package main

import (
	"github.com/gorilla/mux"
	"log"
	"net/http"
	"encoding/json"
	"fmt"
)

type Trend [] struct {
	Trends [] struct {
		Name            string `json:"name,omitempty"`
		Url             string `json:"url,omitempty"`
		PromotedContent string `promoted_content:"lastname,omitempty"`
		Query           string `json:"query,omitempty"`
		TweetVolume     int    `json:"tweet_volume,omitempty"`
	} `json:"trends"`
}

func main() {

	router := mux.NewRouter()
	router.HandleFunc("/hashtags", GetHashtags).Methods("GET")
	router.HandleFunc("/hashtags/{woeid}", GetHashtagFromWOEID).Methods("GET")
	log.Fatal(http.ListenAndServe(":8000", router))
}

func GetHashtags(w http.ResponseWriter, r *http.Request) {

	body := sendRequestToTwitter("1")
	jsonResponse, err := json.Marshal(body)
	if err != nil {
		panic(err)
	}

	w.Write(jsonResponse)
}

func GetHashtagFromWOEID(w http.ResponseWriter, r *http.Request) {

	params := mux.Vars(r)
	body := sendRequestToTwitter(params["woeid"])
	jsonResponse, err := json.Marshal(body)
	if err != nil {
		panic(err)
	}

	w.Write(jsonResponse)
}

func sendRequestToTwitter(WOEID string) []string {

	url := "https://api.twitter.com/1.1/trends/place.json?id=" + WOEID
	req, _ := http.NewRequest("GET", url, nil)
	req.Header.Add("Authorization", "Bearer AAAAAAAAAAAAAAAAAAAAAKCtPAAAAAAAq1L5CTf40mf5K%2B7Q6QcWxsyjNvo%3DRkSK8AQBdk6latG2h47XWJVSQdn98heLv8HDLDhviicP3xvodm")
	req.Header.Add("Cache-Control", "no-cache")
	req.Header.Add("Accept", "application/json")
	res, _ := http.DefaultClient.Do(req)

	defer res.Body.Close()
	trends := Trend{}
	var hashtags []string

	err := json.NewDecoder(res.Body).Decode(&trends)
	if err != nil {
		fmt.Printf("Error while parsing data: %s", err)
	}

	for _, t := range trends[0].Trends {
		hashtags = append(hashtags, t.Name)
		println(t.Name)
	}

	return hashtags
}