package ytdlp

import (
	"context"
	"fmt"
	"strings"
	"time"

	"codeberg.org/danjones000/my-log/files"
	"codeberg.org/danjones000/my-log/models"
	ytd "github.com/lrstanley/go-ytdlp"
)

// Drop adds the URL specified by the url to the watched log.
func Drop(ctx context.Context, url string) (models.Log, error) {
	var ent models.Entry
	var log models.Log
	if ctx.Err() != nil {
		return log, context.Cause(ctx)
	}

	info, err := Fetch(ctx, url)
	if err != nil {
		return log, err
	}
	now := time.Now()
	ent.Date = now

	metas := &ent.Fields
	*metas = metas.Set("id", getID(now, info))

	source := FirstNonZero(info.ExtractorKey, info.WebpageURLDomain, new("Web Video"))
	*metas = metas.Set("source", source)

	ent.Title = FirstNonZero(info.Title, info.AltTitle, new(fmt.Sprintf("%s %s", source, info.ID)))

	setNote(metas, info)
	setArtist(metas, info)
	setTags(metas, info)
	setUrl(metas, info, url)

	// TODO Add show info

	log = models.Log{Name: "watched", Entries: []models.Entry{ent}}
	if err := files.Append(log); err != nil {
		return log, err
	}

	return log, nil
}

func getID(now time.Time, info *ytd.ExtractedInfo) string {
	id := new(strings.Builder)
	id.WriteString("tag:")
	id.WriteString(FirstNonZero(info.WebpageURLDomain, new("goodevilgenius.org")))
	id.WriteByte(',')
	id.WriteString(now.Format("2006"))
	id.WriteRune(':')
	id.WriteString(info.ID)
	id.WriteRune('/')
	fmt.Fprintf(id, "%d", now.Unix())
	return id.String()
}

func setNote(metas *models.Metas, info *ytd.ExtractedInfo) {
	desc := FirstNonZero(info.Description)
	if desc != "" {
		desc = strings.SplitN(desc, "\n", 2)[0]
		*metas = metas.Set("note", desc)
	}
}

func setArtist(metas *models.Metas, info *ytd.ExtractedInfo) {
	art := FirstNonZero(info.Artist, info.AlbumArtist, info.Uploader)
	if art != "" {
		*metas = metas.Set("artist", art)
	}
}

func setTags(metas *models.Metas, info *ytd.ExtractedInfo) {
	tags := make([]any, 0, len(info.Tags)+len(info.Categories))
	for _, t := range info.Tags {
		tags = append(tags, t)
	}
	for _, c := range info.Categories {
		tags = append(tags, c)
	}
	if len(tags) > 0 {
		*metas = metas.Set("tags", tags)
	}
}

func setDuration(metas *models.Metas, info *ytd.ExtractedInfo) {
	dur := FirstNonZero(info.Duration)
	if dur > 0 {
		*metas = metas.Set("duration", dur)
	}
}

func setUrl(metas *models.Metas, info *ytd.ExtractedInfo, origUrl string) {
	url := FirstNonZero(info.WebpageURL, info.PageURL, info.URL, &origUrl)
	*metas = metas.Set("url", url)
}

func FirstNonZero[T comparable](vals ...*T) T {
	var z T
	for _, v := range vals {
		if v != nil && *v != z {
			return *v
		}
	}
	return z
}