import multiprocessing
import os
import tempfile
import time
from typing import Optional

from PyQt6.QtCore import QRunnable, QThread, QThreadPool
from PyQt6.QtWidgets import QWidget, QVBoxLayout, QHBoxLayout, QLineEdit, QCheckBox

from bigtext import BigText
from logFileModel import LogFileModel
import asyncio

class FilterTask(QRunnable):

    aborted = False
    future : asyncio.Future

    def __init__(self, source_model: LogFileModel, filter_model: LogFileModel, query: str):
        super(FilterTask, self).__init__()
        self.source_model = source_model
        self.filter_model = filter_model
        self.query = query
        self.future = asyncio.Future()

    def run(self):
        #print("writing to tmp file", self.filter_model.get_file())
        start = time.time()
        self.filter_model.truncate()
        with open(self.source_model.get_file(), "rb") as source:
            while l := source.readline():
                line = l.decode("utf8", errors="ignore")
                #print(line)
                if line.find(self.query) >= 0:
                    self.filter_model.write_line(line)

                if self.aborted or self.future.cancelled():
                    print("aborted")
                    break
        print("filtering for %s took %s" % (self.query, time.time() - start) )
        self.future.done()

class FilterWidget(QWidget):
    future = None
    filter_model : LogFileModel
    filter_task :Optional[FilterTask] = None

    def __init__(self, source_model: LogFileModel):
        super(FilterWidget, self).__init__()
        self.source_model = source_model

        self.layout = QVBoxLayout(self)
        self.layout.setContentsMargins(0, 0, 0, 0)

        query_field = QLineEdit()
        query_field.textChanged.connect(self.query_changed)

        ignore_case = QCheckBox(self.tr("ignore case"))
        ignore_case.setChecked(True)

        is_regex = QCheckBox(self.tr("regex"))
        is_regex.setChecked(True)

        filter_bar = QWidget()
        filter_bar.layout = QHBoxLayout(filter_bar)
        filter_bar.layout.setContentsMargins(0, 0, 0, 0)
        filter_bar.layout.addWidget(query_field)
        filter_bar.layout.addWidget(ignore_case)
        filter_bar.layout.addWidget(is_regex)

        (_handle, self.tmpfilename) = tempfile.mkstemp()
        self.filter_model = LogFileModel(self.tmpfilename, self.source_model.settings)
        self.hits_view = BigText(self.filter_model)

        self.layout.addWidget(filter_bar)
        self.layout.addWidget(self.hits_view)

    def query_changed(self, query: str):
        if len(query) == 0:
            return

        print("start function")
        if self.filter_task:
            print("abort started ", time.time())
            self.filter_task.aborted = True
            print("abort done    ", time.time())

        self.filter_task = FilterTask(self.source_model, self.filter_model, query)
        # QThreadPool takes ownership and deletes 'hello' automatically
        QThreadPool.globalInstance().start(self.filter_task)