import sys
import json
import piexif

from . geo import decimal_to_dms

#from .error import print_error


class ExifEdit(object):

    def __init__(self, filename):
        """Initialize the object"""
        self._filename = filename
        self._ef = None
        try:
            self._ef = piexif.load(filename)
        except IOError:
            etype, value, traceback = sys.exc_info()
            print >> sys.stderr, "Error opening file:", value
        except ValueError:
            etype, value, traceback = sys.exc_info()
            print >> sys.stderr, "Error opening file:", value

    def add_image_description(self, dict):
        """Add a dict to image description."""
        if self._ef is not None:
            self._ef['0th'][piexif.ImageIFD.ImageDescription] = json.dumps(
                dict)

    def add_orientation(self, orientation):
        """Add image orientation to image."""
        if not orientation in range(1, 9):
            print(
                "Error value for orientation, value must be in range(1,9), setting to default 1")
            self._ef['0th'][piexif.ImageIFD.Orientation] = 1
        else:
            self._ef['0th'][piexif.ImageIFD.Orientation] = orientation

    def add_date_time_original(self, date_time):
        """Add date time original."""
        try:
            DateTimeOriginal = date_time.strftime('%Y:%m:%d %H:%M:%S')
            self._ef['Exif'][piexif.ExifIFD.DateTimeOriginal] = DateTimeOriginal
        except Exception as e:
            print("Error writing DateTimeOriginal, due to " + str(e))
                                                  
        if date_time.microsecond != 0:
            self.add_subsectimeoriginal(date_time.microsecond)
            
    def add_subsectimeoriginal(self, subsec_value):
        """Add subsecond value in the subsectimeoriginal exif tag"""
        try:
            subsec = str(subsec_value).zfill(6)
            self._ef['Exif'][piexif.ExifIFD.SubSecTimeOriginal] = subsec
        except Exception as e:
            print("Error writing SubSecTimeOriginal, due to " + str(e))

    def add_lat_lon(self, lat, lon, precision=1e7):
        """Add lat, lon to gps (lat, lon in float)."""
        self._ef["GPS"][piexif.GPSIFD.GPSLatitudeRef] = "N" if lat > 0 else "S"
        self._ef["GPS"][piexif.GPSIFD.GPSLongitudeRef] = "E" if lon > 0 else "W"
        self._ef["GPS"][piexif.GPSIFD.GPSLongitude] = decimal_to_dms(
            abs(lon), int(precision))
        self._ef["GPS"][piexif.GPSIFD.GPSLatitude] = decimal_to_dms(
            abs(lat), int(precision))

    def add_image_history(self, data):
        """Add arbitrary string to ImageHistory tag."""
        self._ef['0th'][piexif.ImageIFD.ImageHistory] = json.dumps(data)

    def add_camera_make_model(self, make, model):
        ''' Add camera make and model.'''
        self._ef['0th'][piexif.ImageIFD.Make] = make
        self._ef['0th'][piexif.ImageIFD.Model] = model

    def add_dop(self, dop, precision=100):
        """Add GPSDOP (float)."""
        self._ef["GPS"][piexif.GPSIFD.GPSDOP] = (
            int(abs(dop) * precision), precision)

    def add_altitude(self, altitude, precision=100):
        """Add altitude (pre is the precision)."""
        ref = 0 if altitude > 0 else 1
        self._ef["GPS"][piexif.GPSIFD.GPSAltitude] = (
            int(abs(altitude) * precision), precision)
        self._ef["GPS"][piexif.GPSIFD.GPSAltitudeRef] = ref

    def add_direction(self, direction, ref="T", precision=100):
        """Add image direction."""
        # normalize direction
        direction = direction % 360.0
        self._ef["GPS"][piexif.GPSIFD.GPSImgDirection] = (
            int(abs(direction) * precision), precision)
        self._ef["GPS"][piexif.GPSIFD.GPSImgDirectionRef] = ref

    def add_firmware(self,firmware_string):
        """Add firmware version of camera"""
        self._ef['0th'][piexif.ImageIFD.Software] = firmware_string

    def add_custom_tag(self, value, main_key, tag_key):
        try:
            self._ef[main_key][tag_key] = value
        except:
            print("could not set tag {} under {} with value {}".format(
                tag_key, main_key, value))

    def write(self, filename=None):
        """Save exif data to file."""
        if filename is None:
            filename = self._filename

        exif_bytes = piexif.dump(self._ef)

        with open(self._filename, "rb") as fin:
            img = fin.read()
        try:
            piexif.insert(exif_bytes, img, filename)

        except IOError:
            type, value, traceback = sys.exc_info()
            print >> sys.stderr, "Error saving file:", value