{-# LANGUAGE OverloadedStrings #-}

module Main where

import Data.Aeson
import Data.ByteString.Char8 ()
import qualified Data.Map as M
import Data.Maybe
import Data.Text
import qualified Data.Vector as V

import Web.Hyperpublic
import qualified Web.Hyperpublic.Places as Places
import qualified Web.Hyperpublic.Offers as Offers


-- Sequence the two examples.
main :: IO ()
main = placeNamesNearHq >> offerDescr


-- Find places near Hyperpublic HQ and print the name of each.
placeNamesNearHq :: IO ()
placeNamesNearHq =
    let json = Places.find auth [( "address"
                                 , "416 W 13th St, New York, NY 10014" )]
    in json >>= putStrLn . show . getNames
  where
    getNames (Array arr) = mapMaybe getName $ V.toList arr
    getName (Object obj) = getTextField obj "display_name"

-- Find the offer with id 4e90567c297a200001008db9 and print its description.
offerDescr :: IO ()
offerDescr =
    let json = Offers.show auth "4e90567c297a200001008db9"
    in json >>= putStrLn . show . getDescr
  where
    getDescr (Object obj) = maybe "" id $ getTextField obj "description"


-- Create an authorization record. Get your own credentials at
-- http://www.hyperpublic.com/registerapi
auth :: HpAuth
auth = HpAuth { clientId = "8UufhI6bCKQXKMBn7AUWO67Yq6C8RkfD0BGouTke"
              , clientSecret = "zdoROY5XRN0clIWsEJyKzHedSK4irYee8jpnOXaP" }

-- Extract a text field from an 'Data.Aeson.Object'.
getTextField :: Object -> Text -> Maybe Text
getTextField obj txt = M.lookup txt obj >>= resultToMaybe . fromJSON
  where
    resultToMaybe (Success a) = Just a
    resultToMaybe (Error _) = Nothing