import logging
import math
import os
import random
import re
import sys
import threading
from collections import Counter, defaultdict
from copy import deepcopy
from io import BytesIO
from timeit import default_timer as timer

import numpy as np
import pdfplumber
import trio
import xgboost as xgb
from huggingface_hub import snapshot_download
from PIL import Image
from pypdf import PdfReader as pdf2_read

from app.core.rag.common.file_utils import get_project_base_directory
from app.core.rag.common.misc_utils import pip_install_torch
from app.core.rag.deepdoc.vision import OCR, AscendLayoutRecognizer, LayoutRecognizer, Recognizer, TableStructureRecognizer
from app.core.rag.app.picture import vision_llm_chunk as picture_vision_llm_chunk
from app.core.rag.nlp import rag_tokenizer
from app.core.rag.prompts.generator import vision_llm_describe_prompt
from app.core.rag.common import settings

LOCK_KEY_pdfplumber = "global_shared_lock_pdfplumber"
if LOCK_KEY_pdfplumber not in sys.modules:
    sys.modules[LOCK_KEY_pdfplumber] = threading.Lock()


class RAGPdfParser:
    def __init__(self, **kwargs):
        """
        If you have trouble downloading HuggingFace models, -_^ this might help!!

        For Linux:
        export HF_ENDPOINT=https://hf-mirror.com

        For Windows:
        Good luck
        ^_-

        """

        self.ocr = OCR()
        self.parallel_limiter = None
        if settings.PARALLEL_DEVICES > 1:
            self.parallel_limiter = [trio.CapacityLimiter(1) for _ in range(settings.PARALLEL_DEVICES)]

        layout_recognizer_type = os.getenv("LAYOUT_RECOGNIZER_TYPE", "onnx").lower()
        if layout_recognizer_type not in ["onnx", "ascend"]:
            raise RuntimeError("Unsupported layout recognizer type.")

        if hasattr(self, "model_speciess"):
            recognizer_domain = "layout." + self.model_speciess
        else:
            recognizer_domain = "layout"

        if layout_recognizer_type == "ascend":
            logging.debug("Using Ascend LayoutRecognizer")
            self.layouter = AscendLayoutRecognizer(recognizer_domain)
        else:  # onnx
            logging.debug("Using Onnx LayoutRecognizer")
            self.layouter = LayoutRecognizer(recognizer_domain)
        self.tbl_det = TableStructureRecognizer()

        self.updown_cnt_mdl = xgb.Booster()
        try:
            pip_install_torch()
            import torch.cuda
            if torch.cuda.is_available():
                self.updown_cnt_mdl.set_param({"device": "cuda"})
        except Exception:
            logging.info("No torch found.")
        try:
            model_dir = os.path.join(get_project_base_directory(), "res/text_concat_xgb_v1.0")
            self.updown_cnt_mdl.load_model(os.path.join(model_dir, "updown_concat_xgb.model"))
        except Exception:
            model_dir = snapshot_download(repo_id="InfiniFlow/text_concat_xgb_v1.0", local_dir=os.path.join(get_project_base_directory(), "res/text_concat_xgb_v1.0"), local_dir_use_symlinks=False)
            self.updown_cnt_mdl.load_model(os.path.join(model_dir, "updown_concat_xgb.model"))

        self.page_from = 0
        self.column_num = 1

    def __char_width(self, c):
        return (c["x1"] - c["x0"]) // max(len(c["text"]), 1)

    def __height(self, c):
        return c["bottom"] - c["top"]

    def _x_dis(self, a, b):
        return min(abs(a["x1"] - b["x0"]), abs(a["x0"] - b["x1"]), abs(a["x0"] + a["x1"] - b["x0"] - b["x1"]) / 2)

    def _y_dis(self, a, b):
        return (b["top"] + b["bottom"] - a["top"] - a["bottom"]) / 2

    def _match_proj(self, b):
        proj_patt = [
            r"第[零一二三四五六七八九十百]+章",
            r"第[零一二三四五六七八九十百]+[条节]",
            r"[零一二三四五六七八九十百]+[、是 　]",
            r"[\(（][零一二三四五六七八九十百]+[）\)]",
            r"[\(（][0-9]+[）\)]",
            r"[0-9]+(、|\.[　 ]|）|\.[^0-9./a-zA-Z_%><-]{4,})",
            r"[0-9]+\.[0-9.]+(、|\.[ 　])",
            r"[⚫•➢①② ]",
        ]
        return any([re.match(p, b["text"]) for p in proj_patt])

    def _updown_concat_features(self, up, down):
        w = max(self.__char_width(up), self.__char_width(down))
        h = max(self.__height(up), self.__height(down))
        y_dis = self._y_dis(up, down)
        LEN = 6
        tks_down = rag_tokenizer.tokenize(down["text"][:LEN]).split()
        tks_up = rag_tokenizer.tokenize(up["text"][-LEN:]).split()
        tks_all = up["text"][-LEN:].strip() + (" " if re.match(r"[a-zA-Z0-9]+", up["text"][-1] + down["text"][0]) else "") + down["text"][:LEN].strip()
        tks_all = rag_tokenizer.tokenize(tks_all).split()
        fea = [
            up.get("R", -1) == down.get("R", -1),
            y_dis / h,
            down["page_number"] - up["page_number"],
            up["layout_type"] == down["layout_type"],
            up["layout_type"] == "text",
            down["layout_type"] == "text",
            up["layout_type"] == "table",
            down["layout_type"] == "table",
            True if re.search(r"([。？！；!?;+)）]|[a-z]\.)$", up["text"]) else False,
            True if re.search(r"[，：‘“、0-9（+-]$", up["text"]) else False,
            True if re.search(r"(^.?[/,?;:\]，。；：’”？！》】）-])", down["text"]) else False,
            True if re.match(r"[\(（][^\(\)（）]+[）\)]$", up["text"]) else False,
            True if re.search(r"[，,][^。.]+$", up["text"]) else False,
            True if re.search(r"[，,][^。.]+$", up["text"]) else False,
            True if re.search(r"[\(（][^\)）]+$", up["text"]) and re.search(r"[\)）]", down["text"]) else False,
            self._match_proj(down),
            True if re.match(r"[A-Z]", down["text"]) else False,
            True if re.match(r"[A-Z]", up["text"][-1]) else False,
            True if re.match(r"[a-z0-9]", up["text"][-1]) else False,
            True if re.match(r"[0-9.%,-]+$", down["text"]) else False,
            up["text"].strip()[-2:] == down["text"].strip()[-2:] if len(up["text"].strip()) > 1 and len(down["text"].strip()) > 1 else False,
            up["x0"] > down["x1"],
            abs(self.__height(up) - self.__height(down)) / min(self.__height(up), self.__height(down)),
            self._x_dis(up, down) / max(w, 0.000001),
            (len(up["text"]) - len(down["text"])) / max(len(up["text"]), len(down["text"])),
            len(tks_all) - len(tks_up) - len(tks_down),
            len(tks_down) - len(tks_up),
            tks_down[-1] == tks_up[-1] if tks_down and tks_up else False,
            max(down["in_row"], up["in_row"]),
            abs(down["in_row"] - up["in_row"]),
            len(tks_down) == 1 and rag_tokenizer.tag(tks_down[0]).find("n") >= 0,
            len(tks_up) == 1 and rag_tokenizer.tag(tks_up[0]).find("n") >= 0,
        ]
        return fea

    @staticmethod
    def sort_X_by_page(arr, threshold):
        # sort using y1 first and then x1
        arr = sorted(arr, key=lambda r: (r["page_number"], r["x0"], r["top"]))
        for i in range(len(arr) - 1):
            for j in range(i, -1, -1):
                # restore the order using th
                if abs(arr[j + 1]["x0"] - arr[j]["x0"]) < threshold and arr[j + 1]["top"] < arr[j]["top"] and arr[j + 1]["page_number"] == arr[j]["page_number"]:
                    tmp = arr[j]
                    arr[j] = arr[j + 1]
                    arr[j + 1] = tmp
        return arr

    def _has_color(self, o):
        if o.get("ncs", "") == "DeviceGray":
            if o["stroking_color"] and o["stroking_color"][0] == 1 and o["non_stroking_color"] and o["non_stroking_color"][0] == 1:
                if re.match(r"[a-zT_\[\]\(\)-]+", o.get("text", "")):
                    return False
        return True

    def _table_transformer_job(self, ZM):
        logging.debug("Table processing...")
        imgs, pos = [], []
        tbcnt = [0]
        MARGIN = 10
        self.tb_cpns = []
        assert len(self.page_layout) == len(self.page_images)
        for p, tbls in enumerate(self.page_layout):  # for page
            tbls = [f for f in tbls if f["type"] == "table"]
            tbcnt.append(len(tbls))
            if not tbls:
                continue
            for tb in tbls:  # for table
                left, top, right, bott = tb["x0"] - MARGIN, tb["top"] - MARGIN, tb["x1"] + MARGIN, tb["bottom"] + MARGIN
                left *= ZM
                top *= ZM
                right *= ZM
                bott *= ZM
                pos.append((left, top))
                imgs.append(self.page_images[p].crop((left, top, right, bott)))

        assert len(self.page_images) == len(tbcnt) - 1
        if not imgs:
            return
        recos = self.tbl_det(imgs)
        tbcnt = np.cumsum(tbcnt)
        for i in range(len(tbcnt) - 1):  # for page
            pg = []
            for j, tb_items in enumerate(recos[tbcnt[i] : tbcnt[i + 1]]):  # for table
                poss = pos[tbcnt[i] : tbcnt[i + 1]]
                for it in tb_items:  # for table components
                    it["x0"] = it["x0"] + poss[j][0]
                    it["x1"] = it["x1"] + poss[j][0]
                    it["top"] = it["top"] + poss[j][1]
                    it["bottom"] = it["bottom"] + poss[j][1]
                    for n in ["x0", "x1", "top", "bottom"]:
                        it[n] /= ZM
                    it["top"] += self.page_cum_height[i]
                    it["bottom"] += self.page_cum_height[i]
                    it["pn"] = i
                    it["layoutno"] = j
                    pg.append(it)
            self.tb_cpns.extend(pg)

        def gather(kwd, fzy=10, ption=0.6):
            eles = Recognizer.sort_Y_firstly([r for r in self.tb_cpns if re.match(kwd, r["label"])], fzy)
            eles = Recognizer.layouts_cleanup(self.boxes, eles, 5, ption)
            return Recognizer.sort_Y_firstly(eles, 0)

        # add R,H,C,SP tag to boxes within table layout
        headers = gather(r".*header$")
        rows = gather(r".* (row|header)")
        spans = gather(r".*spanning")
        clmns = sorted([r for r in self.tb_cpns if re.match(r"table column$", r["label"])], key=lambda x: (x["pn"], x["layoutno"], x["x0"]))
        clmns = Recognizer.layouts_cleanup(self.boxes, clmns, 5, 0.5)
        for b in self.boxes:
            if b.get("layout_type", "") != "table":
                continue
            ii = Recognizer.find_overlapped_with_threshold(b, rows, thr=0.3)
            if ii is not None:
                b["R"] = ii
                b["R_top"] = rows[ii]["top"]
                b["R_bott"] = rows[ii]["bottom"]

            ii = Recognizer.find_overlapped_with_threshold(b, headers, thr=0.3)
            if ii is not None:
                b["H_top"] = headers[ii]["top"]
                b["H_bott"] = headers[ii]["bottom"]
                b["H_left"] = headers[ii]["x0"]
                b["H_right"] = headers[ii]["x1"]
                b["H"] = ii

            ii = Recognizer.find_horizontally_tightest_fit(b, clmns)
            if ii is not None:
                b["C"] = ii
                b["C_left"] = clmns[ii]["x0"]
                b["C_right"] = clmns[ii]["x1"]

            ii = Recognizer.find_overlapped_with_threshold(b, spans, thr=0.3)
            if ii is not None:
                b["H_top"] = spans[ii]["top"]
                b["H_bott"] = spans[ii]["bottom"]
                b["H_left"] = spans[ii]["x0"]
                b["H_right"] = spans[ii]["x1"]
                b["SP"] = ii

    def __ocr(self, pagenum, img, chars, ZM=3, device_id: int | None = None):
        start = timer()
        bxs = self.ocr.detect(np.array(img), device_id)
        logging.info(f"__ocr detecting boxes of a image cost ({timer() - start}s)")

        start = timer()
        if not bxs:
            self.boxes.append([])
            return
        bxs = [(line[0], line[1][0]) for line in bxs]
        bxs = Recognizer.sort_Y_firstly(
            [
                {"x0": b[0][0] / ZM, "x1": b[1][0] / ZM, "top": b[0][1] / ZM, "text": "", "txt": t, "bottom": b[-1][1] / ZM, "chars": [], "page_number": pagenum}
                for b, t in bxs
                if b[0][0] <= b[1][0] and b[0][1] <= b[-1][1]
            ],
            self.mean_height[pagenum - 1] / 3,
        )

        # merge chars in the same rect
        for c in chars:
            ii = Recognizer.find_overlapped(c, bxs)
            if ii is None:
                self.lefted_chars.append(c)
                continue
            ch = c["bottom"] - c["top"]
            bh = bxs[ii]["bottom"] - bxs[ii]["top"]
            if abs(ch - bh) / max(ch, bh) >= 0.7 and c["text"] != " ":
                self.lefted_chars.append(c)
                continue
            bxs[ii]["chars"].append(c)

        for b in bxs:
            if not b["chars"]:
                del b["chars"]
                continue
            m_ht = np.mean([c["height"] for c in b["chars"]])
            for c in Recognizer.sort_Y_firstly(b["chars"], m_ht):
                if c["text"] == " " and b["text"]:
                    if re.match(r"[0-9a-zA-Zа-яА-Я,.?;:!%%]", b["text"][-1]):
                        b["text"] += " "
                else:
                    b["text"] += c["text"]
            del b["chars"]

        logging.info(f"__ocr sorting {len(chars)} chars cost {timer() - start}s")
        start = timer()
        boxes_to_reg = []
        img_np = np.array(img)
        for b in bxs:
            if not b["text"]:
                left, right, top, bott = b["x0"] * ZM, b["x1"] * ZM, b["top"] * ZM, b["bottom"] * ZM
                b["box_image"] = self.ocr.get_rotate_crop_image(img_np, np.array([[left, top], [right, top], [right, bott], [left, bott]], dtype=np.float32))
                boxes_to_reg.append(b)
            del b["txt"]
        texts = self.ocr.recognize_batch([b["box_image"] for b in boxes_to_reg], device_id)
        for i in range(len(boxes_to_reg)):
            boxes_to_reg[i]["text"] = texts[i]
            del boxes_to_reg[i]["box_image"]
        logging.info(f"__ocr recognize {len(bxs)} boxes cost {timer() - start}s")
        bxs = [b for b in bxs if b["text"]]
        if self.mean_height[pagenum - 1] == 0:
            self.mean_height[pagenum - 1] = np.median([b["bottom"] - b["top"] for b in bxs])
        self.boxes.append(bxs)

    def _layouts_rec(self, ZM, drop=True):
        assert len(self.page_images) == len(self.boxes)
        self.boxes, self.page_layout = self.layouter(self.page_images, self.boxes, ZM, drop=drop)
        # cumlative Y
        for i in range(len(self.boxes)):
            self.boxes[i]["top"] += self.page_cum_height[self.boxes[i]["page_number"] - 1]
            self.boxes[i]["bottom"] += self.page_cum_height[self.boxes[i]["page_number"] - 1]

    def _assign_column(self, boxes, zoomin=3):
        if not boxes:
            return boxes

        if all("col_id" in b for b in boxes):
            return boxes

        by_page = defaultdict(list)
        for b in boxes:
            by_page[b["page_number"]].append(b)

        page_info = {}  # pg -> dict(page_w, left_edge, cand_cols)
        counter = Counter()

        for pg, bxs in by_page.items():
            if not bxs:
                page_info[pg] = {"page_w": 1.0, "left_edge": 0.0, "cand": 1}
                counter[1] += 1
                continue

            if hasattr(self, "page_images") and self.page_images and len(self.page_images) >= pg:
                page_w = self.page_images[pg - 1].size[0] / max(1, zoomin)
                left_edge = 0.0
            else:
                xs0 = [box["x0"] for box in bxs]
                xs1 = [box["x1"] for box in bxs]
                left_edge = float(min(xs0))
                page_w = max(1.0, float(max(xs1) - left_edge))

            widths = [max(1.0, (box["x1"] - box["x0"])) for box in bxs]
            median_w = float(np.median(widths)) if widths else 1.0

            raw_cols = int(page_w / max(1.0, median_w))

            # cand = raw_cols if (raw_cols >= 2 and median_w < page_w / raw_cols * 0.8) else 1
            cand = raw_cols

            page_info[pg] = {"page_w": page_w, "left_edge": left_edge, "cand": cand}
            counter[cand] += 1

            logging.info(f"[Page {pg}] median_w={median_w:.2f}, page_w={page_w:.2f}, raw_cols={raw_cols}, cand={cand}")

        global_cols = counter.most_common(1)[0][0]
        logging.info(f"Global column_num decided by majority: {global_cols}")

        for pg, bxs in by_page.items():
            if not bxs:
                continue

            page_w = page_info[pg]["page_w"]
            left_edge = page_info[pg]["left_edge"]

            if global_cols == 1:
                for box in bxs:
                    box["col_id"] = 0
                continue

            for box in bxs:
                w = box["x1"] - box["x0"]
                if w >= 0.8 * page_w:
                    box["col_id"] = 0
                    continue
                cx = 0.5 * (box["x0"] + box["x1"])
                norm_cx = (cx - left_edge) / page_w
                norm_cx = max(0.0, min(norm_cx, 0.999999))
                box["col_id"] = int(min(global_cols - 1, norm_cx * global_cols))

        return boxes

    def _text_merge(self, zoomin=3):
        # merge adjusted boxes
        bxs = self._assign_column(self.boxes, zoomin)

        def end_with(b, txt):
            txt = txt.strip()
            tt = b.get("text", "").strip()
            return tt and tt.find(txt) == len(tt) - len(txt)

        def start_with(b, txts):
            tt = b.get("text", "").strip()
            return tt and any([tt.find(t.strip()) == 0 for t in txts])

        # horizontally merge adjacent box with the same layout
        i = 0
        while i < len(bxs) - 1:
            b = bxs[i]
            b_ = bxs[i + 1]

            if b["page_number"] != b_["page_number"] or b.get("col_id") != b_.get("col_id"):
                i += 1
                continue

            if b.get("layoutno", "0") != b_.get("layoutno", "1") or b.get("layout_type", "") in ["table", "figure", "equation"]:
                i += 1
                continue

            if abs(self._y_dis(b, b_)) < self.mean_height[bxs[i]["page_number"] - 1] / 3:
                # merge
                bxs[i]["x1"] = b_["x1"]
                bxs[i]["top"] = (b["top"] + b_["top"]) / 2
                bxs[i]["bottom"] = (b["bottom"] + b_["bottom"]) / 2
                bxs[i]["text"] += b_["text"]
                bxs.pop(i + 1)
                continue
            i += 1
        self.boxes = bxs

    def _naive_vertical_merge(self, zoomin=3):
        bxs = self._assign_column(self.boxes, zoomin)

        grouped = defaultdict(list)
        for b in bxs:
            grouped[(b["page_number"], b.get("col_id", 0))].append(b)

        merged_boxes = []
        for (pg, col), bxs in grouped.items():
            bxs = sorted(bxs, key=lambda x: (x["top"], x["x0"]))
            if not bxs:
                continue

            mh = self.mean_height[pg - 1] if self.mean_height else np.median([b["bottom"] - b["top"] for b in bxs]) or 10

            i = 0
            while i + 1 < len(bxs):
                b = bxs[i]
                b_ = bxs[i + 1]

                if b["page_number"] < b_["page_number"] and re.match(r"[0-9  •一—-]+$", b["text"]):
                    bxs.pop(i)
                    continue

                if not b["text"].strip():
                    bxs.pop(i)
                    continue

                if not b["text"].strip() or b.get("layoutno") != b_.get("layoutno"):
                    i += 1
                    continue

                if b_["top"] - b["bottom"] > mh * 1.5:
                    i += 1
                    continue

                overlap = max(0, min(b["x1"], b_["x1"]) - max(b["x0"], b_["x0"]))
                if overlap / max(1, min(b["x1"] - b["x0"], b_["x1"] - b_["x0"])) < 0.3:
                    i += 1
                    continue

                concatting_feats = [
                    b["text"].strip()[-1] in ",;:'\"，、‘“；：-",
                    len(b["text"].strip()) > 1 and b["text"].strip()[-2] in ",;:'\"，‘“、；：",
                    b_["text"].strip() and b_["text"].strip()[0] in "。；？！?”）),，、：",
                ]
                # features for not concating
                feats = [
                    b.get("layoutno", 0) != b_.get("layoutno", 0),
                    b["text"].strip()[-1] in "。？！?",
                    self.is_english and b["text"].strip()[-1] in ".!?",
                    b["page_number"] == b_["page_number"] and b_["top"] - b["bottom"] > self.mean_height[b["page_number"] - 1] * 1.5,
                    b["page_number"] < b_["page_number"] and abs(b["x0"] - b_["x0"]) > self.mean_width[b["page_number"] - 1] * 4,
                ]
                # split features
                detach_feats = [b["x1"] < b_["x0"], b["x0"] > b_["x1"]]
                if (any(feats) and not any(concatting_feats)) or any(detach_feats):
                    logging.debug(
                        "{} {} {} {}".format(
                            b["text"],
                            b_["text"],
                            any(feats),
                            any(concatting_feats),
                        )
                    )
                    i += 1
                    continue

                b["text"] = (b["text"].rstrip() + " " + b_["text"].lstrip()).strip()
                b["bottom"] = b_["bottom"]
                b["x0"] = min(b["x0"], b_["x0"])
                b["x1"] = max(b["x1"], b_["x1"])
                bxs.pop(i + 1)

            merged_boxes.extend(bxs)

        self.boxes = sorted(merged_boxes, key=lambda x: (x["page_number"], x.get("col_id", 0), x["top"]))

    def _final_reading_order_merge(self, zoomin=3):
        if not self.boxes:
            return

        self.boxes = self._assign_column(self.boxes, zoomin=zoomin)

        pages = defaultdict(lambda: defaultdict(list))
        for b in self.boxes:
            pg = b["page_number"]
            col = b.get("col_id", 0)
            pages[pg][col].append(b)

        for pg in pages:
            for col in pages[pg]:
                pages[pg][col].sort(key=lambda x: (x["top"], x["x0"]))

        new_boxes = []
        for pg in sorted(pages.keys()):
            for col in sorted(pages[pg].keys()):
                new_boxes.extend(pages[pg][col])

        self.boxes = new_boxes

    def _concat_downward(self, concat_between_pages=True):
        self.boxes = Recognizer.sort_Y_firstly(self.boxes, 0)
        return

        # count boxes in the same row as a feature
        for i in range(len(self.boxes)):
            mh = self.mean_height[self.boxes[i]["page_number"] - 1]
            self.boxes[i]["in_row"] = 0
            j = max(0, i - 12)
            while j < min(i + 12, len(self.boxes)):
                if j == i:
                    j += 1
                    continue
                ydis = self._y_dis(self.boxes[i], self.boxes[j]) / mh
                if abs(ydis) < 1:
                    self.boxes[i]["in_row"] += 1
                elif ydis > 0:
                    break
                j += 1

        # concat between rows
        boxes = deepcopy(self.boxes)
        blocks = []
        while boxes:
            chunks = []

            def dfs(up, dp):
                chunks.append(up)
                i = dp
                while i < min(dp + 12, len(boxes)):
                    ydis = self._y_dis(up, boxes[i])
                    smpg = up["page_number"] == boxes[i]["page_number"]
                    mh = self.mean_height[up["page_number"] - 1]
                    mw = self.mean_width[up["page_number"] - 1]
                    if smpg and ydis > mh * 4:
                        break
                    if not smpg and ydis > mh * 16:
                        break
                    down = boxes[i]
                    if not concat_between_pages and down["page_number"] > up["page_number"]:
                        break

                    if up.get("R", "") != down.get("R", "") and up["text"][-1] != "，":
                        i += 1
                        continue

                    if re.match(r"[0-9]{2,3}/[0-9]{3}$", up["text"]) or re.match(r"[0-9]{2,3}/[0-9]{3}$", down["text"]) or not down["text"].strip():
                        i += 1
                        continue

                    if not down["text"].strip() or not up["text"].strip():
                        i += 1
                        continue

                    if up["x1"] < down["x0"] - 10 * mw or up["x0"] > down["x1"] + 10 * mw:
                        i += 1
                        continue

                    if i - dp < 5 and up.get("layout_type") == "text":
                        if up.get("layoutno", "1") == down.get("layoutno", "2"):
                            dfs(down, i + 1)
                            boxes.pop(i)
                            return
                        i += 1
                        continue

                    fea = self._updown_concat_features(up, down)
                    if self.updown_cnt_mdl.predict(xgb.DMatrix([fea]))[0] <= 0.5:
                        i += 1
                        continue
                    dfs(down, i + 1)
                    boxes.pop(i)
                    return

            dfs(boxes[0], 1)
            boxes.pop(0)
            if chunks:
                blocks.append(chunks)

        # concat within each block
        boxes = []
        for b in blocks:
            if len(b) == 1:
                boxes.append(b[0])
                continue
            t = b[0]
            for c in b[1:]:
                t["text"] = t["text"].strip()
                c["text"] = c["text"].strip()
                if not c["text"]:
                    continue
                if t["text"] and re.match(r"[0-9\.a-zA-Z]+$", t["text"][-1] + c["text"][-1]):
                    t["text"] += " "
                t["text"] += c["text"]
                t["x0"] = min(t["x0"], c["x0"])
                t["x1"] = max(t["x1"], c["x1"])
                t["page_number"] = min(t["page_number"], c["page_number"])
                t["bottom"] = c["bottom"]
                if not t["layout_type"] and c["layout_type"]:
                    t["layout_type"] = c["layout_type"]
            boxes.append(t)

        self.boxes = Recognizer.sort_Y_firstly(boxes, 0)

    def _filter_forpages(self):
        if not self.boxes:
            return
        findit = False
        i = 0
        while i < len(self.boxes):
            if not re.match(r"(contents|目录|目次|table of contents|致谢|acknowledge)$", re.sub(r"( | |\u3000)+", "", self.boxes[i]["text"].lower())):
                i += 1
                continue
            findit = True
            eng = re.match(r"[0-9a-zA-Z :'.-]{5,}", self.boxes[i]["text"].strip())
            self.boxes.pop(i)
            if i >= len(self.boxes):
                break
            prefix = self.boxes[i]["text"].strip()[:3] if not eng else " ".join(self.boxes[i]["text"].strip().split()[:2])
            while not prefix:
                self.boxes.pop(i)
                if i >= len(self.boxes):
                    break
                prefix = self.boxes[i]["text"].strip()[:3] if not eng else " ".join(self.boxes[i]["text"].strip().split()[:2])
            self.boxes.pop(i)
            if i >= len(self.boxes) or not prefix:
                break
            for j in range(i, min(i + 128, len(self.boxes))):
                if not re.match(prefix, self.boxes[j]["text"]):
                    continue
                for k in range(i, j):
                    self.boxes.pop(i)
                break
        if findit:
            return

        page_dirty = [0] * len(self.page_images)
        for b in self.boxes:
            if re.search(r"(··|··|··)", b["text"]):
                page_dirty[b["page_number"] - 1] += 1
        page_dirty = set([i + 1 for i, t in enumerate(page_dirty) if t > 3])
        if not page_dirty:
            return
        i = 0
        while i < len(self.boxes):
            if self.boxes[i]["page_number"] in page_dirty:
                self.boxes.pop(i)
                continue
            i += 1

    def _merge_with_same_bullet(self):
        i = 0
        while i + 1 < len(self.boxes):
            b = self.boxes[i]
            b_ = self.boxes[i + 1]
            if not b["text"].strip():
                self.boxes.pop(i)
                continue
            if not b_["text"].strip():
                self.boxes.pop(i + 1)
                continue

            if (
                b["text"].strip()[0] != b_["text"].strip()[0]
                or b["text"].strip()[0].lower() in set("qwertyuopasdfghjklzxcvbnm")
                or rag_tokenizer.is_chinese(b["text"].strip()[0])
                or b["top"] > b_["bottom"]
            ):
                i += 1
                continue
            b_["text"] = b["text"] + "\n" + b_["text"]
            b_["x0"] = min(b["x0"], b_["x0"])
            b_["x1"] = max(b["x1"], b_["x1"])
            b_["top"] = b["top"]
            self.boxes.pop(i)

    def _extract_table_figure(self, need_image, ZM, return_html, need_position, separate_tables_figures=False):
        tables = {}
        figures = {}
        # extract figure and table boxes
        i = 0
        lst_lout_no = ""
        nomerge_lout_no = []
        while i < len(self.boxes):
            if "layoutno" not in self.boxes[i]:
                i += 1
                continue
            lout_no = str(self.boxes[i]["page_number"]) + "-" + str(self.boxes[i]["layoutno"])
            if TableStructureRecognizer.is_caption(self.boxes[i]) or self.boxes[i]["layout_type"] in ["table caption", "title", "figure caption", "reference"]:
                nomerge_lout_no.append(lst_lout_no)
            if self.boxes[i]["layout_type"] == "table":
                if re.match(r"(数据|资料|图表)*来源[:： ]", self.boxes[i]["text"]):
                    self.boxes.pop(i)
                    continue
                if lout_no not in tables:
                    tables[lout_no] = []
                tables[lout_no].append(self.boxes[i])
                self.boxes.pop(i)
                lst_lout_no = lout_no
                continue
            if need_image and self.boxes[i]["layout_type"] == "figure":
                if re.match(r"(数据|资料|图表)*来源[:： ]", self.boxes[i]["text"]):
                    self.boxes.pop(i)
                    continue
                if lout_no not in figures:
                    figures[lout_no] = []
                figures[lout_no].append(self.boxes[i])
                self.boxes.pop(i)
                lst_lout_no = lout_no
                continue
            i += 1

        # merge table on different pages
        nomerge_lout_no = set(nomerge_lout_no)
        tbls = sorted([(k, bxs) for k, bxs in tables.items()], key=lambda x: (x[1][0]["top"], x[1][0]["x0"]))

        i = len(tbls) - 1
        while i - 1 >= 0:
            k0, bxs0 = tbls[i - 1]
            k, bxs = tbls[i]
            i -= 1
            if k0 in nomerge_lout_no:
                continue
            if bxs[0]["page_number"] == bxs0[0]["page_number"]:
                continue
            if bxs[0]["page_number"] - bxs0[0]["page_number"] > 1:
                continue
            mh = self.mean_height[bxs[0]["page_number"] - 1]
            if self._y_dis(bxs0[-1], bxs[0]) > mh * 23:
                continue
            tables[k0].extend(tables[k])
            del tables[k]

        def x_overlapped(a, b):
            return not any([a["x1"] < b["x0"], a["x0"] > b["x1"]])

        # find captions and pop out
        i = 0
        while i < len(self.boxes):
            c = self.boxes[i]
            # mh = self.mean_height[c["page_number"]-1]
            if not TableStructureRecognizer.is_caption(c):
                i += 1
                continue

            # find the nearest layouts
            def nearest(tbls):
                nonlocal c
                mink = ""
                minv = 1000000000
                for k, bxs in tbls.items():
                    for b in bxs:
                        if b.get("layout_type", "").find("caption") >= 0:
                            continue
                        y_dis = self._y_dis(c, b)
                        x_dis = self._x_dis(c, b) if not x_overlapped(c, b) else 0
                        dis = y_dis * y_dis + x_dis * x_dis
                        if dis < minv:
                            mink = k
                            minv = dis
                return mink, minv

            tk, tv = nearest(tables)
            fk, fv = nearest(figures)
            # if min(tv, fv) > 2000:
            #    i += 1
            #    continue
            if tv < fv and tk:
                tables[tk].insert(0, c)
                logging.debug("TABLE:" + self.boxes[i]["text"] + "; Cap: " + tk)
            elif fk:
                figures[fk].insert(0, c)
                logging.debug("FIGURE:" + self.boxes[i]["text"] + "; Cap: " + tk)
            self.boxes.pop(i)

        def cropout(bxs, ltype, poss):
            nonlocal ZM
            pn = set([b["page_number"] - 1 for b in bxs])
            if len(pn) < 2:
                pn = list(pn)[0]
                ht = self.page_cum_height[pn]
                b = {"x0": np.min([b["x0"] for b in bxs]), "top": np.min([b["top"] for b in bxs]) - ht, "x1": np.max([b["x1"] for b in bxs]), "bottom": np.max([b["bottom"] for b in bxs]) - ht}
                louts = [layout for layout in self.page_layout[pn] if layout["type"] == ltype]
                ii = Recognizer.find_overlapped(b, louts, naive=True)
                if ii is not None:
                    b = louts[ii]
                else:
                    logging.warning(f"Missing layout match: {pn + 1},%s" % (bxs[0].get("layoutno", "")))

                left, top, right, bott = b["x0"], b["top"], b["x1"], b["bottom"]
                if right < left:
                    right = left + 1
                poss.append((pn + self.page_from, left, right, top, bott))
                return self.page_images[pn].crop((left * ZM, top * ZM, right * ZM, bott * ZM))
            pn = {}
            for b in bxs:
                p = b["page_number"] - 1
                if p not in pn:
                    pn[p] = []
                pn[p].append(b)
            pn = sorted(pn.items(), key=lambda x: x[0])
            imgs = [cropout(arr, ltype, poss) for p, arr in pn]
            pic = Image.new("RGB", (int(np.max([i.size[0] for i in imgs])), int(np.sum([m.size[1] for m in imgs]))), (245, 245, 245))
            height = 0
            for img in imgs:
                pic.paste(img, (0, int(height)))
                height += img.size[1]
            return pic

        res = []
        positions = []
        figure_results = []
        figure_positions = []
        # crop figure out and add caption
        for k, bxs in figures.items():
            txt = "\n".join([b["text"] for b in bxs])
            if not txt:
                continue

            poss = []

            if separate_tables_figures:
                figure_results.append((cropout(bxs, "figure", poss), [txt]))
                figure_positions.append(poss)
            else:
                res.append((cropout(bxs, "figure", poss), [txt]))
                positions.append(poss)

        for k, bxs in tables.items():
            if not bxs:
                continue
            bxs = Recognizer.sort_Y_firstly(bxs, np.mean([(b["bottom"] - b["top"]) / 2 for b in bxs]))

            poss = []

            res.append((cropout(bxs, "table", poss), self.tbl_det.construct_table(bxs, html=return_html, is_english=self.is_english)))
            positions.append(poss)

        if separate_tables_figures:
            assert len(positions) + len(figure_positions) == len(res) + len(figure_results)
            if need_position:
                return list(zip(res, positions)), list(zip(figure_results, figure_positions))
            else:
                return res, figure_results
        else:
            assert len(positions) == len(res)
            if need_position:
                return list(zip(res, positions))
            else:
                return res

    def proj_match(self, line):
        if len(line) <= 2:
            return
        if re.match(r"[0-9 ().,%%+/-]+$", line):
            return False
        for p, j in [
            (r"第[零一二三四五六七八九十百]+章", 1),
            (r"第[零一二三四五六七八九十百]+[条节]", 2),
            (r"[零一二三四五六七八九十百]+[、 　]", 3),
            (r"[\(（][零一二三四五六七八九十百]+[）\)]", 4),
            (r"[0-9]+(、|\.[　 ]|\.[^0-9])", 5),
            (r"[0-9]+\.[0-9]+(、|[. 　]|[^0-9])", 6),
            (r"[0-9]+\.[0-9]+\.[0-9]+(、|[ 　]|[^0-9])", 7),
            (r"[0-9]+\.[0-9]+\.[0-9]+\.[0-9]+(、|[ 　]|[^0-9])", 8),
            (r".{,48}[：:?？]$", 9),
            (r"[0-9]+）", 10),
            (r"[\(（][0-9]+[）\)]", 11),
            (r"[零一二三四五六七八九十百]+是", 12),
            (r"[⚫•➢✓]", 12),
        ]:
            if re.match(p, line):
                return j
        return

    def _line_tag(self, bx, ZM):
        pn = [bx["page_number"]]
        top = bx["top"] - self.page_cum_height[pn[0] - 1]
        bott = bx["bottom"] - self.page_cum_height[pn[0] - 1]
        page_images_cnt = len(self.page_images)
        if pn[-1] - 1 >= page_images_cnt:
            return ""
        while bott * ZM > self.page_images[pn[-1] - 1].size[1]:
            bott -= self.page_images[pn[-1] - 1].size[1] / ZM
            pn.append(pn[-1] + 1)
            if pn[-1] - 1 >= page_images_cnt:
                return ""

        return "@@{}\t{:.1f}\t{:.1f}\t{:.1f}\t{:.1f}##".format("-".join([str(p) for p in pn]), bx["x0"], bx["x1"], top, bott)

    def __filterout_scraps(self, boxes, ZM):
        def width(b):
            return b["x1"] - b["x0"]

        def height(b):
            return b["bottom"] - b["top"]

        def usefull(b):
            if b.get("layout_type"):
                return True
            if width(b) > self.page_images[b["page_number"] - 1].size[0] / ZM / 3:
                return True
            if b["bottom"] - b["top"] > self.mean_height[b["page_number"] - 1]:
                return True
            return False

        res = []
        while boxes:
            lines = []
            widths = []
            pw = self.page_images[boxes[0]["page_number"] - 1].size[0] / ZM
            mh = self.mean_height[boxes[0]["page_number"] - 1]
            mj = self.proj_match(boxes[0]["text"]) or boxes[0].get("layout_type", "") == "title"

            def dfs(line, st):
                nonlocal mh, pw, lines, widths
                lines.append(line)
                widths.append(width(line))
                mmj = self.proj_match(line["text"]) or line.get("layout_type", "") == "title"
                for i in range(st + 1, min(st + 20, len(boxes))):
                    if (boxes[i]["page_number"] - line["page_number"]) > 0:
                        break
                    if not mmj and self._y_dis(line, boxes[i]) >= 3 * mh and height(line) < 1.5 * mh:
                        break

                    if not usefull(boxes[i]):
                        continue
                    if mmj or (self._x_dis(boxes[i], line) < pw / 10):
                        # and abs(width(boxes[i])-width_mean)/max(width(boxes[i]),width_mean)<0.5):
                        # concat following
                        dfs(boxes[i], i)
                        boxes.pop(i)
                        break

            try:
                if usefull(boxes[0]):
                    dfs(boxes[0], 0)
                else:
                    logging.debug("WASTE: " + boxes[0]["text"])
            except Exception:
                pass
            boxes.pop(0)
            mw = np.mean(widths)
            if mj or mw / pw >= 0.35 or mw > 200:
                res.append("\n".join([c["text"] + self._line_tag(c, ZM) for c in lines]))
            else:
                logging.debug("REMOVED: " + "<<".join([c["text"] for c in lines]))

        return "\n\n".join(res)

    @staticmethod
    def total_page_number(fnm, binary=None):
        try:
            with sys.modules[LOCK_KEY_pdfplumber]:
                pdf = pdfplumber.open(fnm) if not binary else pdfplumber.open(BytesIO(binary))
            total_page = len(pdf.pages)
            pdf.close()
            return total_page
        except Exception:
            logging.exception("total_page_number")

    def __images__(self, fnm, zoomin=3, page_from=0, page_to=299, callback=None):
        self.lefted_chars = []
        self.mean_height = []
        self.mean_width = []
        self.boxes = []
        self.garbages = {}
        self.page_cum_height = [0]
        self.page_layout = []
        self.page_from = page_from
        start = timer()
        try:
            with sys.modules[LOCK_KEY_pdfplumber]:
                with pdfplumber.open(fnm) if isinstance(fnm, str) else pdfplumber.open(BytesIO(fnm)) as pdf:
                    self.pdf = pdf
                    self.page_images = [p.to_image(resolution=72 * zoomin, antialias=True).annotated for i, p in enumerate(self.pdf.pages[page_from:page_to])]

                    try:
                        self.page_chars = [[c for c in page.dedupe_chars().chars if self._has_color(c)] for page in self.pdf.pages[page_from:page_to]]
                    except Exception as e:
                        logging.warning(f"Failed to extract characters for pages {page_from}-{page_to}: {str(e)}")
                        self.page_chars = [[] for _ in range(page_to - page_from)]  # If failed to extract, using empty list instead.

                    self.total_page = len(self.pdf.pages)

        except Exception:
            logging.exception("RAGPdfParser __images__")
        logging.info(f"__images__ dedupe_chars cost {timer() - start}s")

        self.outlines = []
        try:
            with pdf2_read(fnm if isinstance(fnm, str) else BytesIO(fnm)) as pdf:
                self.pdf = pdf

                outlines = self.pdf.outline

                def dfs(arr, depth):
                    for a in arr:
                        if isinstance(a, dict):
                            self.outlines.append((a["/Title"], depth))
                            continue
                        dfs(a, depth + 1)

                dfs(outlines, 0)

        except Exception as e:
            logging.warning(f"Outlines exception: {e}")

        if not self.outlines:
            logging.warning("Miss outlines")

        logging.debug("Images converted.")
        self.is_english = [
            re.search(r"[a-zA-Z0-9,/¸;:'\[\]\(\)!@#$%^&*\"?<>._-]{30,}", "".join(random.choices([c["text"] for c in self.page_chars[i]], k=min(100, len(self.page_chars[i])))))
            for i in range(len(self.page_chars))
        ]
        if sum([1 if e else 0 for e in self.is_english]) > len(self.page_images) / 2:
            self.is_english = True
        else:
            self.is_english = False

        async def __img_ocr(i, id, img, chars, limiter):
            j = 0
            while j + 1 < len(chars):
                if (
                    chars[j]["text"]
                    and chars[j + 1]["text"]
                    and re.match(r"[0-9a-zA-Z,.:;!%]+", chars[j]["text"] + chars[j + 1]["text"])
                    and chars[j + 1]["x0"] - chars[j]["x1"] >= min(chars[j + 1]["width"], chars[j]["width"]) / 2
                ):
                    chars[j]["text"] += " "
                j += 1

            if limiter:
                async with limiter:
                    await trio.to_thread.run_sync(lambda: self.__ocr(i + 1, img, chars, zoomin, id))
            else:
                self.__ocr(i + 1, img, chars, zoomin, id)

            if callback and i % 6 == 5:
                callback((i + 1) * 0.6 / len(self.page_images))

        async def __img_ocr_launcher():
            def __ocr_preprocess():
                chars = self.page_chars[i] if not self.is_english else []
                self.mean_height.append(np.median(sorted([c["height"] for c in chars])) if chars else 0)
                self.mean_width.append(np.median(sorted([c["width"] for c in chars])) if chars else 8)
                self.page_cum_height.append(img.size[1] / zoomin)
                return chars

            if self.parallel_limiter:
                async with trio.open_nursery() as nursery:
                    for i, img in enumerate(self.page_images):
                        chars = __ocr_preprocess()

                        nursery.start_soon(__img_ocr, i, i % settings.PARALLEL_DEVICES, img, chars, self.parallel_limiter[i % settings.PARALLEL_DEVICES])
                        await trio.sleep(0.1)
            else:
                for i, img in enumerate(self.page_images):
                    chars = __ocr_preprocess()
                    await __img_ocr(i, 0, img, chars, None)

        start = timer()

        trio.run(__img_ocr_launcher)

        logging.info(f"__images__ {len(self.page_images)} pages cost {timer() - start}s")

        if not self.is_english and not any([c for c in self.page_chars]) and self.boxes:
            bxes = [b for bxs in self.boxes for b in bxs]
            self.is_english = re.search(r"[\na-zA-Z0-9,/¸;:'\[\]\(\)!@#$%^&*\"?<>._-]{30,}", "".join([b["text"] for b in random.choices(bxes, k=min(30, len(bxes)))]))

        logging.debug(f"Is it English: {self.is_english}")

        self.page_cum_height = np.cumsum(self.page_cum_height)
        assert len(self.page_cum_height) == len(self.page_images) + 1
        if len(self.boxes) == 0 and zoomin < 9:
            self.__images__(fnm, zoomin * 3, page_from, page_to, callback)

    def __call__(self, fnm, need_image=True, zoomin=3, return_html=False):
        self.__images__(fnm, zoomin)
        self._layouts_rec(zoomin)
        self._table_transformer_job(zoomin)
        self._text_merge()
        self._concat_downward()
        self._filter_forpages()
        tbls = self._extract_table_figure(need_image, zoomin, return_html, False)
        return self.__filterout_scraps(deepcopy(self.boxes), zoomin), tbls

    def parse_into_bboxes(self, fnm, callback=None, zoomin=3):
        start = timer()
        self.__images__(fnm, zoomin, callback=callback)
        if callback:
            callback(0.40, "OCR finished ({:.2f}s)".format(timer() - start))

        start = timer()
        self._layouts_rec(zoomin)
        if callback:
            callback(0.63, "Layout analysis ({:.2f}s)".format(timer() - start))

        start = timer()
        self._table_transformer_job(zoomin)
        if callback:
            callback(0.83, "Table analysis ({:.2f}s)".format(timer() - start))

        start = timer()
        self._text_merge()
        self._concat_downward()
        self._naive_vertical_merge(zoomin)
        if callback:
            callback(0.92, "Text merged ({:.2f}s)".format(timer() - start))

        start = timer()
        tbls, figs = self._extract_table_figure(True, zoomin, True, True, True)

        def insert_table_figures(tbls_or_figs, layout_type):
            def min_rectangle_distance(rect1, rect2):
                pn1, left1, right1, top1, bottom1 = rect1
                pn2, left2, right2, top2, bottom2 = rect2
                if right1 >= left2 and right2 >= left1 and bottom1 >= top2 and bottom2 >= top1:
                    return 0
                if right1 < left2:
                    dx = left2 - right1
                elif right2 < left1:
                    dx = left1 - right2
                else:
                    dx = 0
                if bottom1 < top2:
                    dy = top2 - bottom1
                elif bottom2 < top1:
                    dy = top1 - bottom2
                else:
                    dy = 0
                return math.sqrt(dx * dx + dy * dy)  # + (pn2-pn1)*10000

            for (img, txt), poss in tbls_or_figs:
                bboxes = [(i, (b["page_number"], b["x0"], b["x1"], b["top"], b["bottom"])) for i, b in enumerate(self.boxes)]
                dists = [
                    (min_rectangle_distance((pn, left, right, top + self.page_cum_height[pn], bott + self.page_cum_height[pn]), rect), i) for i, rect in bboxes for pn, left, right, top, bott in poss
                ]
                min_i = np.argmin(dists, axis=0)[0]
                min_i, rect = bboxes[dists[min_i][-1]]
                if isinstance(txt, list):
                    txt = "\n".join(txt)
                pn, left, right, top, bott = poss[0]
                if self.boxes[min_i]["bottom"] < top + self.page_cum_height[pn]:
                    min_i += 1
                self.boxes.insert(
                    min_i,
                    {
                        "page_number": pn + 1,
                        "x0": left,
                        "x1": right,
                        "top": top + self.page_cum_height[pn],
                        "bottom": bott + self.page_cum_height[pn],
                        "layout_type": layout_type,
                        "text": txt,
                        "image": img,
                        "positions": [[pn + 1, int(left), int(right), int(top), int(bott)]],
                    },
                )

        for b in self.boxes:
            b["position_tag"] = self._line_tag(b, zoomin)
            b["image"] = self.crop(b["position_tag"], zoomin)
            b["positions"] = [[pos[0][-1] + 1, *pos[1:]] for pos in RAGPdfParser.extract_positions(b["position_tag"])]

        insert_table_figures(tbls, "table")
        insert_table_figures(figs, "figure")
        if callback:
            callback(1, "Structured ({:.2f}s)".format(timer() - start))
        return deepcopy(self.boxes)

    @staticmethod
    def remove_tag(txt):
        return re.sub(r"@@[\t0-9.-]+?##", "", txt)

    @staticmethod
    def extract_positions(txt):
        poss = []
        for tag in re.findall(r"@@[0-9-]+\t[0-9.\t]+##", txt):
            pn, left, right, top, bottom = tag.strip("#").strip("@").split("\t")
            left, right, top, bottom = float(left), float(right), float(top), float(bottom)
            poss.append(([int(p) - 1 for p in pn.split("-")], left, right, top, bottom))
        return poss

    def crop(self, text, ZM=3, need_position=False):
        imgs = []
        poss = self.extract_positions(text)
        if not poss:
            if need_position:
                return None, None
            return

        max_width = max(np.max([right - left for (_, left, right, _, _) in poss]), 6)
        GAP = 6
        pos = poss[0]
        poss.insert(0, ([pos[0][0]], pos[1], pos[2], max(0, pos[3] - 120), max(pos[3] - GAP, 0)))
        pos = poss[-1]
        poss.append(([pos[0][-1]], pos[1], pos[2], min(self.page_images[pos[0][-1]].size[1] / ZM, pos[4] + GAP), min(self.page_images[pos[0][-1]].size[1] / ZM, pos[4] + 120)))

        positions = []
        for ii, (pns, left, right, top, bottom) in enumerate(poss):
            right = left + max_width
            bottom *= ZM
            for pn in pns[1:]:
                bottom += self.page_images[pn - 1].size[1]
            imgs.append(self.page_images[pns[0]].crop((left * ZM, top * ZM, right * ZM, min(bottom, self.page_images[pns[0]].size[1]))))
            if 0 < ii < len(poss) - 1:
                positions.append((pns[0] + self.page_from, left, right, top, min(bottom, self.page_images[pns[0]].size[1]) / ZM))
            bottom -= self.page_images[pns[0]].size[1]
            for pn in pns[1:]:
                imgs.append(self.page_images[pn].crop((left * ZM, 0, right * ZM, min(bottom, self.page_images[pn].size[1]))))
                if 0 < ii < len(poss) - 1:
                    positions.append((pn + self.page_from, left, right, 0, min(bottom, self.page_images[pn].size[1]) / ZM))
                bottom -= self.page_images[pn].size[1]

        if not imgs:
            if need_position:
                return None, None
            return
        height = 0
        for img in imgs:
            height += img.size[1] + GAP
        height = int(height)
        width = int(np.max([i.size[0] for i in imgs]))
        pic = Image.new("RGB", (width, height), (245, 245, 245))
        height = 0
        for ii, img in enumerate(imgs):
            if ii == 0 or ii + 1 == len(imgs):
                img = img.convert("RGBA")
                overlay = Image.new("RGBA", img.size, (0, 0, 0, 0))
                overlay.putalpha(128)
                img = Image.alpha_composite(img, overlay).convert("RGB")
            pic.paste(img, (0, int(height)))
            height += img.size[1] + GAP

        if need_position:
            return pic, positions
        return pic

    def get_position(self, bx, ZM):
        poss = []
        pn = bx["page_number"]
        top = bx["top"] - self.page_cum_height[pn - 1]
        bott = bx["bottom"] - self.page_cum_height[pn - 1]
        poss.append((pn, bx["x0"], bx["x1"], top, min(bott, self.page_images[pn - 1].size[1] / ZM)))
        while bott * ZM > self.page_images[pn - 1].size[1]:
            bott -= self.page_images[pn - 1].size[1] / ZM
            top = 0
            pn += 1
            poss.append((pn, bx["x0"], bx["x1"], top, min(bott, self.page_images[pn - 1].size[1] / ZM)))
        return poss


class PlainParser:
    def __call__(self, filename, from_page=0, to_page=100000, **kwargs):
        self.outlines = []
        lines = []
        try:
            self.pdf = pdf2_read(filename if isinstance(filename, str) else BytesIO(filename))
            for page in self.pdf.pages[from_page:to_page]:
                lines.extend([t for t in page.extract_text().split("\n")])

            outlines = self.pdf.outline

            def dfs(arr, depth):
                for a in arr:
                    if isinstance(a, dict):
                        self.outlines.append((a["/Title"], depth))
                        continue
                    dfs(a, depth + 1)

            dfs(outlines, 0)
        except Exception:
            logging.exception("Outlines exception")
        if not self.outlines:
            logging.warning("Miss outlines")

        return [(line, "") for line in lines], []

    def crop(self, ck, need_position):
        raise NotImplementedError

    @staticmethod
    def remove_tag(txt):
        raise NotImplementedError


class VisionParser(RAGPdfParser):
    def __init__(self, vision_model, *args, **kwargs):
        super().__init__(*args, **kwargs)
        self.vision_model = vision_model

    def __images__(self, fnm, zoomin=3, page_from=0, page_to=299, callback=None):
        try:
            with sys.modules[LOCK_KEY_pdfplumber]:
                self.pdf = pdfplumber.open(fnm) if isinstance(fnm, str) else pdfplumber.open(BytesIO(fnm))
                self.page_images = [p.to_image(resolution=72 * zoomin).annotated for i, p in enumerate(self.pdf.pages[page_from:page_to])]
                self.total_page = len(self.pdf.pages)
        except Exception:
            self.page_images = None
            self.total_page = 0
            logging.exception("VisionParser __images__")

    def __call__(self, filename, from_page=0, to_page=100000, **kwargs):
        callback = kwargs.get("callback", lambda prog, msg: None)
        zoomin = kwargs.get("zoomin", 3)
        self.__images__(fnm=filename, zoomin=zoomin, page_from=from_page, page_to=to_page, callback=callback)

        total_pdf_pages = self.total_page

        start_page = max(0, from_page)
        end_page = min(to_page, total_pdf_pages)

        all_docs = []

        for idx, img_binary in enumerate(self.page_images or []):
            pdf_page_num = idx  # 0-based
            if pdf_page_num < start_page or pdf_page_num >= end_page:
                continue

            text = picture_vision_llm_chunk(
                binary=img_binary,
                vision_model=self.vision_model,
                prompt=vision_llm_describe_prompt(page=pdf_page_num + 1),
                callback=callback,
            )

            if kwargs.get("callback"):
                kwargs["callback"](idx * 1.0 / len(self.page_images), f"Processed: {idx + 1}/{len(self.page_images)}")

            if text:
                width, height = self.page_images[idx].size
                all_docs.append((
                    text,
                    f"@@{pdf_page_num + 1}\t{0.0:.1f}\t{width / zoomin:.1f}\t{0.0:.1f}\t{height / zoomin:.1f}##"
                ))
        return all_docs, []


if __name__ == "__main__":
    pass
