# Copyright 2018 AT&T Intellectual Property.  All other rights reserved.
#
# Licensed under the Apache License, Version 2.0 (the 'License');
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an 'AS IS' BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.


import json
import logging
import os
import sys

import click
import yaml

from flask import Flask, request, render_template, send_from_directory
from flask_bootstrap import Bootstrap


app_path = os.path.dirname(os.path.abspath(__file__))
app = Flask(
    "Yaml Editor!",
    template_folder=os.path.join(app_path, "templates"),
    static_folder=os.path.join(app_path, "static"),
)
Bootstrap(app)
logging.getLogger("werkzeug").setLevel(logging.ERROR)
LOG = app.logger


@app.route("/favicon.ico")
def favicon():
    return send_from_directory(app.static_folder, "favicon.ico")


@app.route("/", methods=["GET", "POST"])
def index():
    """Renders index page to edit provided yaml file."""
    LOG.info("Rendering yaml file for editing")
    with open(app.config["YAML_FILE"]) as file_obj:
        data = yaml.safe_load(file_obj)
    return render_template(
        "yaml.html",
        data=json.dumps(data),
        change_str=app.config["STRING_TO_CHANGE"],
    )


@app.route("/save", methods=["POST"])
def save():
    """Save current progress on file."""
    LOG.info("Saving edited inputs from user to yaml file")
    out = request.json.get("yaml_data")
    with open(app.config["YAML_FILE"], "w") as file_obj:
        yaml.safe_dump(out, file_obj, default_flow_style=False)
    return "Data saved successfully!"


@app.route("/saveExit", methods=["POST"])
def save_exit():
    """Save current progress on file and shuts down the server."""
    LOG.info(
        "Saving edited inputs from user to yaml file and shutting"
        " down server"
    )
    out = request.json.get("yaml_data")
    with open(app.config["YAML_FILE"], "w") as file_obj:
        yaml.safe_dump(out, file_obj, default_flow_style=False)
    func = request.environ.get("werkzeug.server.shutdown")
    if func:
        func()
    return "Saved successfully, Shutting down app! You may close the tab!"


@app.errorhandler(404)
def page_not_found(e):
    """Serves 404 error."""
    LOG.info("User tried to access unavailable page.")
    return "<h1>404: Page not Found!</h1>"


def run(*args, **kwargs):
    """Starts the server."""
    LOG.info("Initiating web server for yaml editing")
    port = kwargs.get("port", None)
    if not port:
        port = 8161
    app.run(host="0.0.0.0", port=port, debug=False)


@click.command()
@click.option(
    "--file",
    "-f",
    required=True,
    type=click.File(),
    multiple=False,
    help="Path with file name to the intermediary yaml file.",
)
@click.option(
    "--host",
    "-h",
    default="0.0.0.0",
    type=click.STRING,
    multiple=False,
    help="Optional host parameter to run Flask on.",
)
@click.option(
    "--port",
    "-p",
    default=8161,
    type=click.INT,
    multiple=False,
    help="Optional port parameter to run Flask on.",
)
@click.option(
    "--string",
    "-s",
    default="#CHANGE_ME",
    type=click.STRING,
    multiple=False,
    help="Text which is required to be changed on yaml file.",
)
def main(*args, **kwargs):
    LOG.setLevel(logging.INFO)
    LOG.info("Initiating yaml-editor")
    try:
        yaml.safe_load(kwargs["file"])
    except yaml.YAMLError as e:
        LOG.error("EXITTING - Please provide a valid yaml file.")
        if hasattr(e, "problem_mark"):
            mark = e.problem_mark
            LOG.error(
                "Error position: ({0}:{1})".format(
                    mark.line + 1, mark.column + 1
                )
            )
        sys.exit(2)
    except Exception:
        LOG.error("EXITTING - Please provide a valid yaml file.")
        sys.exit(2)
    LOG.info(
        """

##############################################################################

Please go to http://{0}:{1}/ to edit your yaml file.

##############################################################################

    """.format(
            kwargs["host"], kwargs["port"]
        )
    )
    app.config["YAML_FILE"] = kwargs["file"].name
    app.config["STRING_TO_CHANGE"] = kwargs["string"]
    run(*args, **kwargs)


if __name__ == "__main__":
    """Invoked when used as a script."""
    main()