package main

import (
	"log"
	"encoding/json"
	"net/http"
	"time"
)

type VideoDetails struct {
	Author       string     `json:"author"`
	Channel      string     `json:"channel"`
	Published    time.Time  `json:"published"`
	Description  string     `json:"description"`
	Comments     int        `json:"comments"`     // nunber of comments
	Likes        int        `json:"likes"`
	Views        int        `json:"views"`
	Tags         []string   `json:"tags"`
}

type Comment struct {
	Author     string      `json:"author"`
	Body       string      `json:"body"`
	Published  time.Time   `json:"published"`
	Updated    time.Time   `json:"updated,omitempty"`
	Likes      int         `json:"likes"`
	Replies    []*Comment  `json:"replies,omitempty"`
}

type APISource interface {
	getDetails(id string)   (VideoDetails, error)
	getComments(id string)  ([]Comment, error)
}

func apiDataHandler[T any](f func(id string) (T, error)) http.HandlerFunc {
	return func(w http.ResponseWriter, r *http.Request) {
		videoID := r.URL.Query().Get("id")
		if videoID == "" {
			msg := "Missing ?id=VIDEO_ID parameter"
			http.Error(w, msg, http.StatusBadRequest)
			return
		}

		data, err := f(videoID)
		if err != nil {
			http.Error(w, err.Error(), http.StatusInternalServerError)
			log.Println(err.Error())
			return
		}

		w.Header().Set("Content-Type", "application/json")
		json.NewEncoder(w).Encode(data)
	}
}

func registerRoutesAPI(mux *http.ServeMux, api APISource) {
	mux.HandleFunc("/api/details", apiDataHandler(api.getDetails))
	mux.HandleFunc("/api/comments", apiDataHandler(api.getComments))
}