# Authors: see git history
#
# Copyright (c) 2010 Authors
# Licensed under the GNU GPL version 3.0 or later.  See the file LICENSE for details.

import json
import os
import socket
import sys
import time
import webbrowser
from contextlib import closing
from copy import deepcopy
from datetime import date
from threading import Thread

import wx
from flask import Flask, Response, jsonify, request, send_from_directory
from jinja2 import Environment, FileSystemLoader, select_autoescape
from lxml import etree
from werkzeug.serving import make_server

from ..debug.debug import debug
from ..i18n import _, get_languages
from ..i18n import translation as inkstitch_translation
from ..stitch_plan import stitch_groups_to_stitch_plan
from ..svg import render_stitch_plan
from ..threads import ThreadCatalog
from ..utils import get_resource_dir, get_user_dir
from .base import InkstitchExtension


def datetimeformat(value, format='%Y/%m/%d'):
    return value.strftime(format)


def defaults_path():
    return get_user_dir('print_settings.json')


def load_defaults():
    try:
        with open(defaults_path(), 'r') as defaults_file:
            defaults = json.load(defaults_file)
            return defaults
    except BaseException:
        return {}


def save_defaults(defaults):
    with open(defaults_path(), 'w') as defaults_file:
        json.dump(defaults, defaults_file)


def open_url(url):
    # Avoid spurious output from xdg-open.  Any output on stdout will crash
    # inkscape.
    null = open(os.devnull, 'w')
    old_stdout = os.dup(sys.stdout.fileno())
    os.dup2(null.fileno(), sys.stdout.fileno())

    if getattr(sys, 'frozen', False):

        # PyInstaller sets LD_LIBRARY_PATH.  We need to temporarily clear it
        # to avoid confusing xdg-open, which webbrowser will run.

        # The following code is adapted from PyInstaller's documentation
        # http://pyinstaller.readthedocs.io/en/stable/runtime-information.html

        old_environ = dict(os.environ)  # make a copy of the environment
        lp_key = 'LD_LIBRARY_PATH'  # for Linux and *BSD.
        lp_orig = os.environ.get(lp_key + '_ORIG')  # pyinstaller >= 20160820 has this
        if lp_orig is not None:
            os.environ[lp_key] = lp_orig  # restore the original, unmodified value
        else:
            os.environ.pop(lp_key, None)  # last resort: remove the env var

        webbrowser.open(url)

        # restore the old environ
        os.environ.clear()
        os.environ.update(old_environ)
    else:
        webbrowser.open(url)

    # restore file descriptors
    os.dup2(old_stdout, sys.stdout.fileno())
    os.close(old_stdout)


class PrintPreviewServer(Thread):
    def __init__(self, *args, **kwargs):
        self.html = kwargs.pop('html')
        self.metadata = kwargs.pop('metadata')
        self.stitch_plan = kwargs.pop('stitch_plan')
        self.realistic_overview_svg = kwargs.pop('realistic_overview_svg')
        self.realistic_color_block_svgs = kwargs.pop('realistic_color_block_svgs')
        Thread.__init__(self, *args, **kwargs)
        self.daemon = True
        self.last_request_time = None
        self.shutting_down = False
        self.flask_server = None
        self.server_thread = None
        self.started = False

        self.__setup_app()

    def __set_resources_path(self):
        self.resources_path = os.path.join(get_resource_dir('print'), 'resources')

    def __setup_app(self):  # noqa: C901
        self.__set_resources_path()

        # Disable warning about using a development server in a production environment
        cli = sys.modules['flask.cli']
        cli.show_server_banner = lambda *x: None

        self.app = Flask(__name__)

        self.watcher_thread = Thread(target=self.watch)
        self.watcher_thread.daemon = True
        self.watcher_thread.start()

        @self.app.before_request
        def request_started():
            self.last_request_time = time.time()

        @self.app.route('/')
        def index():
            return self.html

        @self.app.route('/shutdown', methods=['POST'])
        def shutdown():
            self.shutting_down = True
            return _('Closing...') + '<br/><br/>' + _('It is safe to close this window now.')

        @self.app.route('/resources/<path:resource>', methods=['GET'])
        def resources(resource):
            return send_from_directory(self.resources_path, resource, max_age=1)

        @self.app.route('/ping')
        def ping():
            debug.log("got a ping")
            # Javascript is letting us know it's still there.  This resets self.last_request_time.
            return "pong"

        @self.app.route('/settings/<field_name>', methods=['POST'])
        def set_field(field_name):
            self.metadata[field_name] = request.json['value']
            return "OK"

        @self.app.route('/settings/<field_mame>', methods=['GET'])
        def get_field(field_name):
            return jsonify(self.metadata[field_name])

        @self.app.route('/settings', methods=['GET'])
        def get_settings():
            settings = {}
            settings.update(load_defaults())
            settings.update(self.metadata)
            return jsonify(settings)

        @self.app.route('/defaults', methods=['POST'])
        def set_defaults():
            save_defaults(request.json['value'])
            return "OK"

        @self.app.route('/palette', methods=['POST'])
        def set_palette():
            name = request.json['name']
            catalog = ThreadCatalog()
            palette = catalog.get_palette_by_name(name)
            catalog.apply_palette(self.stitch_plan, palette)

            # clear any saved color or thread names
            for field in self.metadata:
                if field.startswith('color-') or field.startswith('thread-'):
                    del self.metadata[field]

            self.metadata['thread-palette'] = name

            return "OK"

        @self.app.route('/threads', methods=['GET'])
        def get_threads():
            threads = []
            for color_block in self.stitch_plan:
                threads.append({
                    'hex': color_block.color.hex_digits,
                    'name': color_block.color.name,
                    'manufacturer': color_block.color.manufacturer,
                    'number': color_block.color.number,
                })

            return jsonify(threads)

        @self.app.route('/realistic/block<int:index>', methods=['GET'])
        def get_realistic_block(index):
            return Response(self.realistic_color_block_svgs[index], mimetype='image/svg+xml')

        @self.app.route('/realistic/overview', methods=['GET'])
        def get_realistic_overview():
            return Response(self.realistic_overview_svg, mimetype='image/svg+xml')

        @self.app.route('/printing/start')
        def printing_start():
            # temporarily turn off the watcher while the print dialog is up,
            # because javascript will be frozen
            self.last_request_time = None
            return "OK"

        @self.app.route('/printing/end')
        def printing_end():
            # nothing to do here -- request_started() will restart the watcher
            return "OK"

    def stop(self):
        self.flask_server.shutdown()
        self.server_thread.join()

    def watch(self):
        try:
            while True:
                time.sleep(1)
                if self.shutting_down:
                    debug.log("watcher thread: shutting down")
                    self.stop()
                    break

                if self.last_request_time is not None and (time.time() - self.last_request_time) > 3:
                    debug.log("watcher thread: timed out, stopping")
                    self.stop()
                    break
        except BaseException:
            # seems like sometimes this thread blows up during shutdown
            debug.log(f"exception in watcher {sys.exc_info()}")
            pass

    # https://github.com/aluo-x/Learning_Neural_Acoustic_Fields/blob/master/train.py
    # https://github.com/pytorch/pytorch/issues/71029
    def find_free_port(self):
        with closing(socket.socket(socket.AF_INET, socket.SOCK_STREAM)) as s:
            s.bind(('localhost', 0))
            return s.getsockname()[1]

    def run(self):
        self.host = "127.0.0.1"
        self.port = self.find_free_port()
        # exporting the port number for languages to work
        os.environ['FLASKPORT'] = str(self.port)

        self.flask_server = make_server(self.host, self.port, self.app)
        self.server_thread = Thread(target=self.flask_server.serve_forever)
        self.server_thread.start()
        self.started = True
        self.server_thread.join()


class PrintInfoFrame(wx.Frame):
    def __init__(self, *args, **kwargs):
        self.print_server = kwargs.pop("print_server")
        wx.Frame.__init__(self, *args, **kwargs)

        panel = wx.Panel(self)
        sizer = wx.BoxSizer(wx.VERTICAL)

        self.message = _(
            "A print preview has been opened in your web browser.  "
            "This window will stay open in order to communicate with the JavaScript code running in your browser.\n\n"
            "This window will close after you close the print preview in your browser, or you can close it manually if necessary."
        )
        self.text = wx.StaticText(panel, label=self.message)
        font = wx.Font(14, wx.DEFAULT, wx.NORMAL, wx.NORMAL)
        self.text.SetFont(font)
        self.Bind(wx.EVT_SIZE, self.resize)
        sizer.Add(self.text, proportion=1, flag=wx.ALL | wx.EXPAND, border=20)

        stop_button = wx.Button(panel, id=wx.ID_CLOSE)
        stop_button.Bind(wx.EVT_BUTTON, self.close_button_clicked)
        sizer.Add(stop_button, proportion=0, flag=wx.ALIGN_CENTER | wx.ALL, border=10)

        panel.SetSizer(sizer)
        panel.Layout()

        self.timer = wx.PyTimer(self.__watcher)
        self.timer.Start(250)

    def resize(self, event=None):
        self.text.SetLabel(self.message)
        self.text.Wrap(self.GetSize().width - 35)
        self.Layout()

    def close_button_clicked(self, event):
        self.print_server.stop()

    def __watcher(self):
        if self.print_server.started and not self.print_server.is_alive():
            self.timer.Stop()
            self.timer = None
            self.Destroy()


class Print(InkstitchExtension):
    def build_environment(self):
        print_dir = get_resource_dir('print')
        template_dir = os.path.join(print_dir, "templates")

        env = Environment(
            loader=FileSystemLoader(template_dir),
            autoescape=select_autoescape(['html', 'xml']),
            extensions=['jinja2.ext.i18n']
        )

        env.filters['datetimeformat'] = datetimeformat
        env.install_gettext_translations(inkstitch_translation)

        languages_with_style = []
        languages = get_languages()
        for lang in languages:
            css_file = "%s.css" % lang
            if os.path.isfile(os.path.join(print_dir, "resources", css_file)):
                languages_with_style.append(lang)
        env.languages = languages_with_style

        return env

    def strip_namespaces(self, svg):
        # namespace prefixes seem to trip up HTML, so get rid of them
        for element in svg.iter():
            if isinstance(element.tag, str) and element.tag[0] == '{':
                element.tag = element.tag[element.tag.index('}', 1) + 1:]

    def render_svgs(self, stitch_plan, realistic=False):
        svg = deepcopy(self.document).getroot()
        render_stitch_plan(svg, stitch_plan, realistic, visual_commands=False)

        self.strip_namespaces(svg)

        # Now the stitch plan layer will contain a set of groups, each
        # corresponding to a color block.  We'll create a set of SVG files
        # corresponding to each individual color block and a final one
        # for all color blocks together.

        layers_and_groups = svg.xpath("./g|./path|./circle|./ellipse|./rect|./text")
        stitch_plan_layer = svg.findone(".//*[@id='__inkstitch_stitch_plan__']")

        # Make sure there is no leftover translation from stitch plan preview
        stitch_plan_layer.pop('transform')

        # objects outside of the viewbox are invisible
        # TODO: if we want them to be seen, we need to redefine document size to fit the design
        #       this is just a quick fix and doesn't work on realistic view
        svg.set('style', 'overflow:visible;')

        # First, delete all of the other layers.  We don't need them and they'll
        # just bulk up the SVG.
        for layer in layers_and_groups:
            if layer is not stitch_plan_layer:
                layer.delete()

        overview_svg = etree.tostring(svg).decode('utf-8')
        color_block_groups = stitch_plan_layer.getchildren()
        color_block_svgs = []

        for i, group in enumerate(color_block_groups):
            # clear the stitch plan layer
            del stitch_plan_layer[:]

            # add in just this group
            stitch_plan_layer.append(group)

            # save an SVG preview
            color_block_svgs.append(etree.tostring(svg).decode('utf-8'))

        return overview_svg, color_block_svgs

    def render_html(self, stitch_plan, overview_svg, selected_palette):
        env = self.build_environment()
        template = env.get_template('index.html')

        return template.render(
            view={
                'client_overview': False,
                'client_detailedview': False,
                'operator_overview': True,
                'operator_detailedview': True,
                'full_page_patternview': False,
                'show_footer': False,
                'custom_page': False
            },
            logo={'src': '', 'title': 'LOGO'},
            date=date.today(),
            client="",
            job={
                'title': '',
                'num_colors': stitch_plan.num_colors,
                'num_color_blocks': len(stitch_plan),
                'num_stops': stitch_plan.num_stops,
                'num_trims': stitch_plan.num_trims,
                'dimensions': stitch_plan.dimensions_mm,
                'num_stitches': stitch_plan.num_stitches,
                'estimated_thread': stitch_plan.estimated_thread
            },
            svg_overview=overview_svg,
            color_blocks=stitch_plan.color_blocks,
            palettes=ThreadCatalog().palette_names(),
            selected_palette=selected_palette,
            languages=env.languages
        )

    def effect(self):
        # It doesn't really make sense to print just a couple of selected
        # objects.  It's almost certain they meant to print the whole design.
        # If they really wanted to print just a few objects, they could set
        # the rest invisible temporarily.
        self.svg.selection.clear()

        if not self.get_elements():
            return

        self.metadata = self.get_inkstitch_metadata()
        collapse_len = self.metadata['collapse_len_mm']
        min_stitch_len = self.metadata['min_stitch_len_mm']
        stitch_groups = self.elements_to_stitch_groups(self.elements)
        stitch_plan = stitch_groups_to_stitch_plan(stitch_groups, collapse_len=collapse_len, min_stitch_len=min_stitch_len)
        palette = ThreadCatalog().match_and_apply_palette(stitch_plan, self.get_inkstitch_metadata()['thread-palette'])

        overview_svg, color_block_svgs = self.render_svgs(stitch_plan, realistic=False)
        realistic_overview_svg, realistic_color_block_svgs = self.render_svgs(stitch_plan, realistic=True)

        for i, svg in enumerate(color_block_svgs):
            stitch_plan.color_blocks[i].svg_preview = svg

        html = self.render_html(stitch_plan, overview_svg, palette)

        print_server = PrintPreviewServer(
            html=html,
            metadata=self.get_inkstitch_metadata(),
            stitch_plan=stitch_plan,
            realistic_overview_svg=realistic_overview_svg,
            realistic_color_block_svgs=realistic_color_block_svgs
        )
        print_server.start()

        time.sleep(1)
        open_url("http://%s:%s/" % (print_server.host, print_server.port))

        app = wx.App()
        info_frame = PrintInfoFrame(None, title=_("Ink/Stitch Print"), size=(450, 350), print_server=print_server)
        info_frame.Show()
        app.MainLoop()