# -*- coding: utf-8 -*-
"""
OnionShare | https://onionshare.org/

Copyright (C) 2014-2020 Micah Lee, et al. <micah@micahflee.com>

This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with this program.  If not, see <http://www.gnu.org/licenses/>.
"""

import os
import sys
import tempfile
import zipfile
import mimetypes
from flask import Response, request, render_template, make_response

from .send_base_mode import SendBaseModeWeb
from .. import strings


class ShareModeWeb(SendBaseModeWeb):
    """
    All of the web logic for share mode
    """

    def init(self):
        self.common.log("ShareModeWeb", "init")

        # Allow downloading individual files if "Stop sharing after files have been sent" is unchecked
        self.download_individual_files = not self.web.settings.get(
            "share", "autostop_sharing"
        )

    def define_routes(self):
        """
        The web app routes for sharing files
        """

        @self.web.app.route("/", defaults={"path": ""})
        @self.web.app.route("/<path:path>")
        def index(path):
            """
            Render the template for the onionshare landing page.
            """
            self.web.add_request(self.web.REQUEST_LOAD, request.path)

            # Deny new downloads if "Stop sharing after files have been sent" is checked and there is
            # currently a download
            deny_download = (
                self.web.settings.get("share", "autostop_sharing")
                and self.download_in_progress
            )
            if deny_download:
                r = make_response(
                    render_template("denied.html"),
                    static_url_path=self.web.static_url_path,
                )
                return self.web.add_security_headers(r)

            # If download is allowed to continue, serve download page
            if self.should_use_gzip():
                self.filesize = self.gzip_filesize
            else:
                self.filesize = self.download_filesize

            return self.render_logic(path)

        @self.web.app.route("/download")
        def download():
            """
            Download the zip file.
            """
            # Deny new downloads if "Stop After First Download" is checked and there is
            # currently a download
            deny_download = (
                self.web.settings.get("share", "autostop_sharing")
                and self.download_in_progress
            )
            if deny_download:
                r = make_response(
                    render_template(
                        "denied.html", static_url_path=self.web.static_url_path
                    )
                )
                return self.web.add_security_headers(r)

            # Prepare some variables to use inside generate() function below
            # which is outside of the request context
            shutdown_func = request.environ.get("werkzeug.server.shutdown")
            path = request.path

            # If this is a zipped file, then serve as-is. If it's not zipped, then,
            # if the http client supports gzip compression, gzip the file first
            # and serve that
            use_gzip = self.should_use_gzip()
            if use_gzip:
                file_to_download = self.gzip_filename
                self.filesize = self.gzip_filesize
            else:
                file_to_download = self.download_filename
                self.filesize = self.download_filesize

            # Tell GUI the download started
            history_id = self.cur_history_id
            self.cur_history_id += 1
            self.web.add_request(
                self.web.REQUEST_STARTED, path, {"id": history_id, "use_gzip": use_gzip}
            )

            basename = os.path.basename(self.download_filename)

            def generate():
                # Starting a new download
                if self.web.settings.get("share", "autostop_sharing"):
                    self.download_in_progress = True

                chunk_size = 102400  # 100kb

                fp = open(file_to_download, "rb")
                self.web.done = False
                canceled = False
                while not self.web.done:
                    # The user has canceled the download, so stop serving the file
                    if not self.web.stop_q.empty():
                        self.web.add_request(
                            self.web.REQUEST_CANCELED, path, {"id": history_id}
                        )
                        break

                    chunk = fp.read(chunk_size)
                    if chunk == b"":
                        self.web.done = True
                    else:
                        try:
                            yield chunk

                            # tell GUI the progress
                            downloaded_bytes = fp.tell()
                            percent = (1.0 * downloaded_bytes / self.filesize) * 100

                            # only output to stdout if running onionshare in CLI mode, or if using Linux (#203, #304)
                            if (
                                not self.web.is_gui
                                or self.common.platform == "Linux"
                                or self.common.platform == "BSD"
                            ):
                                sys.stdout.write(
                                    "\r{0:s}, {1:.2f}%          ".format(
                                        self.common.human_readable_filesize(
                                            downloaded_bytes
                                        ),
                                        percent,
                                    )
                                )
                                sys.stdout.flush()

                            self.web.add_request(
                                self.web.REQUEST_PROGRESS,
                                path,
                                {"id": history_id, "bytes": downloaded_bytes},
                            )
                            self.web.done = False
                        except:
                            # looks like the download was canceled
                            self.web.done = True
                            canceled = True

                            # tell the GUI the download has canceled
                            self.web.add_request(
                                self.web.REQUEST_CANCELED, path, {"id": history_id}
                            )

                fp.close()

                if self.common.platform != "Darwin":
                    sys.stdout.write("\n")

                # Download is finished
                if self.web.settings.get("share", "autostop_sharing"):
                    self.download_in_progress = False

                # Close the server, if necessary
                if self.web.settings.get("share", "autostop_sharing") and not canceled:
                    print("Stopped because transfer is complete")
                    self.web.running = False
                    try:
                        if shutdown_func is None:
                            raise RuntimeError("Not running with the Werkzeug Server")
                        shutdown_func()
                    except:
                        pass

            r = Response(generate())
            if use_gzip:
                r.headers.set("Content-Encoding", "gzip")
            r.headers.set("Content-Length", self.filesize)
            r.headers.set("Content-Disposition", "attachment", filename=basename)
            r = self.web.add_security_headers(r)
            # guess content type
            (content_type, _) = mimetypes.guess_type(basename, strict=False)
            if content_type is not None:
                r.headers.set("Content-Type", content_type)
            return r

    def directory_listing_template(
        self, path, files, dirs, breadcrumbs, breadcrumbs_leaf
    ):
        return make_response(
            render_template(
                "send.html",
                file_info=self.file_info,
                files=files,
                dirs=dirs,
                breadcrumbs=breadcrumbs,
                breadcrumbs_leaf=breadcrumbs_leaf,
                filename=os.path.basename(self.download_filename),
                filesize=self.filesize,
                filesize_human=self.common.human_readable_filesize(
                    self.download_filesize
                ),
                is_zipped=self.is_zipped,
                static_url_path=self.web.static_url_path,
                download_individual_files=self.download_individual_files,
            )
        )

    def set_file_info_custom(self, filenames, processed_size_callback):
        self.common.log("ShareModeWeb", "set_file_info_custom")
        self.web.cancel_compression = False
        self.build_zipfile_list(filenames, processed_size_callback)

    def render_logic(self, path=""):
        if path in self.files:
            filesystem_path = self.files[path]

            # If it's a directory
            if os.path.isdir(filesystem_path):
                # Render directory listing
                filenames = []
                for filename in os.listdir(filesystem_path):
                    if os.path.isdir(os.path.join(filesystem_path, filename)):
                        filenames.append(filename + "/")
                    else:
                        filenames.append(filename)
                filenames.sort()
                return self.directory_listing(filenames, path, filesystem_path)

            # If it's a file
            elif os.path.isfile(filesystem_path):
                if self.download_individual_files:
                    return self.stream_individual_file(filesystem_path)
                else:
                    history_id = self.cur_history_id
                    self.cur_history_id += 1
                    return self.web.error404(history_id)

            # If it's not a directory or file, throw a 404
            else:
                history_id = self.cur_history_id
                self.cur_history_id += 1
                return self.web.error404(history_id)
        else:
            # Special case loading /

            if path == "":
                # Root directory listing
                filenames = list(self.root_files)
                filenames.sort()
                return self.directory_listing(filenames, path)

            else:
                # If the path isn't found, throw a 404
                history_id = self.cur_history_id
                self.cur_history_id += 1
                return self.web.error404(history_id)

    def build_zipfile_list(self, filenames, processed_size_callback=None):
        self.common.log("ShareModeWeb", "build_zipfile_list")
        for filename in filenames:
            info = {
                "filename": filename,
                "basename": os.path.basename(filename.rstrip("/")),
            }
            if os.path.isfile(filename):
                info["size"] = os.path.getsize(filename)
                info["size_human"] = self.common.human_readable_filesize(info["size"])
                self.file_info["files"].append(info)
            if os.path.isdir(filename):
                info["size"] = self.common.dir_size(filename)
                info["size_human"] = self.common.human_readable_filesize(info["size"])
                self.file_info["dirs"].append(info)
        self.file_info["files"] = sorted(
            self.file_info["files"], key=lambda k: k["basename"]
        )
        self.file_info["dirs"] = sorted(
            self.file_info["dirs"], key=lambda k: k["basename"]
        )

        # Check if there's only 1 file and no folders
        if len(self.file_info["files"]) == 1 and len(self.file_info["dirs"]) == 0:
            self.download_filename = self.file_info["files"][0]["filename"]
            self.download_filesize = self.file_info["files"][0]["size"]

            # Compress the file with gzip now, so we don't have to do it on each request
            self.gzip_filename = tempfile.mkstemp("wb+")[1]
            self._gzip_compress(
                self.download_filename, self.gzip_filename, 6, processed_size_callback
            )
            self.gzip_filesize = os.path.getsize(self.gzip_filename)

            # Make sure the gzip file gets cleaned up when onionshare stops
            self.cleanup_filenames.append(self.gzip_filename)

            self.is_zipped = False

        else:
            # Zip up the files and folders
            self.zip_writer = ZipWriter(
                self.common, processed_size_callback=processed_size_callback
            )
            self.download_filename = self.zip_writer.zip_filename
            for info in self.file_info["files"]:
                self.zip_writer.add_file(info["filename"])
                # Canceling early?
                if self.web.cancel_compression:
                    self.zip_writer.close()
                    return False

            for info in self.file_info["dirs"]:
                if not self.zip_writer.add_dir(info["filename"]):
                    return False

            self.zip_writer.close()
            self.download_filesize = os.path.getsize(self.download_filename)

            # Make sure the zip file gets cleaned up when onionshare stops
            self.cleanup_filenames.append(self.zip_writer.zip_filename)

            self.is_zipped = True

        return True


class ZipWriter(object):
    """
    ZipWriter accepts files and directories and compresses them into a zip file
    with. If a zip_filename is not passed in, it will use the default onionshare
    filename.
    """

    def __init__(self, common, zip_filename=None, processed_size_callback=None):
        self.common = common
        self.cancel_compression = False

        if zip_filename:
            self.zip_filename = zip_filename
        else:
            self.zip_filename = (
                f"{tempfile.mkdtemp()}/onionshare_{self.common.random_string(4, 6)}.zip"
            )

        self.z = zipfile.ZipFile(self.zip_filename, "w", allowZip64=True)
        self.processed_size_callback = processed_size_callback
        if self.processed_size_callback is None:
            self.processed_size_callback = lambda _: None
        self._size = 0
        self.processed_size_callback(self._size)

    def add_file(self, filename):
        """
        Add a file to the zip archive.
        """
        self.z.write(filename, os.path.basename(filename), zipfile.ZIP_DEFLATED)
        self._size += os.path.getsize(filename)
        self.processed_size_callback(self._size)

    def add_dir(self, filename):
        """
        Add a directory, and all of its children, to the zip archive.
        """
        dir_to_strip = os.path.dirname(filename.rstrip("/")) + "/"
        for dirpath, dirnames, filenames in os.walk(filename):
            for f in filenames:
                # Canceling early?
                if self.cancel_compression:
                    return False

                full_filename = os.path.join(dirpath, f)
                if not os.path.islink(full_filename):
                    arc_filename = full_filename[len(dir_to_strip) :]
                    self.z.write(full_filename, arc_filename, zipfile.ZIP_DEFLATED)
                    self._size += os.path.getsize(full_filename)
                    self.processed_size_callback(self._size)

        return True

    def close(self):
        """
        Close the zip archive.
        """
        self.z.close()
