package scraper

import (
	"time"
	"fmt"

	"offline_twitter/terminal_utils"
)

const DEFAULT_MAX_REPLIES_EAGER_LOAD = 50

type TweetID int64

type Tweet struct {
	ID             TweetID
	UserID         UserID
	User           *User
	Text           string
	PostedAt       time.Time
	NumLikes       int
	NumRetweets    int
	NumReplies     int
	NumQuoteTweets int
	InReplyTo      TweetID

	Urls        []Url
	Images      []Image
	Videos      []Video
	Mentions    []UserHandle
	Hashtags    []string
	QuotedTweet TweetID

	IsContentDownloaded bool
}


func (t Tweet) String() string {
	var author string
	if t.User != nil {
		author = fmt.Sprintf("%s\n@%s", t.User.DisplayName, t.User.Handle)
	} else {
		author = "@???"
	}

	ret := fmt.Sprintf(
`%s
%s
%s
Replies: %d      RT: %d      QT: %d      Likes: %d
`,
		author,
		terminal_utils.FormatDate(t.PostedAt),
		terminal_utils.WrapText(t.Text, 60),
		t.NumReplies,
		t.NumRetweets,
		t.NumQuoteTweets,
		t.NumLikes,
	)

	if len(t.Images) > 0 {
		ret += fmt.Sprintf(terminal_utils.COLOR_GREEN + "images: %d\n" + terminal_utils.COLOR_RESET, len(t.Images))
	}
	if len(t.Urls) > 0 {
		ret += "urls: [\n"
		for _, url := range(t.Urls) {
			ret += "  " + url.Text + "\n"
		}
		ret += "]"
	}

	return ret
}

// Turn an APITweet, as returned from the scraper, into a properly structured Tweet object
func ParseSingleTweet(apiTweet APITweet) (ret Tweet, err error) {
	apiTweet.NormalizeContent()

	ret.ID = TweetID(apiTweet.ID)
	ret.UserID = UserID(apiTweet.UserID)
	ret.Text = apiTweet.FullText

	ret.PostedAt, err = time.Parse(time.RubyDate, apiTweet.CreatedAt)
	if err != nil {
		return
	}
	ret.NumLikes = apiTweet.FavoriteCount
	ret.NumRetweets = apiTweet.RetweetCount
	ret.NumReplies = apiTweet.ReplyCount
	ret.NumQuoteTweets = apiTweet.QuoteCount
	ret.InReplyTo = TweetID(apiTweet.InReplyToStatusID)

	for _, url := range apiTweet.Entities.URLs {
		var url_object Url
		if apiTweet.Card.ShortenedUrl == url.ShortenedUrl {
			url_object = ParseAPIUrlCard(apiTweet.Card)
		}
		url_object.Text = url.ExpandedURL
		url_object.TweetID = ret.ID
		ret.Urls = append(ret.Urls, url_object)
	}

	for _, media := range apiTweet.Entities.Media {
		if media.Type != "photo" {  // TODO: remove this eventually
			panic_str := fmt.Sprintf("Unknown media type: %q", media.Type)
			panic(panic_str)
		}
		new_image := ParseAPIMedia(media)
		new_image.TweetID = ret.ID
		ret.Images = append(ret.Images, new_image)
	}
	for _, hashtag := range apiTweet.Entities.Hashtags {
		ret.Hashtags = append(ret.Hashtags, hashtag.Text)
	}
	for _, mention := range apiTweet.Entities.Mentions {
		ret.Mentions = append(ret.Mentions, UserHandle(mention.UserName))
	}

	ret.QuotedTweet = TweetID(apiTweet.QuotedStatusID)

	for _, entity := range apiTweet.ExtendedEntities.Media {
		if entity.Type != "video" {
			continue
		}
		if len(apiTweet.ExtendedEntities.Media) != 1 {
			panic(fmt.Sprintf("Surprising ExtendedEntities: %v", apiTweet.ExtendedEntities.Media))
		}
		new_video := ParseAPIVideo(apiTweet.ExtendedEntities.Media[0], ret.ID)
		ret.Videos = []Video{new_video}
		ret.Images = []Image{}
	}
	return
}


/**
 * Get a single tweet with no replies from the API.
 *
 * args:
 * - id: the ID of the tweet to get
 *
 * returns: the single Tweet
 */
func GetTweet(id TweetID) (Tweet, error) {
	api := API{}
	tweet_response, err := api.GetTweet(id, "")
	if err != nil {
		return Tweet{}, fmt.Errorf("Error in API call: %s", err)
	}

	single_tweet, ok := tweet_response.GlobalObjects.Tweets[fmt.Sprint(id)]

	if !ok {
		return Tweet{}, fmt.Errorf("Didn't get the tweet!\n%v", tweet_response)
	}

	return ParseSingleTweet(single_tweet)
}


/**
 * Return a list of tweets, including the original and the rest of its thread,
 * along with a list of associated users.
 *
 * args:
 * - id: the ID of the tweet to get
 *
 * returns: the tweet, list of its replies and context, and users associated with those replies
 */
func GetTweetFull(id TweetID) (tweets []Tweet, retweets []Retweet, users []User, err error) {
	api := API{}
	tweet_response, err := api.GetTweet(id, "")
	if err != nil {
		return
	}
	if len(tweet_response.GlobalObjects.Tweets) < DEFAULT_MAX_REPLIES_EAGER_LOAD &&
			tweet_response.GetCursor() != "" {
		err = api.GetMoreReplies(id, &tweet_response, DEFAULT_MAX_REPLIES_EAGER_LOAD)
		if err != nil {
			return
		}
	}

	return ParseTweetResponse(tweet_response)
}

/**
 * Parse an API response object into a list of tweets, retweets and users
 *
 * args:
 * - resp: the response from the API
 *
 * returns: a list of tweets, retweets and users in that response object
 */
func ParseTweetResponse(resp TweetResponse) (tweets []Tweet, retweets []Retweet, users []User, err error) {
	var new_tweet Tweet
	var new_retweet Retweet
	for _, single_tweet := range resp.GlobalObjects.Tweets {
		if single_tweet.RetweetedStatusIDStr == "" {
			new_tweet, err = ParseSingleTweet(single_tweet)
			if err != nil {
				return
			}
			tweets = append(tweets, new_tweet)
		} else {
			new_retweet, err = ParseSingleRetweet(single_tweet)
			if err != nil {
				return
			}
			retweets = append(retweets, new_retweet)
		}
	}
	var new_user User
	for _, user := range resp.GlobalObjects.Users {
		new_user, err = ParseSingleUser(user)
		if err != nil {
			return
		}
		users = append(users, new_user)
	}
	return
}