package main

import (
	"bufio"
	"errors"
	"html"
	"net/url"
	"strings"
	"time"

	"github.com/PuerkitoBio/goquery"
	"github.com/jbowtie/gokogiri"
	gokogirixml "github.com/jbowtie/gokogiri/xml"
	"github.com/lunny/html2md"
	"github.com/microcosm-cc/bluemonday"
	"mvdan.cc/xurls/v2"
)

//FBPostData FBPostData
type FBPostData struct {
	PostURL     string
	TimeStamp   string
	ProfileLink *ProfileLink
	GiftURL     string
	ImageURL    string
	Content     string
	Summary     string
	Title       string
	Author      string
	Tags        string
}

// ParsePost ParsePost
func ParsePost(s, PostURL string) (*FBPostData, error) {
	fb := FBPostData{PostURL: PostURL}

	docKogiri, err := gokogiri.ParseHtml([]byte(s))
	if err != nil {
		return &fb, err
	}
	defer docKogiri.Free()
	htmlNode := docKogiri.Root().FirstChild()

	//doc, err := goquery.NewDocumentFromReader(strings.NewReader(s))
	//if err != nil {
	//	return &fb, err
	//}

	fb.TimeStamp, err = GetTimeStamp(htmlNode)
	if err != nil {
		return &fb, err
	}

	//fmt.Printf("\n\n%#v\n\n", dataFT)

	//fb.ProfileLink, err = GetProfileLink(doc)
	//if err != nil {
	//	return &fb, err
	//}

	fb.ImageURL, err = GetImageURL(htmlNode)
	if err != nil {
		return &fb, err
	}

	fb.GiftURL, err = GetGiftURL(htmlNode)
	if err != nil {
		return &fb, err
	}

	fb.PostURL, err = GetPostURL(htmlNode)
	if err != nil {
		fb.PostURL = PostURL
		return &fb, err
	}

	fb.Content, err = GetContent(htmlNode)
	if err != nil {
		return &fb, err
	}

	if strings.Contains(fb.Content, SearchFreeSilverCaskets) {
		if len(fb.Title) == 0 {
			fb.Title = TitleFreeSilverCaskets
		} else {
			fb.Title = TitleFreeSilverCaskets + "+" + fb.Title
		}
	}

	if strings.Contains(fb.Content, SearchFreeTitanArtifact) {
		if len(fb.Title) == 0 {
			fb.Title = TitleFreeTitanArtifact
		} else {
			fb.Title = TitleFreeTitanArtifact + "+" + fb.Title
		}
	}

	if strings.Contains(fb.Content, SearchFreeSoulStones) {
		if len(fb.Title) == 0 {
			fb.Title = TitleFreeSoulStones
		} else {
			fb.Title = TitleFreeSoulStones + "+" + fb.Title
		}
	}

	if strings.Contains(fb.Content, SearchFreeSkinStones) {
		if len(fb.Title) == 0 {
			fb.Title = TitleFreeSkinStones
		} else {
			fb.Title = TitleFreeSkinStones + "+" + fb.Title
		}
	}

	if strings.Contains(fb.Content, SearchActionKeepTheAmount) {
		if len(fb.Title) == 0 {
			fb.Title = TitleActionKeepTheAmount
		} else {
			fb.Title = TitleActionKeepTheAmount + "+" + fb.Title
		}
		fb.GiftURL = fb.PostURL
	}

	if strings.Contains(fb.Content, SearchFreeWinterfestBaubles) {
		if len(fb.Title) == 0 {
			fb.Title = TitleFreeWinterfestBaubles
		} else {
			fb.Title = TitleFreeWinterfestBaubles + "+" + fb.Title
		}
	}

	if strings.Contains(fb.Content, SearchFreeTopFanPackage) {
		if len(fb.Title) == 0 {
			fb.Title = TitleFreeTopFanPackage
		} else {
			fb.Title = TitleFreeTopFanPackage + "+" + fb.Title
		}
	}

	if strings.Contains(fb.Content, SearchFreeEnergyForFee) {
		if len(fb.Title) == 0 {
			fb.Title = TitleFreeEnergyForFee
		} else {
			fb.Title = TitleFreeEnergyForFee + "+" + fb.Title
		}
	}

	if strings.Contains(fb.Content, SearchWinterfestRankingRewards) {
		if len(fb.Title) == 0 {
			fb.Title = TitleWinterfestRankingRewards
		} else {
			fb.Title = TitleWinterfestRankingRewards + "+" + fb.Title
		}
	}

	if len(fb.Title) == 0 {
		fb.Title = "unknown - need to implemented"
	}
	defer func() {
		dataFT = nil
	}()

	return &fb, nil
}

// Parse Parse
func Parse(url string) (*FBPostData, error) {
	doc, err := goquery.NewDocument(url)
	if err != nil {
		return nil, err
	}

	if strings.Contains(url, ".blogspot.") {
		return ParseBlogspotPost(doc)
	}

	// If not login, post looks like
	// <div class="hidden_elem"><code id="u_0_p"><!-- ... --></code></div>
	s := QuerySelector(doc, "div.hidden_elem > code")
	cmt, err := s.Html()
	if err != nil {
		return nil, err
	}
	if len(cmt) != 0 {
		return ParsePost(cmt, url)
	}

	s = QuerySelector(doc, "div._427x")
	cmt, err = s.Html()
	if err != nil {
		return nil, err
	}
	return ParsePost(cmt, url)
}

// ParseAll ParseAll
func ParseAll(url string) ([]*FBPostData, error) {
	doc, err := goquery.NewDocument(url)
	if err != nil {
		return nil, err
	}

	allFbPosts := []*FBPostData{}

	QuerySelectorEach(doc, "div._427x", func(i int, selected *goquery.Selection) {
		cmt, err := selected.Html()
		if err != nil {
			return
		}
		fbPost, err := ParsePost(cmt, url)
		if err != nil {
			return
		}
		allFbPosts = append(allFbPosts, fbPost)
	})

	return allFbPosts, nil
}

// GetContent GetContent
func GetContent(htmlNode gokogirixml.Node) (string, error) {
	results, err := htmlNode.Search(xPathArticleContent)
	if err != nil {
		//fmt.Printf("ERR: %#v -- %#v\n", results, err)
		return "", err
	}
	//fmt.Printf("ERR: %#v -- %#v\n", results, err)
	if len(results) > 0 {
		if resultHTML := results[0].InnerHtml(); resultHTML != "" {

			bmsanizer := bluemonday.StrictPolicy()
			bmsanizer.AllowAttrs("href").OnElements("a")
			bmsanizer.AllowElements("p")
			bmsanizer.RequireParseableURLs(true)
			htmlText := bmsanizer.SanitizeBytes([]byte(resultHTML))

			content := strings.Join(strings.Fields(string(htmlText)), " ")
			content = html2md.Convert(content)
			content = html.UnescapeString(content)
			content = strings.TrimSpace(content)

			return content, nil
		}
	}
	return "", errors.New("no content found")
}

// GetImageURL GetImageURL
func GetImageURL(htmlNode gokogirixml.Node) (string, error) {

	results, err := htmlNode.Search(xPathImageURL)
	if err != nil {
		//fmt.Printf("ERR: %#v -- %#v\n", results, err)
		return "", err
	}
	//fmt.Printf("RESULT: %#v -- %#v\n", results, err)
	// search for the second possible image
	if len(results) == 0 {
		results, err = htmlNode.Search(xPathImageURL2)
		if err != nil {
			//fmt.Printf("ERR2: %#v -- %#v\n", results, err)
			return "", err
		}
	}
	// Video Preview
	if len(results) == 0 {
		results, err = htmlNode.Search(xPathImageURL3)
		if err != nil {
			//fmt.Printf("ERR2: %#v -- %#v\n", results, err)
			return "", err
		}
	}
	//fmt.Printf("RESULT2: %#v -- %#v\n", results, err)
	if len(results) > 0 {
		if attrib := results[0].Attribute("style"); attrib != nil {
			styleContent := attrib.Value()
			codedImageURL := regexStyleImage.FindString(styleContent)
			genURL := strings.ReplaceAll(codedImageURL, `\3a `, `:`)
			genURL = strings.ReplaceAll(genURL, `\3d `, `=`)
			genURL = strings.ReplaceAll(genURL, `\26 `, `&`)
			genURL = strings.ReplaceAll(genURL, `\25 `, `%`)
			genURL = strings.TrimPrefix(genURL, `url('`)
			genURL = strings.TrimSuffix(genURL, `');`)
			return genURL, nil

		}
	}
	return "", errors.New("cannot find image url")
	//s := QuerySelector(doc, "img.scaledImageFitHeight")
	//if s.Length() == 0 {
	//	s = QuerySelector(doc, "img.scaledImageFitWidth")
	//}
	//
	//url, ok := s.Attr("src")
	//if !ok {
	//	return "", errors.New("cannot find image url")
	//}
	//
	//return url, nil
}

// GetGiftURL GetGiftURL
func GetGiftURL(htmlNode gokogirixml.Node) (string, error) {

	//s := QuerySelector(doc, "div._6ks > a")
	//
	//url, ok := s.Attr("href")

	results, err := htmlNode.Search(xPathGiftURL)
	if err != nil {
		// search for the second possible image
		results, err = htmlNode.Search(xPathImageURL2)
		if err != nil {
			return "", err
		}
	}

	var genURL string
	var attrib *gokogirixml.AttributeNode
	if len(results) > 0 {
		attrib = results[0].Attribute("href")
		if attrib != nil {
			tmpGiftURL := attrib.Value()
			tmpGiftURL = html.UnescapeString(tmpGiftURL)
			tmpGiftURL2, err := url.Parse(tmpGiftURL)
			if err != nil {
				attrib = nil
				goto nextGiftLinkChecker
			}

			//fmt.Printf("%#v\n", tmpGiftURL2)

			newQuery := url.Values{}
			oldQuery := tmpGiftURL2.Query()
			newQuery.Set("nx_source", oldQuery.Get("nx_source"))
			newQuery.Set("gift_id", oldQuery.Get("gift_id"))

			tmpURLGen := url.URL{
				Scheme:   tmpGiftURL2.Scheme,
				Host:     tmpGiftURL2.Host,
				Path:     tmpGiftURL2.Path,
				RawQuery: newQuery.Encode(),
			}
			if tmpURLGen.Scheme != "https" {
				tmpURLGen.Scheme = "https"
			}
			genURL = tmpURLGen.String()
		}
	}
nextGiftLinkChecker:
	if attrib == nil {
		results, err := htmlNode.Search(xPathArticleContent)
		if err != nil {
			return "", err
		}
		if len(results) > 0 {
			//TODO: Fix and check all URLs
			rxRelaxed := xurls.Relaxed()
			genURL = rxRelaxed.FindString(results[0].Content())
		}
	}

	if len(genURL) == 0 {
		return "", errors.New("cannot find gift url")
	}
	//fmt.Printf("%#v\n", genURL)
	resultURL, err := ExpandURL2(genURL, fbGameURL)
	if err != nil {
		return "", errors.New("cannot find gift url - ExpandURL2")
	}

	return resultURL, nil
}

// GetPostURL GetPostURL
func GetPostURL(htmlNode gokogirixml.Node) (string, error) {

	//s := QuerySelector(doc, "a._5pcq")
	//
	//url, ok := s.Attr("href")
	//if !ok {
	//	//TODO: Fix and check all URLs
	//	rxRelaxed := xurls.Relaxed()
	//	url = rxRelaxed.FindString(doc.Text())
	//
	//	if len(url) == 0 {
	//		return "", errors.New("cannot find post url")
	//	}
	//} else {
	//	url = "https://www.facebook.com" + url
	//}
	results, err := htmlNode.Search(xPathPostingURL)
	if err != nil {
		return "", err
	}

	var genURL string
	var attrib *gokogirixml.AttributeNode
	if len(results) > 0 {
		attrib = results[0].Attribute("href")
		//fmt.Printf("%#v\n\n", attrib)
		if attrib != nil {
			tmpPostURL := attrib.Value()
			//fmt.Printf("%#v\n", tmpPostURL)
			tmpPostURL = html.UnescapeString(tmpPostURL)
			//fmt.Printf("%#v\n", tmpPostURL)
			tmpPostURL2, err := url.Parse(tmpPostURL)
			//fmt.Printf("%#v -- %#v\n", tmpPostURL2, err)
			if err != nil {
				attrib = nil
				goto nextPostLinkChecker
			}

			//fmt.Printf("%#v\n", tmpPostURL2)

			newQuery := url.Values{}
			oldQuery := tmpPostURL2.Query()
			newQuery.Set("nx_source", oldQuery.Get("nx_source"))
			newQuery.Set("gift_id", oldQuery.Get("gift_id"))

			tmpURLGen := url.URL{
				Scheme: tmpPostURL2.Scheme,
				Host:   tmpPostURL2.Host,
				Path:   `herowarsgame/posts/` + dataFT.TopLevelPostID,
			}
			if tmpURLGen.Scheme != "https" {
				tmpURLGen.Scheme = "https"
			}
			if tmpURLGen.Host != "www.facebook.com" {
				tmpURLGen.Host = "www.facebook.com"
			}

			//			dataFT.

			genURL = tmpURLGen.String()
		}
		//fmt.Printf("GENURL: %#v\n", genURL)
	}
nextPostLinkChecker:

	resultURL, err := ExpandURL2(genURL, fbPageURL)
	if err != nil {
		return "", errors.New("cannot find post url - ExpandURL2")
	}

	return resultURL, nil
}

type object interface {
	Find(string) *goquery.Selection
}

// QuerySelector QuerySelector
func QuerySelector(s object, selector string) *goquery.Selection {
	return s.Find(selector).First()
}

// QuerySelectorEach QuerySelectorEach
func QuerySelectorEach(s object, selector string, mf func(i int, selection *goquery.Selection)) *goquery.Selection {
	return s.Find(selector).Each(mf)
}

// ParseTimeStamp ParseTimeStamp
func ParseTimeStamp(utime int64) (string, error) {
	t := time.Unix(utime, 0)
	return t.Format(time.RFC3339), nil
}

// GetTimeStamp GetTimeStamp
func GetTimeStamp(htmlNode gokogirixml.Node) (string, error) {
	//s := QuerySelector(doc, "._5ptz.timestamp.livetimestamp")
	//s := QuerySelector(doc, "abbr._5ptz")

	results, err := htmlNode.Search(xPathArticle)
	if err != nil {
		return "", err
	}

	if attrib := results[0].Attribute("data-ft"); attrib != nil {
		json := attrib.Value()
		normalJSON := html.UnescapeString(json)
		dataFTinternal, err := UnmarshalDataFT([]byte(normalJSON))

		dataFT = &dataFTinternal

		if err != nil {

			return "", err
		}
		pid := dataFTinternal.PageID
		return ParseTimeStamp(dataFTinternal.PageInsights[pid].PostContext.PublishTime)

	}

	return "", errors.New("cannot find timestamp")
}

// ProfileLink ProfileLink
type ProfileLink struct {
	Name string
	URL  string
}

// GetProfileLink GetProfileLink
func GetProfileLink(doc *goquery.Document) (*ProfileLink, error) {
	s := QuerySelector(doc, "a.profileLink")
	if s.Length() == 0 {
		s = QuerySelector(doc, "span.fwb.fcg > a")
	}

	pl := ProfileLink{}

	pl.Name = s.Text()
	if pl.Name == "" {
		return nil, errors.New("cannot find name of profile link")
	}

	url, ok := s.Attr("href")
	if !ok {
		return nil, errors.New("cannot find url of profile link")
	}
	pl.URL = url

	return &pl, nil
}

// GetBlogspotTimeStamp GetBlogspotTimeStamp
func GetBlogspotTimeStamp(doc *goquery.Document) (string, error) {
	abbr := QuerySelector(doc, "a.timestamp-link > abbr")
	t, ok := abbr.Attr("title")
	if ok {
		return t, nil
	}

	return "", errors.New("cannot find timestamp")
}

// GetBlogspotTitle GetBlogspotTitle
func GetBlogspotTitle(doc *goquery.Document) (string, error) {
	t := QuerySelector(doc, "h3.post-title")
	return strings.TrimSpace(t.Text()), nil
}

//GetBlogspotContent GetBlogspotContent
func GetBlogspotContent(doc *goquery.Document) (string, error) {
	c := QuerySelector(doc, "div.post-body")

	s, err := c.Html()
	if err != nil {
		return "", err
	}

	var lines []string

	scanner := bufio.NewScanner(strings.NewReader(s))
	for scanner.Scan() {
		lines = append(lines, "  "+scanner.Text())
	}

	if err := scanner.Err(); err != nil {
		return "", err
	}

	return strings.Join(lines, "\n"), nil
}

//GetBlogspotURL GetBlogspotURL
func GetBlogspotURL(doc *goquery.Document) (string, error) {
	meta := QuerySelector(doc, "meta[property='og:url']")
	u, ok := meta.Attr("content")
	if ok {
		return u, nil
	}

	return "", errors.New("cannot find url")
}

// GetBlogspotSummary GetBlogspotSummary
func GetBlogspotSummary(doc *goquery.Document) (string, error) {
	meta := QuerySelector(doc, "meta[property='og:description']")
	d, ok := meta.Attr("content")
	if ok {
		return strings.TrimSpace(d), nil
	}

	return "", errors.New("cannot find summary")
}

// GetBlogspotAuthor GetBlogspotAuthor
func GetBlogspotAuthor(doc *goquery.Document) (string, error) {
	a := QuerySelector(doc, "span.post-author > span.fn")
	return a.Text(), nil
}

//GetBlogspotTags GetBlogspotTags
func GetBlogspotTags(doc *goquery.Document) (string, error) {
	s := doc.Find("span.post-labels > a")
	labels := ""
	s.Each(func(_ int, l *goquery.Selection) {
		if labels != "" {
			labels += ", "
		}
		labels += l.Text()
	})
	return labels, nil
}

// ParseBlogspotPost ParseBlogspotPost
func ParseBlogspotPost(doc *goquery.Document) (*FBPostData, error) {
	bs := FBPostData{}
	var err error

	bs.TimeStamp, err = GetBlogspotTimeStamp(doc)
	if err != nil {
		return &bs, err
	}

	bs.Title, err = GetBlogspotTitle(doc)
	if err != nil {
		return &bs, err
	}

	bs.Content, err = GetBlogspotContent(doc)
	if err != nil {
		return &bs, err
	}

	bs.PostURL, err = GetBlogspotURL(doc)
	if err != nil {
		return &bs, err
	}

	bs.Summary, err = GetBlogspotSummary(doc)
	if err != nil {
		return &bs, err
	}

	bs.Author, err = GetBlogspotAuthor(doc)
	if err != nil {
		return &bs, err
	}

	bs.Tags, err = GetBlogspotTags(doc)
	if err != nil {
		return &bs, err
	}

	return &bs, nil
}