# -*- coding: utf-8 -*-
import os
import time
from dectris import albula
from PyQt4 import QtCore
from PyQt4.QtCore import SIGNAL, QThread, QMutex

class LiveView(QThread):
    FILETYPE_CBF = 0
    FILETYPE_TIF = 1
    FILETYPE_HDF5 = 2

    alive = False
    path = ""
    filetype = 0
    interval = 0.5 #s
    stoptimer = -1.0

    viewer = None
    subframe = None
    mutex = None

    def __init__(self, path=None, filetype=None, interval=None, parent=None):
        QThread.__init__(self, parent)
        if path is not None:
            self.path = path
        if filetype is not None:
            self.filetype = filetype
        if interval is not None:
            self.interval = interval
        self.mutex = QMutex()


    def start(self, path=None, filetype=None, interval=None):
        if path is not None:
            self.path = path
        if filetype is not None:
            self.filetype = filetype
        if interval is not None:
            self.interval = interval
        QThread.start(self)

    def stop(self, interval=0.0):
        if self.stoptimer < 0.0 and interval > 0.0:
            print "Live view thread: Stopping in %d seconds"%interval
            self.stoptimer = interval
            return
        print "Live view thread: Stopping thread"
        self.alive = False
        self.wait() # waits until run stops on his own

    def run(self):
        self.alive = True
        print "Live view thread: started"
        suffix = [".cbf", ".tif", ".hdf5"]

        if self.filetype in [LiveView.FILETYPE_CBF, LiveView.FILETYPE_TIF]:
            # open viewer
            while self.alive:
                # find latest image
                self.mutex.lock()
                files = [(os.path.getmtime(self.path + "/" + fn), fn)
                    for fn in os.listdir(self.path) if fn.lower().endswith(suffix[self.filetype])]
                files.sort()
                files.reverse()
                if len(files) > 0:
                    # display image
                    # wait to make sure the image is copied completely before displaying it
                    time.sleep(0.1)
                    try:
                        self.subframe.loadFile(self.path + "/" + files[0][1])
                    # viewer or subframe has been closed by the user
                    except:
                        self.mutex.unlock()
                        time.sleep(0.1)
                        try:
                            self.subframe =  self.viewer.openSubFrame()
                        except:
                            self.viewer = albula.openMainFrame()
                            self.subframe = self.viewer.openSubFrame()
                        continue
                self.mutex.unlock()
                # wait interval
                interval = 0.0
                while interval < self.interval and self.alive:
                    if self.stoptimer > 0.0:
                        self.stoptimer -= 0.05
                        if self.stoptimer < 0.0:
                            self.stoptimer = -1.0
                            self.alive = False
                    time.sleep(0.05)
                    interval += 0.05
        elif self.filetype == LiveView.FILETYPE_HDF5:
            print "Live view thread: HDF5 not supported yet"

        print "Live view thread: Thread for Live view died"
        self.alive = False

    def setPath(self, path=None):
        self.mutex.lock()
        if path is not None:
            self.path = path
        self.mutex.unlock()

    def setFiletype(self, filetype=None):
        restart = False
        if self.alive:
            restart = True
            self.stop()
        if filetype is not None:
            self.filetype = filetype
        if restart:
            self.start()

    def setInterval(self, interval=None):
        if interval is not None:
            self.interval = interval