import sys

import numpy as np
import time
import torch
from ..pytorchocr.base_ocr_v20 import BaseOCRV20
from . import pytorchocr_utility as utility
from ..pytorchocr.data import create_operators, transform
from ..pytorchocr.postprocess import build_post_process


class TextDetector(BaseOCRV20):
    def __init__(self, args, **kwargs):
        self.args = args
        self.det_algorithm = args.det_algorithm
        self.device = args.device
        pre_process_list = [{
            'DetResizeForTest': {
                'limit_side_len': args.det_limit_side_len,
                'limit_type': args.det_limit_type,
            }
        }, {
            'NormalizeImage': {
                'std': [0.229, 0.224, 0.225],
                'mean': [0.485, 0.456, 0.406],
                'scale': '1./255.',
                'order': 'hwc'
            }
        }, {
            'ToCHWImage': None
        }, {
            'KeepKeys': {
                'keep_keys': ['image', 'shape']
            }
        }]
        postprocess_params = {}
        if self.det_algorithm == "DB":
            postprocess_params['name'] = 'DBPostProcess'
            postprocess_params["thresh"] = args.det_db_thresh
            postprocess_params["box_thresh"] = args.det_db_box_thresh
            postprocess_params["max_candidates"] = 1000
            postprocess_params["unclip_ratio"] = args.det_db_unclip_ratio
            postprocess_params["use_dilation"] = args.use_dilation
            postprocess_params["score_mode"] = args.det_db_score_mode
        elif self.det_algorithm == "DB++":
            postprocess_params['name'] = 'DBPostProcess'
            postprocess_params["thresh"] = args.det_db_thresh
            postprocess_params["box_thresh"] = args.det_db_box_thresh
            postprocess_params["max_candidates"] = 1000
            postprocess_params["unclip_ratio"] = args.det_db_unclip_ratio
            postprocess_params["use_dilation"] = args.use_dilation
            postprocess_params["score_mode"] = args.det_db_score_mode
            pre_process_list[1] = {
                'NormalizeImage': {
                    'std': [1.0, 1.0, 1.0],
                    'mean':
                        [0.48109378172549, 0.45752457890196, 0.40787054090196],
                    'scale': '1./255.',
                    'order': 'hwc'
                }
            }
        elif self.det_algorithm == "EAST":
            postprocess_params['name'] = 'EASTPostProcess'
            postprocess_params["score_thresh"] = args.det_east_score_thresh
            postprocess_params["cover_thresh"] = args.det_east_cover_thresh
            postprocess_params["nms_thresh"] = args.det_east_nms_thresh
        elif self.det_algorithm == "SAST":
            pre_process_list[0] = {
                'DetResizeForTest': {
                    'resize_long': args.det_limit_side_len
                }
            }
            postprocess_params['name'] = 'SASTPostProcess'
            postprocess_params["score_thresh"] = args.det_sast_score_thresh
            postprocess_params["nms_thresh"] = args.det_sast_nms_thresh
            self.det_sast_polygon = args.det_sast_polygon
            if self.det_sast_polygon:
                postprocess_params["sample_pts_num"] = 6
                postprocess_params["expand_scale"] = 1.2
                postprocess_params["shrink_ratio_of_width"] = 0.2
            else:
                postprocess_params["sample_pts_num"] = 2
                postprocess_params["expand_scale"] = 1.0
                postprocess_params["shrink_ratio_of_width"] = 0.3
        elif self.det_algorithm == "PSE":
            postprocess_params['name'] = 'PSEPostProcess'
            postprocess_params["thresh"] = args.det_pse_thresh
            postprocess_params["box_thresh"] = args.det_pse_box_thresh
            postprocess_params["min_area"] = args.det_pse_min_area
            postprocess_params["box_type"] = args.det_pse_box_type
            postprocess_params["scale"] = args.det_pse_scale
            self.det_pse_box_type = args.det_pse_box_type
        elif self.det_algorithm == "FCE":
            pre_process_list[0] = {
                'DetResizeForTest': {
                    'rescale_img': [1080, 736]
                }
            }
            postprocess_params['name'] = 'FCEPostProcess'
            postprocess_params["scales"] = args.scales
            postprocess_params["alpha"] = args.alpha
            postprocess_params["beta"] = args.beta
            postprocess_params["fourier_degree"] = args.fourier_degree
            postprocess_params["box_type"] = args.det_fce_box_type
        else:
            print("unknown det_algorithm:{}".format(self.det_algorithm))
            sys.exit(0)

        self.preprocess_op = create_operators(pre_process_list)
        self.postprocess_op = build_post_process(postprocess_params)

        self.weights_path = args.det_model_path
        self.yaml_path = args.det_yaml_path
        network_config = utility.get_arch_config(self.weights_path)
        super(TextDetector, self).__init__(network_config, **kwargs)
        self.load_pytorch_weights(self.weights_path)
        self.net.eval()
        self.net.to(self.device)
        for module in self.net.modules():
            if hasattr(module, 'rep'):
                module.rep()

    def _batch_process_same_size(self, img_list):
        """
            对相同尺寸的图像进行批处理

            Args:
                img_list: 相同尺寸的图像列表

            Returns:
                batch_results: 批处理结果列表
                total_elapse: 总耗时
            """
        starttime = time.time()

        # 预处理所有图像
        batch_data = []
        batch_shapes = []
        ori_imgs = []

        for img in img_list:
            ori_im = img.copy()
            ori_imgs.append(ori_im)

            data = {'image': img}
            data = transform(data, self.preprocess_op)
            if data is None:
                # 如果预处理失败，返回空结果
                return [(None, 0) for _ in img_list], 0

            img_processed, shape_list = data
            batch_data.append(img_processed)
            batch_shapes.append(shape_list)

        # 堆叠成批处理张量
        try:
            batch_tensor = np.stack(batch_data, axis=0)
            batch_shapes = np.stack(batch_shapes, axis=0)
        except Exception as e:
            # 如果堆叠失败，回退到逐个处理
            batch_results = []
            for img in img_list:
                dt_boxes, elapse = self.__call__(img)
                batch_results.append((dt_boxes, elapse))
            return batch_results, time.time() - starttime

        # 批处理推理
        with torch.no_grad():
            inp = torch.from_numpy(batch_tensor)
            inp = inp.to(self.device)
            outputs = self.net(inp)

        # 处理输出
        preds = {}
        if self.det_algorithm == "EAST":
            preds['f_geo'] = outputs['f_geo'].cpu().numpy()
            preds['f_score'] = outputs['f_score'].cpu().numpy()
        elif self.det_algorithm == 'SAST':
            preds['f_border'] = outputs['f_border'].cpu().numpy()
            preds['f_score'] = outputs['f_score'].cpu().numpy()
            preds['f_tco'] = outputs['f_tco'].cpu().numpy()
            preds['f_tvo'] = outputs['f_tvo'].cpu().numpy()
        elif self.det_algorithm in ['DB', 'PSE', 'DB++']:
            preds['maps'] = outputs['maps'].cpu().numpy()
        elif self.det_algorithm == 'FCE':
            for i, (k, output) in enumerate(outputs.items()):
                preds['level_{}'.format(i)] = output.cpu().numpy()
        else:
            raise NotImplementedError

        # 后处理每个图像的结果
        batch_results = []
        total_elapse = time.time() - starttime

        for i in range(len(img_list)):
            # 提取单个图像的预测结果
            single_preds = {}
            for key, value in preds.items():
                if isinstance(value, np.ndarray):
                    single_preds[key] = value[i:i + 1]  # 保持批次维度
                else:
                    single_preds[key] = value

            # 后处理
            post_result = self.postprocess_op(single_preds, batch_shapes[i:i + 1])
            dt_boxes = post_result[0]['points']

            # 过滤和裁剪检测框
            if (self.det_algorithm == "SAST" and
                self.det_sast_polygon) or (self.det_algorithm in ["PSE", "FCE"] and
                                           self.postprocess_op.box_type == 'poly'):
                dt_boxes = self.filter_tag_det_res_only_clip(dt_boxes, ori_imgs[i].shape)
            else:
                dt_boxes = self.filter_tag_det_res(dt_boxes, ori_imgs[i].shape)

            batch_results.append((dt_boxes, total_elapse / len(img_list)))

        return batch_results, total_elapse

    def batch_predict(self, img_list, max_batch_size=8):
        """
        批处理预测方法，支持多张图像同时检测

        Args:
            img_list: 图像列表
            max_batch_size: 最大批处理大小

        Returns:
            batch_results: 批处理结果列表，每个元素为(dt_boxes, elapse)
        """
        if not img_list:
            return []

        batch_results = []

        # 分批处理
        for i in range(0, len(img_list), max_batch_size):
            batch_imgs = img_list[i:i + max_batch_size]
            # assert尺寸一致
            batch_dt_boxes, batch_elapse = self._batch_process_same_size(batch_imgs)
            batch_results.extend(batch_dt_boxes)

        return batch_results

    def order_points_clockwise(self, pts):
        """
        reference from: https://github.com/jrosebr1/imutils/blob/master/imutils/perspective.py
        # sort the points based on their x-coordinates
        """
        xSorted = pts[np.argsort(pts[:, 0]), :]

        # grab the left-most and right-most points from the sorted
        # x-roodinate points
        leftMost = xSorted[:2, :]
        rightMost = xSorted[2:, :]

        # now, sort the left-most coordinates according to their
        # y-coordinates so we can grab the top-left and bottom-left
        # points, respectively
        leftMost = leftMost[np.argsort(leftMost[:, 1]), :]
        (tl, bl) = leftMost

        rightMost = rightMost[np.argsort(rightMost[:, 1]), :]
        (tr, br) = rightMost

        rect = np.array([tl, tr, br, bl], dtype="float32")
        return rect

    def clip_det_res(self, points, img_height, img_width):
        for pno in range(points.shape[0]):
            points[pno, 0] = int(min(max(points[pno, 0], 0), img_width - 1))
            points[pno, 1] = int(min(max(points[pno, 1], 0), img_height - 1))
        return points

    def filter_tag_det_res(self, dt_boxes, image_shape):
        img_height, img_width = image_shape[0:2]
        dt_boxes_new = []
        for box in dt_boxes:
            box = self.order_points_clockwise(box)
            box = self.clip_det_res(box, img_height, img_width)
            rect_width = int(np.linalg.norm(box[0] - box[1]))
            rect_height = int(np.linalg.norm(box[0] - box[3]))
            if rect_width <= 3 or rect_height <= 3:
                continue
            dt_boxes_new.append(box)
        dt_boxes = np.array(dt_boxes_new)
        return dt_boxes

    def filter_tag_det_res_only_clip(self, dt_boxes, image_shape):
        img_height, img_width = image_shape[0:2]
        dt_boxes_new = []
        for box in dt_boxes:
            box = self.clip_det_res(box, img_height, img_width)
            dt_boxes_new.append(box)
        dt_boxes = np.array(dt_boxes_new)
        return dt_boxes

    def __call__(self, img):
        ori_shape = img.shape
        data = {'image': img}
        data = transform(data, self.preprocess_op)
        img, shape_list = data
        if img is None:
            return None, 0
        img = np.expand_dims(img, axis=0)
        shape_list = np.expand_dims(shape_list, axis=0)
        img = img.copy()
        starttime = time.time()

        with torch.no_grad():
            inp = torch.from_numpy(img)
            inp = inp.to(self.device)
            outputs = self.net(inp)

        preds = {}
        if self.det_algorithm == "EAST":
            preds['f_geo'] = outputs['f_geo'].cpu().numpy()
            preds['f_score'] = outputs['f_score'].cpu().numpy()
        elif self.det_algorithm == 'SAST':
            preds['f_border'] = outputs['f_border'].cpu().numpy()
            preds['f_score'] = outputs['f_score'].cpu().numpy()
            preds['f_tco'] = outputs['f_tco'].cpu().numpy()
            preds['f_tvo'] = outputs['f_tvo'].cpu().numpy()
        elif self.det_algorithm in ['DB', 'PSE', 'DB++']:
            preds['maps'] = outputs['maps'].cpu().numpy()
        elif self.det_algorithm == 'FCE':
            for i, (k, output) in enumerate(outputs.items()):
                preds['level_{}'.format(i)] = output
        else:
            raise NotImplementedError

        post_result = self.postprocess_op(preds, shape_list)
        dt_boxes = post_result[0]['points']
        if (self.det_algorithm == "SAST" and
            self.det_sast_polygon) or (self.det_algorithm in ["PSE", "FCE"] and
                                       self.postprocess_op.box_type == 'poly'):
            dt_boxes = self.filter_tag_det_res_only_clip(dt_boxes, ori_shape)
        else:
            dt_boxes = self.filter_tag_det_res(dt_boxes, ori_shape)

        elapse = time.time() - starttime
        return dt_boxes, elapse