Added walk utils api

utils/walk.go

@@ -0,0 +1,210 @@
+package utils
+
+import (
+	"fmt"
+	"github.com/ByteDream/crunchyroll-go"
+)
+
+// EpisodeWalker is an easy-to-use struct which walks down given urls
+// and triggers functions where you can perform further actions with
+// the delivered objects
+type EpisodeWalker struct {
+	// The Crunchyroll instance to perform all actions on
+	Crunchyroll *crunchyroll.Crunchyroll
+
+	// If CheckDuplicates is true, duplicated urls, seasons and episodes
+	// are filtered out and the values given in OnSeason for example is
+	// always unique
+	CheckDuplicates bool
+
+	// OnUrl gets called when an url is parsed.
+	// The error is generally only nil when the url is invalid
+	OnUrl func(url string, err error) error
+	// OnSeason gets called when a season was parsed
+	OnSeason func(season *crunchyroll.Season, err error) error
+	// OnEpisode gets called when a season was parsed
+	OnEpisode func(episode *crunchyroll.Episode, err error) error
+}
+
+// WalkURLs walks through all urls.
+// Urls to seasons and episodes are support, normal as well as beta urls
+func (ew EpisodeWalker) WalkURLs(urls []string) error {
+	var episodeIds, seasonIds, seriesNames []string
+	var episodeNames map[string][]string
+
+	for _, url := range urls {
+		if episodeId, ok := crunchyroll.ParseBetaEpisodeURL(url); ok && !(ew.CheckDuplicates && sliceContains(episodeIds, episodeId)) {
+			episodeIds = append(episodeIds, episodeId)
+		} else if seasonId, ok := crunchyroll.ParseBetaSeriesURL(url); ok && !(ew.CheckDuplicates && sliceContains(seasonIds, seasonId)) {
+			seasonIds = append(seasonIds, seasonId)
+		} else if seriesName, title, _, _, ok := crunchyroll.ParseEpisodeURL(url); ok {
+			if eps, ok := episodeNames[seriesName]; ok {
+				if !ew.CheckDuplicates || !sliceContains(eps, title) {
+					eps = append(eps, title)
+				}
+			} else {
+				episodeNames[seriesName] = []string{title}
+			}
+		} else if seriesName, ok := crunchyroll.ParseVideoURL(url); ok && !(ew.CheckDuplicates && sliceContains(seriesNames, seriesName)) {
+			seriesNames = append(seriesNames, seriesName)
+		} else {
+			err := fmt.Errorf("invalid url %s", url)
+			if ew.OnUrl != nil {
+				if err = ew.OnUrl(url, err); err != nil {
+					return err
+				}
+				continue
+			} else {
+				return err
+			}
+		}
+
+		if ew.OnUrl != nil {
+			if err := ew.OnUrl(url, nil); err != nil {
+				return err
+			}
+		}
+	}
+
+	for _, name := range seriesNames {
+		video, err := ew.Crunchyroll.FindVideoByName(name)
+		if err != nil {
+			return err
+		}
+		// in all cases i've ever tested video was a series - even
+		// if it was listed as a movie on the crunchyroll website.
+		// i just hope no error occurs here :)
+		seasons, err := video.(*crunchyroll.Series).Seasons()
+		if err != nil {
+			return err
+		}
+		for _, season := range seasons {
+			if ew.CheckDuplicates {
+				if sliceContains(seasonIds, season.ID) {
+					continue
+				}
+				seasonIds = append(seasonIds, season.ID)
+			}
+			if ew.OnSeason != nil {
+				if err := ew.OnSeason(season, nil); err != nil {
+					return err
+				}
+			}
+		}
+	}
+
+	if err := ew.walkEpisodeIds(episodeIds); err != nil {
+		return err
+	} else if err := ew.walkSeasonIds(seasonIds); err != nil {
+		return err
+	} else if err := ew.walkEpisodeNames(episodeNames); err != nil {
+		return err
+	}
+	return nil
+}
+
+func (ew EpisodeWalker) walkEpisodeIds(episodeIds []string) error {
+	var episodeIdsCheck []string
+
+	for _, id := range episodeIds {
+		if ew.CheckDuplicates {
+			if sliceContains(episodeIdsCheck, id) {
+				continue
+			}
+			episodeIdsCheck = append(episodeIdsCheck, id)
+		}
+
+		episode, err := crunchyroll.EpisodeFromID(ew.Crunchyroll, id)
+		if ew.OnEpisode != nil {
+			if err = ew.OnEpisode(episode, err); err != nil {
+				return err
+			}
+		}
+	}
+	return nil
+}
+
+func (ew EpisodeWalker) walkSeasonIds(seasonIds []string) error {
+	var episodeIdsCheck []string
+
+	for _, id := range seasonIds {
+		season, err := crunchyroll.SeasonFromID(ew.Crunchyroll, id)
+		if ew.OnSeason != nil {
+			if err = ew.OnSeason(season, err); err != nil {
+				return err
+			}
+		} else if err != nil {
+			return err
+		}
+		eps, err := season.Episodes()
+		if err != nil {
+			return err
+		}
+		for _, ep := range eps {
+			if ew.CheckDuplicates {
+				if sliceContains(episodeIdsCheck, ep.ID) {
+					continue
+				}
+				episodeIdsCheck = append(episodeIdsCheck, ep.ID)
+			}
+
+			if ew.OnEpisode != nil {
+				if err = ew.OnEpisode(ep, nil); err != nil {
+					return err
+				}
+			}
+		}
+	}
+	return nil
+}
+
+func (ew EpisodeWalker) walkEpisodeNames(episodeNames map[string][]string) error {
+	var episodeIdsCheck []string
+
+	for seriesName, episodeName := range episodeNames {
+		video, err := ew.Crunchyroll.FindVideoByName(seriesName)
+		if err != nil {
+			return err
+		}
+		series := video.(*crunchyroll.Series)
+		seasons, err := series.Seasons()
+		if err != nil {
+			return err
+		}
+		for _, season := range seasons {
+			eps, err := season.Episodes()
+			if err != nil {
+				return err
+			}
+			for _, ep := range eps {
+				for _, name := range episodeName {
+					if ep.SlugTitle == name {
+						if ew.OnEpisode != nil {
+							if ew.CheckDuplicates {
+								if sliceContains(episodeIdsCheck, ep.ID) {
+									continue
+								}
+								episodeIdsCheck = append(episodeIdsCheck, ep.ID)
+							}
+
+							if err = ew.OnEpisode(ep, nil); err != nil {
+								return err
+							}
+						}
+						break
+					}
+				}
+			}
+		}
+	}
+	return nil
+}
+
+func sliceContains(slice []string, elem string) bool {
+	for _, s := range slice {
+		if elem == s {
+			return true
+		}
+	}
+	return false
+}