# -*- coding: utf-8 -*-
##

from gi.repository import GObject, Gtk, GLib
import os
import sys
import time
from urllib.request import Request, urlopen
import mimetypes        # better use the magic packet, but that's not a standard lib
import gtkgui_helpers
import logging
from queue import Queue
import binascii

from common import gajim
from common import ged
import chat_control
from plugins import GajimPlugin
from plugins.helpers import log_calls
from dialogs import FileChooserDialog, ImageChooserDialog, ErrorDialog
import nbxmpp

from .thumbnail import thumbnail

log = logging.getLogger('gajim.plugin_system.httpupload')

if os.name != 'nt':
    try:
        from cryptography.hazmat.backends import default_backend
        from cryptography.hazmat.primitives.ciphers import Cipher
        from cryptography.hazmat.primitives.ciphers import algorithms
        from cryptography.hazmat.primitives.ciphers.modes import GCM
        encryption_available = True
    except Exception as e:
        log.debug(e)
        encryption_available = False
else:
    encryption_available = False
    log.info('Cryptography not available on Windows for now')

# XEP-0363 (http://xmpp.org/extensions/xep-0363.html)
NS_HTTPUPLOAD = 'urn:xmpp:http:upload'
TAGSIZE = 16

jid_to_servers = {}
iq_ids_to_callbacks = {}
last_info_query = {}


class HttpuploadPlugin(GajimPlugin):

    @log_calls('HttpuploadPlugin')
    def init(self):
        self.config_dialog = None  # HttpuploadPluginConfigDialog(self)
        self.controls = []
        self.events_handlers = {}
        self.events_handlers['agent-info-received'] = (ged.PRECORE,
                self.handle_agent_info_received)
        self.events_handlers['raw-iq-received'] = (ged.PRECORE,
                self.handle_iq_received)
        self.gui_extension_points = {
            'chat_control_base': (self.connect_with_chat_control,
                self.disconnect_from_chat_control),
            'chat_control_base_update_toolbar': (self.update_button_state,
                None)}
        self.first_run = True

    def handle_iq_received(self, event):
        global iq_ids_to_callbacks
        id_ = event.stanza.getAttr("id")
        if str(id_) in iq_ids_to_callbacks:
            try:
                iq_ids_to_callbacks[str(id_)](event.stanza)
            except:
                raise
            finally:
                del iq_ids_to_callbacks[str(id_)]

    def handle_agent_info_received(self, event):
        global jid_to_servers
        if NS_HTTPUPLOAD in event.features and gajim.jid_is_transport(event.jid):
            own_jid = gajim.get_jid_without_resource(str(event.stanza.getTo()))
            jid_to_servers[own_jid] = event.jid        # map own jid to upload component's jid
            log.info(own_jid + " can do http uploads via component " + event.jid)
            # update all buttons
            for base in self.controls:
                self.update_button_state(base.chat_control)

    @log_calls('HttpuploadPlugin')
    def connect_with_chat_control(self, control):
        self.chat_control = control
        base = Base(self, self.chat_control)
        self.controls.append(base)
        if self.first_run:
            # TODO: Potentially add back keyboard shortcut
            self.first_run = False
        self.update_button_state(self.chat_control)

    @log_calls('HttpuploadPlugin')
    def disconnect_from_chat_control(self, chat_control):
        for control in self.controls:
            control.disconnect_from_chat_control()
        self.controls = []

    @log_calls('HttpuploadPlugin')
    def update_button_state(self, chat_control):
        global jid_to_servers
        global iq_ids_to_callbacks
        global last_info_query

        if gajim.connections[chat_control.account].connection == None and \
            gajim.get_jid_from_account(chat_control.account) in jid_to_servers:
            # maybe don't delete this and detect vanished upload components when actually trying to upload something
            log.info("Deleting %s from jid_to_servers (disconnected)" % gajim.get_jid_from_account(chat_control.account))
            del jid_to_servers[gajim.get_jid_from_account(chat_control.account)]
            #pass

        # query info at most every 60 seconds in case something goes wrong
        if ((not chat_control.account in last_info_query or
             last_info_query[chat_control.account] + 60 < time.time())
            and not gajim.get_jid_from_account(chat_control.account) in jid_to_servers
            and gajim.account_is_connected(chat_control.account)
        ):
            log.info("Account %s: Using dicovery to find jid of httpupload component" % chat_control.account)
            id_ = gajim.get_an_id()
            iq = nbxmpp.Iq(
                typ='get',
                to=gajim.get_server_from_jid(gajim.get_jid_from_account(chat_control.account)),
                queryNS="http://jabber.org/protocol/disco#items"
            )
            iq.setID(id_)
            def query_info(stanza):
                global last_info_query
                for item in stanza.getTag("query").getTags("item"):
                    id_ = gajim.get_an_id()
                    iq = nbxmpp.Iq(
                        typ='get',
                        to=item.getAttr("jid"),
                        queryNS="http://jabber.org/protocol/disco#info"
                    )
                    iq.setID(id_)
                    last_info_query[chat_control.account] = time.time()
                    gajim.connections[chat_control.account].connection.send(iq)
            iq_ids_to_callbacks[str(id_)] = query_info
            gajim.connections[chat_control.account].connection.send(iq)
            #send disco query to main server jid
            id_ = gajim.get_an_id()
            iq = nbxmpp.Iq(
                typ='get',
                to=gajim.get_server_from_jid(gajim.get_jid_from_account(chat_control.account)),
                queryNS="http://jabber.org/protocol/disco#info"
            )
            iq.setID(id_)
            last_info_query[chat_control.account] = time.time()
            gajim.connections[chat_control.account].connection.send(iq)

        for base in self.controls:
            if base.chat_control == chat_control:
                is_supported = gajim.get_jid_from_account(chat_control.account) in jid_to_servers and \
                    gajim.connections[chat_control.account].connection != None
                log.info("Account %s: httpupload is_supported: %s" % (str(chat_control.account), str(is_supported)))
                if not is_supported:
                    text = _('Your server does not support http uploads')
                    image_text = text
                else:
                    text = _('Send file via http upload')
                    image_text = _('Send image via http upload')
                base.button.set_sensitive(is_supported)
                base.button.set_tooltip_text(text)
                base.image_button.set_sensitive(is_supported)
                base.image_button.set_tooltip_text(image_text)


class Base(object):
    def __init__(self, plugin, chat_control):
        self.dlg = None
        self.dialog_type = 'file'
        self.plugin = plugin
        self.encrypted_upload = False
        self.chat_control = chat_control
        actions_hbox = chat_control.xml.get_object('actions_hbox')
        self.button = Gtk.Button(label=None, stock=None, use_underline=True)
        self.button.set_property('can-focus', False)
        self.button.set_sensitive(False)
        img = Gtk.Image()
        img.set_from_file(self.plugin.local_file_path('httpupload.png'))
        self.button.set_image(img)
        self.button.set_tooltip_text(_('Your server does not support http uploads'))
        self.button.set_relief(Gtk.ReliefStyle.NONE)
        self.image_button = Gtk.Button(label=None, stock=None, use_underline=True)
        self.image_button.set_property('can-focus', False)
        self.image_button.set_relief(Gtk.ReliefStyle.NONE)
        self.image_button.set_sensitive(False)
        img = Gtk.Image()
        img.set_from_file(self.plugin.local_file_path('image.png'))
        self.image_button.set_image(img)
        self.image_button.set_tooltip_text(_('Your server does not support http uploads'))
        send_button = chat_control.xml.get_object('send_button')
        actions_hbox.add(self.button)
        actions_hbox.add(self.image_button)

        send_button_pos = actions_hbox.child_get_property(send_button, 'position')
        actions_hbox.child_set_property(self.image_button, 'position', send_button_pos - 1)
        actions_hbox.child_set_property(self.button, 'position', send_button_pos - 1)

        file_id = self.button.connect('clicked', self.on_file_button_clicked)
        image_id = self.image_button.connect('clicked', self.on_image_button_clicked)
        chat_control.handlers[file_id] = self.button
        chat_control.handlers[image_id] = self.image_button
        self.button.show()
        self.image_button.show()


    def disconnect_from_chat_control(self):
        actions_hbox = self.chat_control.xml.get_object('actions_hbox')
        actions_hbox.remove(self.button)
        actions_hbox.remove(self.image_button)

    def encryption_activated(self):
        if not encryption_available:
            return False
        jid = self.chat_control.contact.jid
        account = self.chat_control.account
        for plugin in gajim.plugin_manager.active_plugins:
            if type(plugin).__name__ == 'OmemoPlugin':
                omemo = plugin
                break
        if omemo:
            state = omemo.get_omemo_state(account)
            log.info('Encryption is: ' +
                      str(state.encryption.is_active(jid)))
            return state.encryption.is_active(jid)
        log.info('Encryption is: False / OMEMO not found')
        return False

    def on_file_dialog_ok(self, widget, path_to_file=None):
        global jid_to_servers

        try:
            self.encrypted_upload = self.encryption_activated()
        except Exception as e:
            log.debug(e)
            self.encrypted_upload = False

        if not path_to_file:
            path_to_file = self.dlg.get_filename()
            if not path_to_file:
                self.dlg.destroy()
                return
        self.dlg.destroy()
        if not os.path.exists(path_to_file):
            return
        if self.encrypted_upload:
            filesize = os.path.getsize(path_to_file) + TAGSIZE  # in bytes
        else:
            filesize = os.path.getsize(path_to_file)
        invalid_file = False
        msg = ''
        if os.path.isfile(path_to_file):
            stat = os.stat(path_to_file)
            if stat[6] == 0:
                invalid_file = True
                msg = _('File is empty')
        else:
            invalid_file = True
            msg = _('File does not exist')
        if invalid_file:
            ErrorDialog(_('Could not open file'), msg, transient_for=self.chat_control.parent_win.window)
            return

        mime_type = mimetypes.MimeTypes().guess_type(path_to_file)[0]
        if not mime_type:
            mime_type = 'application/octet-stream'  # fallback mime type
        log.info("Detected MIME Type of file: " + str(mime_type))
        progress_messages = Queue(8)
        progress_window = ProgressWindow(_('HTTP Upload'), _('Requesting HTTP Upload Slot...'), progress_messages, self.plugin)
        def upload_file(stanza):
            slot = stanza.getTag("slot")
            if not slot:
                log.error("got unexpected stanza: "+str(stanza))
                progress_window.close_dialog()
                error = stanza.getTag("error")
                if error and error.getTag("text"):
                    ErrorDialog(_('Could not request upload slot'),
                                _('Got unexpected response from server: %s') % str(error.getTagData("text")),
                                transient_for=self.chat_control.parent_win.window)
                else:
                    ErrorDialog(_('Could not request upload slot'),
                                _('Got unexpected response from server (protocol mismatch??)'),
                                transient_for=self.chat_control.parent_win.window)
                return

            try:
                if self.encrypted_upload:
                    key = os.urandom(32)
                    iv = os.urandom(16)
                    data = StreamFileWithProgress(path_to_file,
                                                  "rb",
                                                  progress_window.update_progress,
                                                  self.encrypted_upload, key, iv)
                else:
                    data = StreamFileWithProgress(path_to_file,
                                                  "rb",
                                                  progress_window.update_progress)
            except:
                log.error("Could not open file")
                progress_window.close_dialog()
                ErrorDialog(_('Could not open file'),
                            _('Exception raised while opening file (see error log for more information)'),
                            transient_for=self.chat_control.parent_win.window)
                raise       # fill error log with useful information

            put = slot.getTag("put")
            get = slot.getTag("get")
            if not put or not get:
                log.error("got unexpected stanza: " + str(stanza))
                progress_window.close_dialog()
                ErrorDialog(_('Could not request upload slot'),
                            _('Got unexpected response from server (protocol mismatch??)'),
                            transient_for=self.chat_control.parent_win.window)
                return

            def upload_complete(response_code):
                if response_code == 0:
                    return      # Upload was aborted
                if 200 <= response_code < 300:
                    log.info("Upload completed successfully")
                    xhtml = None
                    is_image = mime_type.split('/', 1)[0] == 'image'
                    if ((not isinstance(self.chat_control, chat_control.ChatControl)
                         or not self.chat_control.gpg_is_active)
                        and self.dialog_type == 'image'
                        and is_image
                        and not self.encrypted_upload
                    ):
                        progress_messages.put(_('Calculating (possible) image thumbnail...'))
                        thumb = thumbnail(path_to_file)
                        if thumb:
                            xhtml = '<body><br/><a href="%s"><img alt="%s" src="data:image/jpeg;base64,%s"/></a></body>' % \
                                (get.getData(), get.getData(), thumb)
                    progress_window.close_dialog()
                    id_ = gajim.get_an_id()
                    def add_oob_tag():
                        pass
                    if self.encrypted_upload:
                        keyAndIv = '#' + binascii.hexlify(iv) + binascii.hexlify(key)
                        self.chat_control.send_message(message=get.getData() + keyAndIv, xhtml=None)
                    else:
                        self.chat_control.send_message(message=get.getData(), xhtml=xhtml)
                    self.chat_control.msg_textview.grab_focus()
                else:
                    progress_window.close_dialog()
                    log.error("got unexpected http upload response code: " + str(response_code))
                    ErrorDialog(_('Could not upload file'),
                                _('Got unexpected http response code from server: ') + str(response_code),
                                transient_for=self.chat_control.parent_win.window)

            def on_upload_error():
                progress_window.close_dialog()
                ErrorDialog(_('Could not upload file'),
                            _('Got unexpected exception while uploading file'
                              ' (see error log for more information)'),
                            transient_for=self.chat_control.parent_win.window)
                return 0

            def uploader():
                progress_messages.put(_('Uploading file via HTTP...'))
                try:
                    headers = {'User-Agent': 'Gajim %s' % gajim.version,
                               'Content-Type': mime_type}
                    request = Request(put.getData(), data=data, headers=headers, method='PUT')
                    log.debug("opening urllib upload request...")
                    transfer = urlopen(request, timeout=30)
                    data.close()
                    log.debug("urllib upload request done, response code: " + str(transfer.getcode()))
                    return transfer.getcode()
                except UploadAbortedException:
                    log.info("Upload aborted")
                except:
                    log.error("Exception during upload", exc_info=sys.exc_info())
                    GLib.idle_add(on_upload_error)
                return 0

            log.info("Uploading file to '%s'..." % str(put.getData()))
            log.info("Please download from '%s' later..." % str(get.getData()))

            gajim.thread_interface(uploader, [], upload_complete)

        is_supported = gajim.get_jid_from_account(self.chat_control.account) in jid_to_servers and \
                    gajim.connections[self.chat_control.account].connection != None
        log.info("jid_to_servers of %s: %s ; connection: %s",
                 gajim.get_jid_from_account(self.chat_control.account),
                 str(jid_to_servers[gajim.get_jid_from_account(self.chat_control.account)]),
                 str(gajim.connections[self.chat_control.account].connection))
        if not is_supported:
            progress_window.close_dialog()
            log.error("upload component vanished, account got disconnected??")
            ErrorDialog(_('Your server does not support http uploads or you just got disconnected.\nPlease try to reconnect or reopen the chat window to fix this.'),
                transient_for=self.chat_control.parent_win.window)
            return

        # create iq for slot request
        id_ = gajim.get_an_id()
        iq = nbxmpp.Iq(
            typ='get',
            to=jid_to_servers[gajim.get_jid_from_account(self.chat_control.account)],
            queryNS=None
        )
        iq.setID(id_)
        request = iq.addChild(
            name="request",
            namespace=NS_HTTPUPLOAD
        )
        filename = request.addChild(
            name="filename",
        )
        filename.addData(os.path.basename(path_to_file))
        size = request.addChild(
            name="size",
        )
        size.addData(filesize)
        content_type = request.addChild(
            name="content-type",
        )
        content_type.addData(mime_type)

        # send slot request and register callback
        log.debug("sending httpupload slot request iq...")
        iq_ids_to_callbacks[str(id_)] = upload_file
        gajim.connections[self.chat_control.account].connection.send(iq)

        self.chat_control.msg_textview.grab_focus()

    def on_file_button_clicked(self, widget):
        self.dialog_type = 'file'
        self.dlg = FileChooserDialog(on_response_ok=self.on_file_dialog_ok, on_response_cancel=None,
            title_text = _('Choose file to send'), action = Gtk.FileChooserAction.OPEN,
            buttons = (Gtk.STOCK_CANCEL, Gtk.ResponseType.CANCEL, Gtk.STOCK_OPEN, Gtk.ResponseType.OK),
            default_response = Gtk.ResponseType.OK,)

    def on_image_button_clicked(self, widget):
        self.dialog_type = 'image'
        self.dlg = ImageChooserDialog(on_response_ok=self.on_file_dialog_ok, on_response_cancel=None)


class StreamFileWithProgress:
    def __init__(self, path, mode, callback=None,
                 encrypted_upload=False, key=None, iv=None, *args):
        self.backing = open(path, mode)
        self.encrypted_upload = encrypted_upload
        self.backing.seek(0, os.SEEK_END)
        if self.encrypted_upload:
            self.encryptor = Cipher(
                algorithms.AES(key),
                GCM(iv),
                backend=default_backend()).encryptor()
            self._total = self.backing.tell() + TAGSIZE
        else:
            self._total = self.backing.tell()
        self.backing.seek(0)
        self._callback = callback
        self._args = args
        self._seen = 0

    def __len__(self):
        return self._total

    def read(self, size):
        if self.encrypted_upload:
            data = self.backing.read(size)
            if len(data) > 0:
                data = self.encryptor.update(data)
                self._seen += len(data)
                if (self._seen + TAGSIZE) == self._total:
                    self.encryptor.finalize()
                    data += self.encryptor.tag
                    self._seen += TAGSIZE
                if self._callback:
                    self._callback(self._seen, self._total, *self._args)
            return data
        else:
            data = self.backing.read(size)
            self._seen += len(data)
            if self._callback:
                self._callback(self._seen, self._total, *self._args)
            return data

    def close(self):
        return self.backing.close()


class ProgressWindow:
    def __init__(self, title_text, during_text, messages_queue, plugin):
        self.plugin = plugin
        self.xml = gtkgui_helpers.get_gtk_builder(self.plugin.local_file_path('upload_progress_dialog.ui'))
        self.messages_queue = messages_queue
        self.dialog = self.xml.get_object('progress_dialog')
        self.label = self.xml.get_object('label')
        self.cancel_button = self.xml.get_object('close_button')
        self.label.set_markup('<big>' + during_text + '</big>')
        self.progressbar = self.xml.get_object('progressbar')
        self.progressbar.set_text("")
        self.dialog.set_title(title_text)
        #self.dialog.set_geometry_hints(min_width=400, min_height=96)
        #self.dialog.set_position(Gtk.WIN_POS_CENTER_ON_PARENT)
        self.dialog.show_all()
        self.xml.connect_signals(self)

        self.stopped = False
        self.pulse_progressbar_timeout_id = GObject.timeout_add(100, self.pulse_progressbar)
        self.process_messages_queue_timeout_id = GObject.timeout_add(100, self.process_messages_queue)


    def pulse_progressbar(self):
        if self.dialog:
            self.progressbar.pulse()
            return True # loop forever
        return False

    def process_messages_queue(self):
        if not self.messages_queue.empty():
            self.label.set_markup('<big>' + self.messages_queue.get() + '</big>')
        if self.dialog:
            return True # loop forever
        return False

    def on_progress_dialog_delete_event(self, widget, event):
        self.stopped = True
        if self.pulse_progressbar_timeout_id:
            GObject.source_remove(self.pulse_progressbar_timeout_id)
        GObject.source_remove(self.process_messages_queue_timeout_id)

    def on_cancel(self, widget):
        self.stopped = True
        if self.pulse_progressbar_timeout_id:
            GObject.source_remove(self.pulse_progressbar_timeout_id)
        GObject.source_remove(self.process_messages_queue_timeout_id)
        self.dialog.destroy()

    def update_progress(self, seen, total):
        if self.stopped == True:
            raise UploadAbortedException
        if self.pulse_progressbar_timeout_id:
            GObject.source_remove(self.pulse_progressbar_timeout_id)
            self.pulse_progressbar_timeout_id = None
        pct = (float(seen) / total) * 100.0
        self.progressbar.set_fraction(float(seen) / total)
        self.progressbar.set_text(str(int(pct)) + "%")
        log.debug('upload progress: %.2f%% (%d of %d bytes)' % (pct, seen, total))

    def close_dialog(self):
        self.on_cancel(None)

class UploadAbortedException(Exception):
    def __str__(self):
        return "Upload Aborted"