#!/usr/bin/env python

# =================================================================
#
# Authors: Adam Hinz <hinz.adam@gmail.com>
#
# Copyright (c) 2015 Adam Hinz
#
# Permission is hereby granted, free of charge, to any person
# obtaining a copy of this software and associated documentation
# files (the "Software"), to deal in the Software without
# restriction, including without limitation the rights to use,
# copy, modify, merge, publish, distribute, sublicense, and/or sell
# copies of the Software, and to permit persons to whom the
# Software is furnished to do so, subject to the following
# conditions:
#
# The above copyright notice and this permission notice shall be
# included in all copies or substantial portions of the Software.
#
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
# EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
# OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
# NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
# HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
# WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
# FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
# OTHER DEALINGS IN THE SOFTWARE.
#
# =================================================================

# WSGI wrapper for pycsw
#
# Apache mod_wsgi configuration
#
# ServerName host1
# WSGIDaemonProcess host1 home=/var/www/pycsw processes=2
# WSGIProcessGroup host1
#
# WSGIScriptAlias /pycsw-wsgi /var/www/pycsw/csw.wsgi
#
# <Directory /var/www/pycsw>
# Order deny,allow
#  Allow from all
# </Directory>
#
# or invoke this script from the command line:
#
# $ python ./csw.wsgi
#
# which will publish pycsw to:
#
# http://localhost:8000/
#

#%module
#% description: CSW wsgi handler
#% keyword: csw
#% keyword: metadata
#%end

#%option
#% key: path
#% description: path to pycsw instal folder
#% required : yes
#% answer : /var/www/html/pycsw
#%end

#%option
#% key: port
#% type: integer
#% description: server port
#% required : yes
#% answer: 8000
#%end

from io import StringIO
import os
import sys
import contextlib

from grass.script import core as grass
from grass.script.utils import set_path

set_path(modulename="wx.metadata", dirname="mdlib", path="..")

from mdlib import globalvar

app_path = None


@contextlib.contextmanager
def application(env, start_response):
    """WSGI wrapper"""
    config = "default.cfg"

    if "PYCSW_CONFIG" in env:
        config = env["PYCSW_CONFIG"]

    if env["QUERY_STRING"].lower().find("config") != -1:
        for kvp in env["QUERY_STRING"].split("&"):
            if kvp.lower().find("config") != -1:
                config = kvp.split("=")[1]

    if not os.path.isabs(config):
        config = os.path.join(app_path, config)

    if "HTTP_HOST" in env and ":" in env["HTTP_HOST"]:
        env["HTTP_HOST"] = env["HTTP_HOST"].split(":")[0]

    env["local.app_root"] = app_path

    csw = server.Csw(config, env)

    gzip = False
    if "HTTP_ACCEPT_ENCODING" in env and env["HTTP_ACCEPT_ENCODING"].find("gzip") != -1:
        # set for gzip compressed response
        gzip = True

    # set compression level
    if csw.config.has_option("server", "gzip_compresslevel"):
        gzip_compresslevel = int(csw.config.get("server", "gzip_compresslevel"))
    else:
        gzip_compresslevel = 0

    status, contents = csw.dispatch_wsgi()

    headers = {}

    if gzip and gzip_compresslevel > 0:
        import gzip

        buf = StringIO()
        gzipfile = gzip.GzipFile(
            mode="wb", fileobj=buf, compresslevel=gzip_compresslevel
        )
        gzipfile.write(contents)
        gzipfile.close()

        contents = buf.getvalue()

        headers["Content-Encoding"] = "gzip"

    headers["Content-Length"] = str(len(contents))
    headers["Content-Type"] = csw.contenttype

    start_response(status, list(headers.items()))

    return [contents]


def main():
    try:
        global server
        from pycsw import server
    except ModuleNotFoundError as e:
        msg = e.msg
        grass.fatal(
            globalvar.MODULE_NOT_FOUND.format(
                lib=msg.split("'")[-2], url=globalvar.MODULE_URL
            )
        )

    path = options["path"]
    port = int(options["port"])
    path = os.path.dirname(path)

    app_path = os.path.dirname(path)
    sys.path.append(app_path)

    from wsgiref.simple_server import make_server

    try:
        httpd = make_server("", port, application)
        grass.message("Serving on port %d..." % port)
    except Exception as e:
        grass.error(str(e))
        sys.stdout.flush()
        sys.exit()

    httpd.serve_forever()
    sys.stdout.flush()


if __name__ == "__main__":
    options, flags = grass.parser()
    main()