from PyQt5.QtWidgets import *
from PyQt5.QtGui import *
from PyQt5.QtCore import *
import sys
import os
import PyPDF2  # PDF操作庫

finished = pyqtSignal(bool)

class WorkThread(QThread):
    finished = pyqtSignal(bool)

    def __init__(self, parent=None):
        super(WorkThread, self).__init__(parent)
        self.parent = parent
        self.working = True

    def __del__(self):
        self.working = False
        self.wait()

    def run(self):
        pdf_files_path = self.parent.pdf_files_path.text().strip()
        pdf_tar_dir = self.parent.pdf_tar_dir.text().strip()

        file_list = pdf_files_path.split(',')

        merge = PyPDF2.PdfFileMerger()
        for file in file_list:
            merge.append(PyPDF2.PdfFileReader(file))
        merge.write(pdf_tar_dir + '/匯總.pdf')

        self.finished.emit(True)

class PDFMerge(QWidget):
    def __init__(self):
        super(PDFMerge, self).__init__()
        self.init_ui()

    def init_ui(self):
        self.setWindowTitle('PDF文件合并器  公眾號(hào)：[Python 集中營]')
        self.setWindowIcon(QIcon('pdf.ico'))
        self.setFixedWidth(500)
        self.setFixedHeight(120)

        grid = QGridLayout()

        self.pdf_files_path = QLineEdit()
        self.pdf_files_path.setReadOnly(True)

        self.pdf_files_btn = QPushButton()
        self.pdf_files_btn.setText('源文件')
        self.pdf_files_btn.clicked.connect(self.pdf_files_btn_click)

        self.pdf_tar_dir = QLineEdit()
        self.pdf_tar_dir.setReadOnly(True)

        self.pdf_tar_btn = QPushButton()
        self.pdf_tar_btn.setText('目標(biāo)路徑')
        self.pdf_tar_btn.clicked.connect(self.pdf_tar_btn_click)

        self.start_btn = QPushButton()
        self.start_btn.setText('開始合并吧')
        self.start_btn.clicked.connect(self.start_btn_click)

        grid.addWidget(self.pdf_files_path, 0, 0, 1, 1)
        grid.addWidget(self.pdf_files_btn, 0, 1, 1, 1)

        grid.addWidget(self.pdf_tar_dir, 1, 0, 1, 1)
        grid.addWidget(self.pdf_tar_btn, 1, 1, 1, 1)

        grid.addWidget(self.start_btn, 2, 0, 1, 2)

        self.thread_ = WorkThread(self)
        self.thread_.finished.connect(self.finished)

        self.setLayout(grid)

    def pdf_files_btn_click(self):
        files = QFileDialog.getOpenFileNames(self, os.getcwd(), '打開文件', 'PDF Files(*.pdf)')
        file_list = files[0]
        self.pdf_files_path.setText(','.join(file_list))

    def pdf_tar_btn_click(self):
        dir = QFileDialog.getExistingDirectory(self, os.getcwd(), '打開文件夾')
        self.pdf_tar_dir.setText(dir)

    def start_btn_click(self):
        self.start_btn.setEnabled(False)
        self.thread_.start()

    def finished(self, finished):
        if finished is True:
            self.start_btn.setEnabled(True)

if __name__ == '__main__':
    app = QApplication(sys.argv)
    main = PDFMerge()
    main.show()
    sys.exit(app.exec_())