package nomad

import (
	"bytes"
	"errors"
	"fmt"
	"net/url"
	"path/filepath"

	"git.sr.ht/~thrrgilag/woodstock"
	"git.wntrmute.dev/kyle/goutils/log"
	"github.com/anaskhan96/soup"
)

func nomadLink(src Source) string {
	u, err := url.Parse(src.ID())
	if err != nil {
		log.Errf("nomadLink: %s", err)
		return fmt.Sprintf("[%s](%s)", src.ID(), src.ID())
	}

	return fmt.Sprintf("[%s](%s)", u.Host, src.ID())
}

type sel struct {
	selectors []string
}

func selector(selectors ...string) sel {
	return sel{selectors: selectors}
}

type imageFinder func(soup.Root) (string, bool)

var imageFinders = []imageFinder{
	func(root soup.Root) (string, bool) {
		return find(
			root, "src",
			selector("div", "class", "entry-image"),
			selector("img"))
	},
	func(root soup.Root) (string, bool) {
		return find(
			root, "src",
			selector("div", "class", "gh-inner"),
			selector("img"))
	},
}

func find(root soup.Root, attr string, selectors ...sel) (string, bool) {
	result := root
	for _, selector := range selectors {
		result = result.Find(selector.selectors...)
		if result.Pointer == nil {
			return "", false
		}
	}

	if attr == "" {
		text := result.Text()
		return text, text != ""
	}

	value, hasAttr := result.Attrs()[attr]
	return value, hasAttr
}

type Post struct {
	Image Source
	Body  string
	URL   Source
}

func NewPost(item Item) Post {
	return Post{
		Body: nomadLink(item.URL),
		URL:  item.URL,
	}
}

func (p *Post) Fetch() error {
	pageSource, err := p.URL.Fetch()
	if err != nil {
		return err
	}

	root := soup.HTMLParse(pageSource)
	body, hasBody := find(root, "", selector("p", "class", "entry-body"))
	if hasBody {
		p.Body = body + " " + p.Body
	}

	var imageURL string
	var hasImageURL bool

	for _, finder := range imageFinders {
		imageURL, hasImageURL = finder(root)
		if hasImageURL {
			break
		}
	}

	if hasImageURL {
		p.Image = NewURLSource(imageURL)
	}

	return nil
}

func (p Post) Post(client *woodstock.Client) error {
	pnutPost := woodstock.NewPost{
		Text: p.Body,
	}

	if p.Image != nil {
		imageData, err := p.Image.FetchBytes()
		if err != nil {
			return err
		}

		params := map[string]string{
			"name":      filepath.Base(p.Image.ID()),
			"is_public": "1",
			"type":      "photo",
		}

		r := bytes.NewBuffer(imageData)
		file, err := client.CreateFile(params, r)
		if err != nil {
			panic(err.Error())
			return err
		}
		pnutPost.Raw = []woodstock.Raw{pnutOembedRaw(file)}
	}

	result, err := client.Post(pnutPost)
	if err != nil {
		return err
	}

	if result.Meta.ErrorMessage != "" {
		return errors.New("woodstock: " + result.Meta.ErrorMessage)
	}
	return nil
}

func pnutOembedRaw(file woodstock.FileResult) woodstock.Raw {
	fval := map[string]string{
		"file_id":    file.Data.ID,
		"file_token": file.Data.FileToken,
		"format":     "oembed",
	}

	value := map[string]map[string]string{"+io.pnut.core.file": fval}
	return woodstock.Raw{Type: "io.pnut.core.oembed", Value: value}
}