package main

import (
	"context"

	"github.com/mmcdole/gofeed"
)

var _ Source = &RssFeed{}

type RssFeed struct {
	name     string
	url      string
	content  string
	language Language
	feed     *gofeed.Feed
}

func (r *RssFeed) Name() string {
	return r.name
}

func (r *RssFeed) Language() Language {
	return r.language
}

func (r *RssFeed) getFeed(ctx context.Context) error {
	fp := gofeed.NewParser()
	feed, err := fp.ParseURLWithContext(r.url, ctx)
	if err != nil {
		return err
	}
	r.feed = feed
	return nil
}

func (r RssFeed) Len(ctx context.Context) (int, error) {
	if r.feed == nil {
		if err := r.getFeed(ctx); err != nil {
			return -1, err
		}
	}
	return r.feed.Len(), nil
}

func (r *RssFeed) Get(ctx context.Context, i int) (*Article, error) {
	if r.feed == nil {
		if err := r.getFeed(ctx); err != nil {
			return nil, err
		}
	}
	item := r.feed.Items[i]
	textOnly := extractText(item.Content)
	return &Article{raw: textOnly}, nil
}