"""A simple number and datetime addition JSON API.
Run the app:

    $ python examples/bottle_example.py

Try the following with httpie (a cURL-like utility, http://httpie.org):

    $ pip install httpie
    $ http GET :5001/
    $ http GET :5001/ name==Ada
    $ http POST :5001/add x=40 y=2
    $ http POST :5001/dateadd value=1973-04-10 addend=63
    $ http POST :5001/dateadd value=2014-10-23 addend=525600 unit=minutes
"""
import datetime as dt

from bottle import route, run, error, response
from webargs import fields, validate
from webargs.bottleparser import use_args, use_kwargs


hello_args = {"name": fields.Str(missing="Friend")}


@route("/", method="GET", apply=use_args(hello_args))
def index(args):
    """A welcome page."""
    return {"message": "Welcome, {}!".format(args["name"])}


add_args = {"x": fields.Float(required=True), "y": fields.Float(required=True)}


@route("/add", method="POST", apply=use_kwargs(add_args))
def add(x, y):
    """An addition endpoint."""
    return {"result": x + y}


dateadd_args = {
    "value": fields.Date(required=False),
    "addend": fields.Int(required=True, validate=validate.Range(min=1)),
    "unit": fields.Str(missing="days", validate=validate.OneOf(["minutes", "days"])),
}


@route("/dateadd", method="POST", apply=use_kwargs(dateadd_args))
def dateadd(value, addend, unit):
    """A date adder endpoint."""
    value = value or dt.datetime.utcnow()
    if unit == "minutes":
        delta = dt.timedelta(minutes=addend)
    else:
        delta = dt.timedelta(days=addend)
    result = value + delta
    return {"result": result.isoformat()}


# Return validation errors as JSON
@error(400)
@error(422)
def handle_error(err):
    response.content_type = "application/json"
    return err.body


if __name__ == "__main__":
    run(port=5001, reloader=True, debug=True)