import sys
import tarfile
import os
import time
import datetime
import functools 
import cv2
import platform
import numpy as np
import fitz
from PIL import Image
from pdf2docx.converter import Converter
from qtpy.QtWidgets import QApplication, QWidget, QPushButton, QProgressBar, \
                           QGridLayout, QMessageBox, QLabel, QFileDialog, QCheckBox
from qtpy.QtCore import Signal, QThread, QObject
from qtpy.QtGui import QImage, QPixmap, QIcon

file = os.path.dirname(os.path.abspath(__file__))
root = os.path.abspath(os.path.join(file, '../../'))
sys.path.append(file)
sys.path.insert(0, root)


from ppstructure.predict_system import StructureSystem, save_structure_res
from ppstructure.utility import parse_args, draw_structure_result
from ppocr.utils.network import download_with_progressbar
from ppstructure.recovery.recovery_to_doc import sorted_layout_boxes, convert_info_docx
# from ScreenShotWidget import ScreenShotWidget

__APPNAME__ = "pdf2word"
__VERSION__ = "0.2.2"

URLs_EN = {
    # 下载超英文轻量级PP-OCRv3模型的检测模型并解压
    "en_PP-OCRv3_det_infer": "https://paddleocr.bj.bcebos.com/PP-OCRv3/english/en_PP-OCRv3_det_infer.tar",
    # 下载英文轻量级PP-OCRv3模型的识别模型并解压
    "en_PP-OCRv3_rec_infer": "https://paddleocr.bj.bcebos.com/PP-OCRv3/english/en_PP-OCRv3_rec_infer.tar",
    # 下载超轻量级英文表格英文模型并解压
    "en_ppstructure_mobile_v2.0_SLANet_infer": "https://paddleocr.bj.bcebos.com/ppstructure/models/slanet/en_ppstructure_mobile_v2.0_SLANet_infer.tar",
    # 英文版面分析模型
    "picodet_lcnet_x1_0_fgd_layout_infer": "https://paddleocr.bj.bcebos.com/ppstructure/models/layout/picodet_lcnet_x1_0_fgd_layout_infer.tar",
}
DICT_EN = {
    "rec_char_dict_path": "en_dict.txt",
    "layout_dict_path": "layout_publaynet_dict.txt",
}

URLs_CN = {
    # 下载超中文轻量级PP-OCRv3模型的检测模型并解压
    "cn_PP-OCRv3_det_infer": "https://paddleocr.bj.bcebos.com/PP-OCRv3/chinese/ch_PP-OCRv3_det_infer.tar",
    # 下载中文轻量级PP-OCRv3模型的识别模型并解压
    "cn_PP-OCRv3_rec_infer": "https://paddleocr.bj.bcebos.com/PP-OCRv3/chinese/ch_PP-OCRv3_rec_infer.tar",
    # 下载超轻量级英文表格英文模型并解压
    "cn_ppstructure_mobile_v2.0_SLANet_infer": "https://paddleocr.bj.bcebos.com/ppstructure/models/slanet/en_ppstructure_mobile_v2.0_SLANet_infer.tar",
    # 中文版面分析模型
    "picodet_lcnet_x1_0_fgd_layout_cdla_infer": "https://paddleocr.bj.bcebos.com/ppstructure/models/layout/picodet_lcnet_x1_0_fgd_layout_cdla_infer.tar",
}
DICT_CN = {
    "rec_char_dict_path":  "ppocr_keys_v1.txt",
    "layout_dict_path": "layout_cdla_dict.txt",
}



def QImageToCvMat(incomingImage) -> np.array:
    '''  
    Converts a QImage into an opencv MAT format  
    '''

    incomingImage = incomingImage.convertToFormat(QImage.Format.Format_RGBA8888)

    width = incomingImage.width()
    height = incomingImage.height()

    ptr = incomingImage.bits()
    ptr.setsize(height * width * 4)
    arr = np.frombuffer(ptr, np.uint8).reshape((height, width, 4))
    return arr


def readImage(image_file) -> list:
    if os.path.basename(image_file)[-3:] == 'pdf':
        imgs = []
        with fitz.open(image_file) as pdf:
            for pg in range(0, pdf.pageCount):
                page = pdf[pg]
                mat = fitz.Matrix(2, 2)
                pm = page.getPixmap(matrix=mat, alpha=False)

                # if width or height > 2000 pixels, don't enlarge the image
                if pm.width > 2000 or pm.height > 2000:
                    pm = page.getPixmap(matrix=fitz.Matrix(1, 1), alpha=False)

                img = Image.frombytes("RGB", [pm.width, pm.height], pm.samples)
                img = cv2.cvtColor(np.array(img), cv2.COLOR_RGB2BGR)
                imgs.append(img)
    else:
        img = cv2.imread(image_file, cv2.IMREAD_COLOR)
        if img is not None:
            imgs = [img]
    
    return imgs


class Worker(QThread):
    progressBarValue = Signal(int)
    progressBarRange = Signal(int)
    endsignal = Signal()
    exceptedsignal = Signal(str) #发送一个异常信号
    loopFlag = True

    def __init__(self, predictors, save_pdf, vis_font_path, use_pdf2docx_api):
        super(Worker, self).__init__()
        self.predictors = predictors
        self.save_pdf = save_pdf
        self.vis_font_path = vis_font_path
        self.lang = 'EN'
        self.imagePaths = []
        self.use_pdf2docx_api = use_pdf2docx_api
        self.outputDir = None
        self.totalPageCnt = 0
        self.pageCnt = 0
        self.setStackSize(1024*1024)

    def setImagePath(self, imagePaths):
        self.imagePaths = imagePaths

    def setLang(self, lang):
        self.lang = lang

    def setOutputDir(self, outputDir):
        self.outputDir = outputDir
    
    def setPDFParser(self, enabled):
        self.use_pdf2docx_api = enabled

    def resetPageCnt(self):
        self.pageCnt = 0

    def resetTotalPageCnt(self):
        self.totalPageCnt = 0

    def ppocrPrecitor(self, imgs, img_name):
        all_res = []
        # update progress bar ranges
        self.totalPageCnt += len(imgs)
        self.progressBarRange.emit(self.totalPageCnt)
        # processing pages
        for index, img in enumerate(imgs):
            res, time_dict = self.predictors[self.lang](img)

            # save output
            save_structure_res(res, self.outputDir, img_name)
            # draw_img = draw_structure_result(img, res, self.vis_font_path)
            # img_save_path = os.path.join(self.outputDir, img_name, 'show_{}.jpg'.format(index))
            # if res != []:
            #     cv2.imwrite(img_save_path, draw_img)

            # recovery
            h, w, _ = img.shape
            res = sorted_layout_boxes(res, w)
            all_res += res
            self.pageCnt += 1
            self.progressBarValue.emit(self.pageCnt)

        if all_res != []:
            try:
                convert_info_docx(imgs, all_res, self.outputDir, img_name)
            except Exception as ex:
                print("error in layout recovery image:{}, err msg: {}".
                    format(img_name, ex))
        print("Predict time : {:.3f}s".format(time_dict['all']))
        print('result save to {}'.format(self.outputDir)) 

    def run(self):
        self.resetPageCnt()
        self.resetTotalPageCnt()
        try:
            os.makedirs(self.outputDir, exist_ok=True)
            for i, image_file in enumerate(self.imagePaths):
                if not self.loopFlag:
                    break
                # using use_pdf2docx_api for PDF parsing
                if self.use_pdf2docx_api \
                    and os.path.basename(image_file)[-3:] == 'pdf':
                    self.totalPageCnt += 1
                    self.progressBarRange.emit(self.totalPageCnt)
                    print('===============using use_pdf2docx_api===============')
                    img_name = os.path.basename(image_file).split('.')[0]
                    docx_file = os.path.join(
                        self.outputDir, '{}.docx'.format(img_name))
                    cv = Converter(image_file)
                    cv.convert(docx_file)
                    cv.close()
                    print('docx save to {}'.format(docx_file))
                    self.pageCnt += 1
                    self.progressBarValue.emit(self.pageCnt)
                else:
                    # using PPOCR for PDF/Image parsing
                    imgs = readImage(image_file)
                    if len(imgs) == 0:
                        continue
                    img_name = os.path.basename(image_file).split('.')[0]
                    os.makedirs(os.path.join(self.outputDir, img_name), exist_ok=True)
                    self.ppocrPrecitor(imgs, img_name)
                # file processed
            self.endsignal.emit()
            # self.exec()
        except Exception as e:
            self.exceptedsignal.emit(str(e)) # 将异常发送给UI进程


class APP_Image2Doc(QWidget):
    def __init__(self):
        super().__init__()
        # self.setFixedHeight(100)
        # self.setFixedWidth(520)

        # settings
        self.imagePaths = []
        # self.screenShotWg = ScreenShotWidget()
        self.screenShot = None
        self.save_pdf = False
        self.output_dir = None
        self.vis_font_path = os.path.join(root,
                "doc", "fonts", "simfang.ttf")
        self.use_pdf2docx_api = False

        # ProgressBar
        self.pb = QProgressBar()
        self.pb.setRange(0, 100)
        self.pb.setValue(0)

        # 初始化界面
        self.setupUi()

        # 下载模型
        self.downloadModels(URLs_EN)
        self.downloadModels(URLs_CN)

        # 初始化模型
        predictors = { 
            'EN': self.initPredictor('EN'),
            'CN': self.initPredictor('CN'),
        }

        # 设置工作进程
        self._thread = Worker(predictors, self.save_pdf, self.vis_font_path, self.use_pdf2docx_api)
        self._thread.progressBarValue.connect(self.handleProgressBarUpdateSingal)
        self._thread.endsignal.connect(self.handleEndsignalSignal)
        # self._thread.finished.connect(QObject.deleteLater)
        self._thread.progressBarRange.connect(self.handleProgressBarRangeSingal)
        self._thread.exceptedsignal.connect(self.handleThreadException)
        self.time_start = 0  # save start time

    def setupUi(self):
        self.setObjectName("MainWindow")
        self.setWindowTitle(__APPNAME__ + " " + __VERSION__)

        layout = QGridLayout()

        self.openFileButton = QPushButton("打开文件")
        self.openFileButton.setIcon(QIcon(QPixmap("./icons/folder-plus.png")))
        layout.addWidget(self.openFileButton, 0, 0, 1, 1)
        self.openFileButton.clicked.connect(self.handleOpenFileSignal)

        # screenShotButton = QPushButton("截图识别")
        # layout.addWidget(screenShotButton, 0, 1, 1, 1)
        # screenShotButton.clicked.connect(self.screenShotSlot)
        # screenShotButton.setEnabled(False) # temporarily disenble

        self.startCNButton = QPushButton("中文转换")
        self.startCNButton.setIcon(QIcon(QPixmap("./icons/chinese.png")))
        layout.addWidget(self.startCNButton, 0, 1, 1, 1)
        self.startCNButton.clicked.connect(
            functools.partial(self.handleStartSignal, 'CN', False))

        self.startENButton = QPushButton("英文转换")
        self.startENButton.setIcon(QIcon(QPixmap("./icons/english.png")))
        layout.addWidget(self.startENButton, 0, 2, 1, 1)
        self.startENButton.clicked.connect(
            functools.partial(self.handleStartSignal, 'EN', False))

        self.PDFParserButton = QPushButton('PDF解析', self)
        layout.addWidget(self.PDFParserButton, 0, 3, 1, 1)
        self.PDFParserButton.clicked.connect(
            functools.partial(self.handleStartSignal, 'CN', True))
        
        self.showResultButton = QPushButton("显示结果")
        self.showResultButton.setIcon(QIcon(QPixmap("./icons/folder-open.png")))
        layout.addWidget(self.showResultButton, 0, 4, 1, 1)
        self.showResultButton.clicked.connect(self.handleShowResultSignal)

        # ProgressBar
        layout.addWidget(self.pb, 2, 0, 1, 5)
        # time estimate label
        self.timeEstLabel = QLabel(
            ("Time Left: --"))
        layout.addWidget(self.timeEstLabel, 3, 0, 1, 5)

        self.setLayout(layout)

    def downloadModels(self, URLs):
        # using custom model
        tar_file_name_list = [
            'inference.pdiparams', 
            'inference.pdiparams.info', 
            'inference.pdmodel',
            'model.pdiparams', 
            'model.pdiparams.info', 
            'model.pdmodel'
        ]
        model_path = os.path.join(root, 'inference')
        os.makedirs(model_path, exist_ok=True)

        # download and unzip models
        for name in URLs.keys():
            url = URLs[name]
            print("Try downloading file: {}".format(url))
            tarname = url.split('/')[-1]
            tarpath = os.path.join(model_path, tarname)
            if os.path.exists(tarpath):
                print("File have already exist. skip")
            else:
                try:
                    download_with_progressbar(url, tarpath)
                except Exception as e:
                    print("Error occurred when downloading file, error message:")
                    print(e)
            
            # unzip model tar
            try:
                with tarfile.open(tarpath, 'r') as tarObj:
                    storage_dir = os.path.join(model_path, name)
                    os.makedirs(storage_dir, exist_ok=True)
                    for member in tarObj.getmembers():
                        filename = None
                        for tar_file_name in tar_file_name_list:
                            if tar_file_name in member.name:
                                filename = tar_file_name
                        if filename is None:
                            continue
                        file = tarObj.extractfile(member)
                        with open(
                                os.path.join(storage_dir, filename),
                                'wb') as f:
                            f.write(file.read())
            except Exception as e:
                    print("Error occurred when unziping file, error message:")
                    print(e)

    def initPredictor(self, lang='EN'):
        # init predictor args
        args = parse_args()
        args.table_max_len = 488
        args.ocr = True
        args.recovery = True
        args.save_pdf = self.save_pdf
        args.table_char_dict_path = os.path.join(root, 
                "ppocr", "utils", "dict", "table_structure_dict.txt")
        if lang == 'EN':
            args.det_model_dir = os.path.join(root,  # 此处从这里找到模型存放位置
                "inference", "en_PP-OCRv3_det_infer")
            args.rec_model_dir = os.path.join(root, 
                "inference", "en_PP-OCRv3_rec_infer")
            args.table_model_dir = os.path.join(root, 
                "inference", "en_ppstructure_mobile_v2.0_SLANet_infer")
            args.output = os.path.join(root, "output") # 结果保存路径
            args.layout_model_dir = os.path.join(root,
                "inference", "picodet_lcnet_x1_0_fgd_layout_infer")
            lang_dict = DICT_EN
        elif lang == 'CN':
            args.det_model_dir = os.path.join(root,  # 此处从这里找到模型存放位置
                "inference", "cn_PP-OCRv3_det_infer")
            args.rec_model_dir = os.path.join(root, 
                "inference", "cn_PP-OCRv3_rec_infer")
            args.table_model_dir = os.path.join(root, 
                "inference", "cn_ppstructure_mobile_v2.0_SLANet_infer")
            args.output = os.path.join(root, "output") # 结果保存路径
            args.layout_model_dir = os.path.join(root,
                "inference", "picodet_lcnet_x1_0_fgd_layout_cdla_infer")
            lang_dict = DICT_CN
        else:
            raise ValueError("Unsupported language")
        args.rec_char_dict_path = os.path.join(root, 
                "ppocr", "utils", 
                lang_dict['rec_char_dict_path'])
        args.layout_dict_path = os.path.join(root,
                "ppocr", "utils", "dict", "layout_dict", 
                lang_dict['layout_dict_path'])
        # init predictor
        return StructureSystem(args)
    
    def handleOpenFileSignal(self):
        '''
        可以多选图像文件
        '''
        selectedFiles = QFileDialog.getOpenFileNames(self, 
            "多文件选择", "/", "图片文件 (*.png *.jpeg *.jpg *.bmp *.pdf)")[0]
        if len(selectedFiles) > 0:
            self.imagePaths = selectedFiles
            self.screenShot = None # discard screenshot temp image
            self.pb.setValue(0)

    # def screenShotSlot(self):
    #     '''
    #     选定图像文件和截图的转换过程只能同时进行一个
    #     截图只能同时转换一个
    #     '''
    #     self.screenShotWg.start()
    #     if self.screenShotWg.captureImage:
    #         self.screenShot = self.screenShotWg.captureImage
    #         self.imagePaths.clear() # discard openfile temp list
    #         self.pb.setRange(0, 1)
    #         self.pb.setValue(0)

    def handleStartSignal(self, lang='EN', pdfParser=False):
        if self.screenShot: # for screenShot
            img_name = 'screenshot_' + time.strftime("%Y%m%d%H%M%S", time.localtime())
            image = QImageToCvMat(self.screenShot)
            self.predictAndSave(image, img_name, lang)
            # update Progress Bar
            self.pb.setValue(1)
            QMessageBox.information(self, 
                u'Information', "文档提取完成")
        elif len(self.imagePaths) > 0 : # for image file selection
            # Must set image path list and language before start
            self.output_dir = os.path.join(
                os.path.dirname(self.imagePaths[0]), "output")  # output_dir shold be same as imagepath
            self._thread.setOutputDir(self.output_dir)
            self._thread.setImagePath(self.imagePaths)
            self._thread.setLang(lang)
            self._thread.setPDFParser(pdfParser)
            # disenble buttons
            self.openFileButton.setEnabled(False)
            self.startCNButton.setEnabled(False)
            self.startENButton.setEnabled(False)
            self.PDFParserButton.setEnabled(False)
            # 启动工作进程
            self._thread.start()
            self.time_start = time.time() # log start time
            QMessageBox.information(self, 
                u'Information', "开始转换")
        else:
            QMessageBox.warning(self, 
                u'Information', "请选择要识别的文件或截图")

    def handleShowResultSignal(self):
        if self.output_dir is None:
            return
        if os.path.exists(self.output_dir):
            if platform.system() == 'Windows':
                os.startfile(self.output_dir)
            else:
                os.system('open ' + os.path.normpath(self.output_dir))
        else:
            QMessageBox.information(self, 
                u'Information', "输出文件不存在")

    def handleProgressBarUpdateSingal(self, i):
        self.pb.setValue(i)
        # calculate time left of recognition
        lenbar = self.pb.maximum()
        avg_time = (time.time() - self.time_start) / i  # Use average time to prevent time fluctuations
        time_left = str(datetime.timedelta(seconds=avg_time * (lenbar - i))).split(".")[0]  # Remove microseconds
        self.timeEstLabel.setText(f"Time Left: {time_left}")  # show time left

    def handleProgressBarRangeSingal(self, max):
        self.pb.setRange(0, max)

    def handleEndsignalSignal(self):
        # enble buttons
        self.openFileButton.setEnabled(True)
        self.startCNButton.setEnabled(True)
        self.startENButton.setEnabled(True)
        self.PDFParserButton.setEnabled(True)
        QMessageBox.information(self, u'Information', "转换结束")

    def handleCBChangeSignal(self):
        self._thread.setPDFParser(self.checkBox.isChecked())

    def handleThreadException(self, message):
        self._thread.quit()
        QMessageBox.information(self, 'Error', message)


def main():
    app = QApplication(sys.argv)

    window = APP_Image2Doc()  # 创建对象
    window.show()  # 全屏显示窗口

    QApplication.processEvents()
    sys.exit(app.exec())


if __name__ == "__main__":
    main()
