package metadata

import (
	"context"

	"github.com/Silo-Server/silo-server/internal/models"
)

// RefreshMode determines how the pipeline processes an item.
type RefreshMode int

const (
	ModeInitialMatch     RefreshMode = iota // New file discovered by scanner
	ModeScheduledRefresh                    // Background periodic refresh
	ModeManualRefresh                       // User-triggered refresh
	ModeIdentify                            // User manually identified item
)

// MergeMode determines how provider results merge into existing items.
type MergeMode int

const (
	MergeFillEmpty       MergeMode = iota // Only fill zero/empty fields
	MergeReplaceUnlocked                  // Replace all unlocked fields
)

// MetadataField identifies a lockable metadata field.
type MetadataField int

const (
	FieldName MetadataField = iota
	FieldOverview
	FieldGenres
	FieldStudios
	FieldCast
	FieldCrew
	FieldRating
	FieldRuntime
	FieldTags
	FieldContentRating
	FieldImages
	FieldAirSchedule
	FieldVideos
	// FieldReleaseDates locks Year, ReleaseDate, and First/LastAirDate so a
	// refresh (or an NFO at priority 1) cannot overwrite manual corrections.
	FieldReleaseDates
)

// RefreshPriority controls queue ordering.
type RefreshPriority int

const (
	PriorityHigh   RefreshPriority = 0 // Manual refresh, identify
	PriorityNormal RefreshPriority = 1 // Newly matched items
	PriorityLow    RefreshPriority = 2 // Scheduled background refresh
)

// ProcessRequest is the unified input to MetadataService.Process().
type ProcessRequest struct {
	ContentID   string            // Existing item (refresh/identify) or empty (new match)
	Hints       *MatchHints       // From scanner (initial match only)
	ProviderIDs map[string]string // From user selection (identify only)
	FolderID    string            // Which library folder
	Language    string            // ISO 639-1 metadata language (resolved from folder)
	Mode        RefreshMode
	// AdoptLanguage makes Language the item's new canonical metadata
	// language: the base row is rewritten in Language and
	// default_metadata_language is restamped, instead of routing a
	// non-canonical language to the localization tables. Set by
	// folder-scoped manual refreshes when the library's configured
	// language differs from the item's stamp, so changing a library's
	// metadata language actually re-fetches titles/overviews.
	AdoptLanguage            bool
	recordedStaleProviderIDs providerIDValueSet
}

// ProcessResult is the output of MetadataService.Process().
type ProcessResult struct {
	ContentID string
	IsNew     bool // True if this was an initial match (new item created)
	Updated   bool // True if any fields were changed
	Decision  *MatchDecision
}

// MatchDecision is a bounded, persistence-safe explanation of an automatic
// matcher outcome. It intentionally excludes artwork and provider payloads.
type MatchDecision struct {
	Outcome        MatchOutcome             `json:"outcome"`
	CandidateCount int                      `json:"candidate_count"`
	Threshold      float64                  `json:"threshold"`
	TopCandidates  []MatchDecisionCandidate `json:"top_candidates,omitempty"`
}

type MatchDecisionCandidate struct {
	Title        string            `json:"title"`
	MatchedTitle string            `json:"matched_title,omitempty"`
	Year         int               `json:"year,omitempty"`
	ProviderIDs  map[string]string `json:"provider_ids,omitempty"`
	Sources      []string          `json:"sources,omitempty"`
	Score        float64           `json:"score"`
	Reasons      []string          `json:"reasons,omitempty"`
}

type MatchFailure struct {
	Kind     MatchOutcome
	Message  string
	Decision *MatchDecision
}

// MatchOutcome is the stable matcher/queue failure taxonomy exposed in
// bounded diagnostics. Keep additions backward-compatible with persisted
// failure_kind values and the admin API.
type MatchOutcome string

const (
	MatchOutcomeMatched               MatchOutcome = "matched"
	MatchOutcomeNoCandidates          MatchOutcome = "no_candidates"
	MatchOutcomeCandidateRejected     MatchOutcome = "candidate_rejected"
	MatchOutcomeTrustedIDConflict     MatchOutcome = "trusted_id_conflict"
	MatchOutcomeTrustedIDTypeMismatch MatchOutcome = "trusted_id_type_mismatch"
	MatchOutcomeMetadataEmpty         MatchOutcome = "metadata_empty"
	MatchOutcomeProviderTransient     MatchOutcome = "provider_transient"
	MatchOutcomeProviderPermanent     MatchOutcome = "provider_permanent"
)

// MatchHints carries scanner-extracted data into the pipeline.
// Adapted from matcher.MatchHints with FilePath added for local providers.
type MatchHints struct {
	ContentID                 string
	FileHash                  string
	TmdbID                    string
	TvdbID                    string
	ImdbID                    string
	Title                     string
	Year                      int
	Type                      string // "movie" or "series"
	SeasonNum                 int
	EpisodeNum                int
	HintSource                string // "xattr", "nfo", "folder", "filename"
	FilePath                  string // Absolute path to media file (legacy local-provider field)
	RepresentativeFilePath    string
	ObservedRootPath          string
	AllGroupFilePaths         []string
	PrimarySidecarSearchPaths []string
	// AlternateIdentities are independently parsed title/year hypotheses from
	// the filename and surrounding directories. They are tried only after the
	// primary scanner identity fails, keeping provider traffic bounded while
	// allowing a good filename to recover from a stale or release-like folder.
	AlternateIdentities []MatchIdentityHint
}

type MatchIdentityHint struct {
	Title  string
	Year   int
	Source string
}

// SearchQuery is passed to SearchProvider.Search().
type SearchQuery struct {
	Title                     string
	Author                    string // optional creator hint (e.g. ebook author) folded into the search query
	Year                      int
	ContentType               string            // media_items.type value
	ProviderIDs               map[string]string // Accumulated IDs from prior providers
	Language                  string            // ISO 639-1 code from library preference
	FilePath                  string
	RepresentativeFilePath    string
	ObservedRootPath          string
	AllGroupFilePaths         []string
	PrimarySidecarSearchPaths []string
}

// SearchResult is returned from SearchProvider.Search().
type SearchResult struct {
	Name             string
	OriginalTitle    string
	TitleAliases     []TitleAlias
	TitleLanguage    string
	TitleIsFallback  bool
	OriginalLanguage string
	Year             int
	ProviderIDs      map[string]string
	ImageURL         string
	Overview         string
	Provider         string // Slug of the provider that returned this
}

// TitleAlias is a provider-confirmed title for the same work.
type TitleAlias struct {
	Title    string `json:"title"`
	Language string `json:"language,omitempty"`
	Kind     string `json:"kind"`
	Provider string `json:"provider,omitempty"`
}

const (
	titleAliasKindOriginal  = "original"
	titleAliasKindLocalized = "localized"
	matchContentTypeMovie   = "movie"
	matchContentTypeSeries  = "series"
)

// MetadataRequest is passed to MetadataProvider.GetMetadata().
type MetadataRequest struct {
	ProviderIDs               map[string]string
	ContentType               string
	Language                  string
	FilePath                  string // Populated for local providers, empty for remote
	RepresentativeFilePath    string
	ObservedRootPath          string
	AllGroupFilePaths         []string
	PrimarySidecarSearchPaths []string
	GroupTitle                string
	GroupYear                 int
}

// PersonDetailRequest is passed to person detail lookups.
type PersonDetailRequest struct {
	ProviderIDs map[string]string
	Language    string
}

// PersonDetailResult carries person-level metadata from a provider.
type PersonDetailResult struct {
	Name            string
	SortName        string
	Bio             string
	BirthDate       string
	DeathDate       string
	Birthplace      string
	Homepage        string
	PhotoPath       string
	PhotoSourcePath string
	PhotoThumbhash  string
	ProviderIDs     map[string]string
}

// MetadataResult carries structured metadata from a single provider.
type MetadataResult struct {
	HasMetadata          bool
	ProviderIDs          map[string]string
	Title                string
	OriginalTitle        string
	SortTitle            string
	Overview             string
	Tagline              string
	Year                 int
	Runtime              int
	Genres               []string
	Studios              []string
	Networks             []string
	Countries            []string
	Keywords             []string
	OriginalLanguage     string
	TitleAliases         []TitleAlias
	TitleAliasesComplete bool
	TitleLanguage        string
	TitleIsFallback      bool
	// titleAliasProviders records whether each contributing provider declared
	// its aliases to be an authoritative snapshot. False means merge-only,
	// which is the safe default for legacy plugins and partial responses.
	titleAliasProviders map[string]bool
	// quarantinedProviderIDKeys prevents unresolved conflicting IDs from being
	// reintroduced by later provider details or durable merge.
	quarantinedProviderIDKeys map[string]struct{}
	// replacedProviderIDKeys forces an owning-provider consensus replacement to
	// overwrite the corresponding stored provider-ID column during merge.
	replacedProviderIDKeys map[string]struct{}
	// recordedStaleProviderIDs contains provider values known dead before this
	// refresh and suppresses them when durable state is merged.
	recordedStaleProviderIDs providerIDValueSet
	// sameRunStaleProviderIDs contains identity values that 404ed during this
	// refresh and prevents them from being persisted by the same operation.
	sameRunStaleProviderIDs providerIDValueSet
	ContentRating           string
	Ratings                 Ratings
	People                  []models.ItemPerson
	// Images (S3 paths or URLs).
	PosterPath        string
	PosterThumbhash   string
	BackdropPath      string
	BackdropThumbhash string
	LogoPath          string
	// Series-specific
	ReleaseDate  string
	SeasonCount  int
	FirstAirDate string
	LastAirDate  string
	AirTime      string
	AirTimezone  string
	// ShowStatus is the publication/airing status ("Ongoing", "Completed",
	// "Continuing", "Ended") when the provider reports one.
	ShowStatus string
	// Videos are remote promotional/supplemental videos (trailers, teasers,
	// ...) hosted on external sites. Accumulated across providers with
	// (Provider, ProviderKey) dedup, gated by FieldVideos and the library's
	// trailer_kinds allow-list at persist time.
	Videos []RemoteVideo
}

// RemoteVideo describes a provider-reported external video (YouTube trailer
// etc.). It mirrors the SDK's VideoRecord and persists as an item_videos row.
type RemoteVideo struct {
	Provider    string // provider slug that returned this video
	ProviderKey string // provider-native video id (dedup key)
	Kind        models.ExtraKind
	Site        string // hosting site, e.g. "youtube"
	SiteKey     string // site-native video key (YouTube video id)
	Name        string
	Language    string // ISO 639-1, empty when unknown
	IsOfficial  bool
	SizeHint    int    // vertical resolution hint (e.g. 1080), 0 when unknown
	PublishedAt string // RFC 3339, empty when unknown
}

// Ratings holds ratings from multiple sources.
type Ratings struct {
	IMDB       float64
	TMDB       float64
	RTCritic   float64
	RTAudience float64
}

// ImageRequest is passed to ImageProvider.GetImages().
type ImageRequest struct {
	ProviderIDs map[string]string
	ContentType string
	Language    string
	// Local sidecar context (additive; empty for purely remote providers).
	// RepresentativeFilePath is the group's representative media file,
	// AllGroupFilePaths are every file in the content group, and
	// PrimarySidecarSearchPaths are directories already validated as safe for
	// directory-level sidecars (single-content observed roots).
	RepresentativeFilePath    string
	AllGroupFilePaths         []string
	PrimarySidecarSearchPaths []string
}

// RemoteImage describes an available image from a provider.
type RemoteImage struct {
	ProviderID string // Slug of the provider that returned this image
	URL        string
	Type       ImageType
	Language   string
	Width      int
	Height     int
	Rating     float64 // Vote average for ordering
}

// ImageType classifies image purpose.
type ImageType int

const (
	ImagePoster ImageType = iota
	ImageBackdrop
	ImageLogo
	ImageStill // Episode stills
	ImageProfile
)

// CacheImageRequest describes an image to be cached. For season posters
// and episode stills, ContentID is the parent series's ID and the
// SeasonNumber / EpisodeNumber fields scope the S3 key so siblings do not
// collide. Both pointers are nil for item-level images.
type CacheImageRequest struct {
	SourceURL     string
	ProviderID    string
	ContentType   string // "movies" or "series"
	ContentID     string
	ImageType     ImageType
	SeasonNumber  *int
	EpisodeNumber *int
	Language      string
	// KeyDiscriminator, when set, is inserted into the S3 key between the
	// content ID and the image type (e.g. the 8-hex content hash of a local
	// sidecar file) so re-cached art rotates to a fresh key.
	KeyDiscriminator string
}

// CacheImageResult is returned by ImageCacher on success.
type CacheImageResult struct {
	BasePath     string // image-type prefix retained for legacy callers
	OriginalPath string // exact immutable original-variant object key
	Revision     string // content revision shared by all generated variants
	Thumbhash    string // base64-encoded
	Ext          string // encoded file extension including dot

	UploadedVariants int
	ExistingVariants int
}

// ImageCacher caches a remote image to object storage.
type ImageCacher interface {
	CacheImage(ctx context.Context, req CacheImageRequest) (*CacheImageResult, error)
}

// ImageByteCacher caches an image already read into memory (e.g. a local
// sidecar file) to object storage. Implemented by imagecache.Cacher alongside
// ImageCacher; the processor type-asserts it for file:// sources.
type ImageByteCacher interface {
	CacheImageBytes(ctx context.Context, data []byte, req CacheImageRequest) (*CacheImageResult, error)
}

type ImageCacheJobEnqueuer interface {
	Enqueue(ctx context.Context, in EnqueueImageCacheJobInput) error
	EnqueueBatch(ctx context.Context, inputs []EnqueueImageCacheJobInput) (int, error)
}

// SeasonsRequest is passed to EpisodeProvider.GetSeasons().
type SeasonsRequest struct {
	ProviderIDs map[string]string
	ContentType string
	Language    string
	// Local sidecar context (additive, internal — mirrors MetadataRequest).
	// SeriesRootPaths are directories already validated as safe for
	// directory-level sidecars (the series root); SeasonDirectoryPaths maps
	// each directory-derived season number to its candidate directories.
	// Both are empty for purely remote providers, which key off ProviderIDs.
	SeriesRootPaths      []string
	SeasonDirectoryPaths map[int][]string
}

// EpisodesRequest is passed to EpisodeProvider.GetEpisodes().
type EpisodesRequest struct {
	ProviderIDs  map[string]string
	SeasonNumber int
	Language     string
	// Local sidecar context (additive, internal). SeriesRootPaths as on
	// SeasonsRequest; EpisodeFilePaths maps each filename-derived episode
	// number within SeasonNumber to that episode's media file paths.
	SeriesRootPaths  []string
	EpisodeFilePaths map[int][]string
}

// SeasonResult carries season data from a provider.
type SeasonResult struct {
	ContentID        string
	SeasonNumber     int
	Title            string
	Overview         string
	AirDate          string
	PosterPath       string
	PosterSourcePath string
	PosterThumbhash  string
	Episodes         []EpisodeResult
}

// EpisodeResult carries episode data from a provider.
type EpisodeResult struct {
	ContentID       string
	ProviderIDs     map[string]string
	SeasonNumber    int
	EpisodeNumber   int
	Title           string
	Overview        string
	AirDate         string
	Runtime         int
	Ratings         Ratings
	StillPath       string
	StillSourcePath string
	StillThumbhash  string
}