleep(2)
    else:
        print(" 超时")

    time.sleep(2)


def _get_last_answer(page: Page) -> str:
    try:
        return page.evaluate("""() => {
            let best = null, bestLen = 0;
            for (const el of document.querySelectorAll('div, article, section')) {
                const r = el.getBoundingClientRect();
                if (r.left < 200 || r.width < 300) continue;
                if (el.children.length > 60) continue;
                const t = (el.innerText || '').trim();
                if (t.length > bestLen) { bestLen = t.length; best = el; }
            }
            return best ? best.innerText.trim() : '';
        }""") or ""
    except Exception:
        return ""


def _get_references(page: Page) -> list:
    """
    文心引用抓取：
    1. 点击「源」按钮（class: _c-reference-search_wv9xl_1 / _container_wv9xl_4）
    2. 等待右侧引用面板展开（class: _reference-search_m9abw_1）
    3. 逐条点击引用条目（class: _item_m9abw_26），捕获新标签页 URL
    """
    try:
        refs = []
        internal_domains = ['baidu.com', 'bdstatic.com', 'bcebos.com']

        # ── 1. 点击「源」按钮 ──────────────────────────────
        source_btn = None
        for sel in [
            "[class*='_c-reference-search_wv9xl']",
            "[class*='_container_wv9xl']",
        ]:
            try:
                locs = page.locator(sel).all()
                for loc in locs:
                    if loc.is_visible(timeout=1000):
                        source_btn = loc
                        break
            except Exception:
                pass
            if source_btn:
                break

        if not source_btn:
            print("    引用参考: 未找到「源」按钮")
            return []

        source_btn.click()
        time.sleep(2)  # 等待右侧面板展开

        # ── 2. 等待引用面板出现 ────────────────────────────
        try:
            page.wait_for_selector(
                "[class*='_reference-search_m9abw']",
                timeout=5000, state="visible"
            )
        except Exception:
            pass

        # ── 3. 读取所有引用条目 ────────────────────────────
        items = page.locator("[class*='_item_m9abw']").all()
        if not items:
            print("    引用参考: 面板已展开但未找到条目")
            return []

        print(f"    引用参考: 发现 {len(items)} 条，开始抓取...")

        for item in items[:50]:  # 最多尝试 50 条
            try:
                title = item.inner_text(timeout=1000).strip().split('\n')[0]
                if not title or len(title) < 3:
                    continue

                # 点击条目，等待新标签页
                with page.context.expect_page(timeout=6000) as new_page_info:
                    item.click()

                new_page = new_page_info.value
                try:
                    new_page.wait_for_load_state("domcontentloaded", timeout=8000)
                except Exception:
                    pass
                new_url = new_page.url
                new_page.close()
                page.bring_to_front()
                time.sleep(0.3)

                if (new_url and new_url.startswith('http')
                        and not any(d in new_url for d in internal_domains)):
                    refs.append({"title": title[:120], "url": new_url, "content": ""})
                    print(f"    OK [{len(refs)}] {title[:40]} -> {new_url[:70]}")
                    if len(refs) >= 30: # 抓取到 30 篇有效的就停止，避免开太多标签页
                        break

            except Exception as e:
                print(f"    跳过: {str(e)[:60]}")
                continue

        # ── 4. 去重 ────────────────────────────────────────
        seen, unique = set(), []
        for r in refs:
            if r["url"] not in seen:
                seen.add(r["url"])
                unique.append(r)

        print(f"    引用参考: 共 {len(unique)} 篇")
        return unique

    except Exception as e:
        print(f"    引用参考抓取失败: {e}")
        return []


def _take_screenshot(page: Page, question: str, brand_keywords: list = None, output_dir: str = None) -> str:
    """
    长截图：GoFullPage 同款算法。
    用 JS 给滚动容器打标记，按固定步长精确设置 scrollTop，
    每步截图后按坐标直接拼接，零图像匹配，零重复。
    """
    try:
        from utils import get_timestamp_dir, find_keyword_positions, draw_marks
        timestamp_dir = get_timestamp_dir()
        # 使用传入的 output_dir，如果没有则使用默认配置
        base_dir = output_dir if output_dir else config.OUTPUT_DIR
        shot_dir = os.path.join(base_dir, timestamp_dir, "screenshots")
        os.makedirs(shot_dir, exist_ok=True)
        safe_name = re.sub(r'[\\/:*?"<>|]', "_", question).strip(".")[:80]
        shot_path = os.path.join(shot_dir, f"{safe_name}.png")

        # ── 1. 截图区域 ───────────────────────────────────
        clip_x = page.evaluate("""() => {
            let leftBound = 200;
            Array.from(document.querySelectorAll('*')).forEach(el => {
                const r  = el.getBoundingClientRect();
                const cs = window.getComputedStyle(el);
                if (r.left < 10 && r.width > 80 && r.width < 400
                        && r.height > 400 && cs.display !== 'none') {
                    leftBound = Math.max(leftBound, Math.round(r.right) + 2);
                }
            });
            return leftBound;
        }""")
        vp     = page.viewport_size
        clip_w = vp["width"] - clip_x

        # 顶部边界：检测 fixed/sticky header，避免每帧都截到 header 导致拼接时重复出现
        clip_y = page.evaluate("""() => {
            let bottom = 0;
            document.querySelectorAll('*').forEach(el => {
                const cs = window.getComputedStyle(el);
                const r  = el.getBoundingClientRect();
                if ((cs.position === 'fixed' || cs.position === 'sticky')
                        && r.top < 20 && r.width > 200 && r.height > 0
                        && r.height < 120 && cs.display !== 'none') {
                    bottom = Math.max(bottom, Math.round(r.bottom));
                }
            });
            return bottom;
        }""")

        # 底部边界：排除输入框和追问建议框
        input_top = page.evaluate("""() => {
            const vh = window.innerHeight;
            let top = vh;
            document.querySelectorAll(
                'textarea, [class*="input"], [class*="composer"], [class*="suggest"], [class*="footer"]'
            ).forEach(el => {
                const r  = el.getBoundingClientRect();
                const cs = window.getComputedStyle(el);
                if (r.bottom > vh * 0.4 && r.width > 100 && cs.display !== 'none') {
                    top = Math.min(top, r.top);
                }
            });
            return Math.round(top);
        }""")
        clip_h = min(input_top - 4, vp["height"] - 150) - clip_y

        # ── 2. 找滚动容器，打标记，获取总高度 ────────────
        info = page.evaluate("""() => {
            // 找 scrollHeight 最大的可滚动容器
            let best = null, bestH = 0;
            document.querySelectorAll('*').forEach(el => {
                const cs = window.getComputedStyle(el);
                const r  = el.getBoundingClientRect();
                if ((cs.overflowY === 'auto' || cs.overflowY === 'scroll')
                        && el.scrollHeight > el.clientHeight + 50
                        && r.width > 300 && r.height > 200
                        && el.scrollHeight > bestH) {
                    bestH = el.scrollHeight;
                    best  = el;
                }
            });
            if (best) {
                best.setAttribute('data-gofullpage-target', '1');
                best.scrollTop = 0;
                return {
                    found: true,
                    scrollHeight: best.scrollHeight,
                    clientHeight: best.clientHeight,
                };
            }
            window.scrollTo(0, 0);
            return {
                found: false,
                scrollHeight: document.documentElement.scrollHeight,
                clientHeight: window.innerHeight,
            };
        }""")
        time.sleep(0.8)

        total_scroll = info["scrollHeight"]
        client_h     = info["clientHeight"]
        found        = info["found"]

        # ── 3. 查找关键词位置 ───────────────────────────
        keyword_marks = []
        if brand_keywords:
            keyword_marks = find_keyword_positions(page, brand_keywords)
            if keyword_marks:
                print(f"    发现 {len(keyword_marks)} 处品牌词曝光")

        # 步长 = clip_h（每次滚动一个视口高度）
        step = clip_h

        def _scroll_to(pos: int):
            if found:
                page.evaluate(f"""() => {{
                    const el = document.querySelector('[data-gofullpage-target="1"]');
                    if (el) el.scrollTop = {pos};
                }}""")
            else:
                page.evaluate(f"window.scrollTo(0, {pos})")

        def _get_scroll() -> int:
            if found:
                return page.evaluate("""() => {
                    const el = document.querySelector('[data-gofullpage-target="1"]');
                    return el ? Math.round(el.scrollTop) : 0;
                }""")
            return page.evaluate("() => Math.round(window.scrollY)")

        def _snap() -> Image.Image:
            tmp = tempfile.mktemp(suffix=".png")
            page.screenshot(path=tmp, clip={
                "x": clip_x, "y": clip_y,
                "width": clip_w, "height": clip_h,
            })
            img = Image.open(tmp).copy()
            os.unlink(tmp)
            return img

        # ── 3. 按坐标步进截图（GoFullPage 同款）─────────
        # 每帧记录截图时的实际 scrollTop
        frames: list[tuple[int, Image.Image]] = []  # (actual_scroll, img)
        pos = 0

        while True:
            _scroll_to(pos)
            time.sleep(0.4)
            actual = _get_scroll()
            img    = _snap()
            frames.append((actual, img))
            print(f"(s={actual})", end="", flush=True)

            # 到底判断：实际 scrollTop + clientHeight >= scrollHeight
            if actual + client_h >= total_scroll - 2:
                break
            if pos + step > total_scroll:
                break
            pos += step

        # ── 4. 按坐标直接拼接（无图像匹配）─────────────
        if not frames:
            print("    截图: 未获取到帧")
            return ""

        if len(frames) == 1:
            frames[0][1].save(shot_path, optimize=True, quality=95)
            print(f"\n    截图: 1 帧，总高 {frames[0][1].height}px")
            return shot_path

        # 计算画布总高度：
        # 第一帧完整高度 + 后续每帧的新增高度（= 本帧 scrollTop - 上一帧 scrollTop）
        total_h = frames[0][1].height
        for i in range(1, len(frames)):
            new_px = frames[i][0] - frames[i-1][0]  # 本次实际滚动了多少 px
            new_px = max(new_px, 1)
            new_px = min(new_px, frames[i][1].height)
            total_h += new_px

        canvas = Image.new("RGB", (frames[0][1].width, total_h), (255, 255, 255))

        # 第一帧完整粘贴
        canvas.paste(frames[0][1], (0, 0))
        y_offset = frames[0][1].height

        for i in range(1, len(frames)):
            new_px = frames[i][0] - frames[i-1][0]
            new_px = max(new_px, 1)
            new_px = min(new_px, frames[i][1].height)
            # 从当前帧顶部跳过与上一帧重叠的部分，取剩余新内容
            img_h   = frames[i][1].height
            overlap = img_h - new_px  # 与上一帧重叠的像素数
            cropped = frames[i][1].crop((0, overlap, frames[i][1].width, img_h))
            canvas.paste(cropped, (0, y_offset))
            y_offset += cropped.height

        # ── 5. 绘制品牌词红框 ───────────────────────────
        if keyword_marks:
            canvas = draw_marks(canvas, keyword_marks, clip_x, clip_y)

        canvas.save(shot_path, optimize=True, quality=95)
        print(f"\n    截图: {len(frames)} 帧拼接，总高 {total_h}px")
        return shot_path

    except Exception as e:
        print(f"    截图失败: {e}")
        return ""
