package web

import (
	"context"
	"sort"
	"time"

	"gitea.kazu634.com/kazu634/tver/internal/store"
	"github.com/jackc/pgx/v5"
)

type fakeJobStore struct {
	jobs                      map[string]store.Job
	subscriptions             map[string]store.Subscription
	nextID                    int64
	lastEpisode               store.Episode
	enqueueCalls, statusCalls int
	statusIDs                 []string
	listStatuses              []string
	listLimits                []int
	registerCalls             int
	registerEpisodes          []store.Episode
	registerDownload          bool
	registerErr               error
	subscribedCalls           int
	subscribedIDs             []string
	beforeDeleteSucceeded     func()
	err                       error
}

func (f *fakeJobStore) ensure() {
	if f.jobs == nil {
		f.jobs = make(map[string]store.Job)
	}
}

func (f *fakeJobStore) Enqueue(_ context.Context, ep store.Episode, source string) (store.Job, bool, error) {
	f.enqueueCalls++
	f.lastEpisode = ep
	if f.err != nil {
		return store.Job{}, false, f.err
	}
	f.ensure()
	if job, ok := f.jobs[ep.ID]; ok {
		return job, false, nil
	}
	f.nextID++
	job := store.Job{ID: f.nextID, EpisodeID: ep.ID, SeriesTitle: ep.SeriesTitle,
		Title: ep.Title, BroadcasterName: ep.BroadcasterName, Source: source,
		Status: "queued", CreatedAt: time.Date(2026, 10, 3, 0, 0, 0, 0, time.UTC)}
	f.jobs[ep.ID] = job
	return job, true, nil
}

func (f *fakeJobStore) EpisodeStatuses(_ context.Context, ids []string) (map[string]string, error) {
	f.statusCalls++
	f.statusIDs = append([]string(nil), ids...)
	if f.err != nil {
		return nil, f.err
	}
	result := make(map[string]string)
	for _, id := range ids {
		if job, ok := f.jobs[id]; ok {
			result[id] = job.Status
		}
	}
	return result, nil
}

func (f *fakeJobStore) ListJobs(_ context.Context, status string, limit int) ([]store.Job, error) {
	f.listStatuses = append(f.listStatuses, status)
	f.listLimits = append(f.listLimits, limit)
	if f.err != nil {
		return nil, f.err
	}
	var result []store.Job
	for _, job := range f.jobs {
		if job.Status == status {
			result = append(result, job)
		}
	}
	sort.Slice(result, func(i, j int) bool { return result[i].ID > result[j].ID })
	if len(result) > limit {
		result = result[:limit]
	}
	return result, nil
}

func (f *fakeJobStore) GetJob(_ context.Context, id int64) (store.Job, error) {
	if f.err != nil {
		return store.Job{}, f.err
	}
	for _, job := range f.jobs {
		if job.ID == id {
			return job, nil
		}
	}
	return store.Job{}, pgx.ErrNoRows
}

func (f *fakeJobStore) Retry(_ context.Context, id int64) error {
	for ep, job := range f.jobs {
		if job.ID == id && (job.Status == "failed" || job.Status == "canceled") {
			job.Status = "queued"
			f.jobs[ep] = job
			return nil
		}
	}
	return store.ErrInvalidTransition
}

func (f *fakeJobStore) RetryEpisode(_ context.Context, id string) error {
	job, ok := f.jobs[id]
	if !ok || (job.Status != "failed" && job.Status != "canceled") {
		return store.ErrInvalidTransition
	}
	job.Status = "queued"
	f.jobs[id] = job
	return nil
}

func (f *fakeJobStore) Cancel(_ context.Context, id int64) error {
	if f.err != nil {
		return f.err
	}
	for ep, job := range f.jobs {
		if job.ID == id && (job.Status == "queued" || job.Status == "running") {
			job.Status = "canceled"
			f.jobs[ep] = job
			return nil
		}
	}
	return store.ErrInvalidTransition
}

func (f *fakeJobStore) CancelQueued(ctx context.Context, id int64) error {
	return f.Cancel(ctx, id)
}

var _ JobStore = (*fakeJobStore)(nil)

func (f *fakeJobStore) SubscribedSeries(_ context.Context, ids []string) (map[string]bool, error) {
	f.subscribedCalls++
	f.subscribedIDs = append([]string(nil), ids...)
	if f.err != nil {
		return nil, f.err
	}
	result := make(map[string]bool)
	for _, id := range ids {
		_, result[id] = f.subscriptions[id]
	}
	return result, nil
}

func (f *fakeJobStore) RegisterSubscription(_ context.Context, seriesID, title string, episodes []store.Episode, download bool) (bool, error) {
	f.registerCalls++
	f.registerEpisodes = append([]store.Episode(nil), episodes...)
	f.registerDownload = download
	if f.registerErr != nil {
		return false, f.registerErr
	}
	if f.err != nil {
		return false, f.err
	}
	if f.subscriptions == nil {
		f.subscriptions = make(map[string]store.Subscription)
	}
	if _, exists := f.subscriptions[seriesID]; exists {
		return false, nil
	}
	var count int64
	if download {
		count = int64(len(episodes))
	}
	checked := time.Date(2026, 10, 3, 0, 0, 0, 0, time.UTC)
	f.subscriptions[seriesID] = store.Subscription{SeriesID: seriesID, SeriesTitle: title,
		Enabled: true, CreatedAt: checked, LastCheckedAt: &checked, JobCount: count}
	return true, nil
}

func (f *fakeJobStore) ListSubscriptions(_ context.Context) ([]store.Subscription, error) {
	if f.err != nil {
		return nil, f.err
	}
	var result []store.Subscription
	for _, sub := range f.subscriptions {
		result = append(result, sub)
	}
	sort.Slice(result, func(i, j int) bool { return result[i].SeriesID < result[j].SeriesID })
	return result, nil
}

func (f *fakeJobStore) SetSubscriptionEnabled(_ context.Context, seriesID string, enabled bool) error {
	if f.err != nil {
		return f.err
	}
	sub, exists := f.subscriptions[seriesID]
	if !exists {
		return store.ErrInvalidTransition
	}
	sub.Enabled = enabled
	f.subscriptions[seriesID] = sub
	return nil
}

func (f *fakeJobStore) DeleteSubscription(_ context.Context, seriesID string) (bool, error) {
	if f.err != nil {
		return false, f.err
	}
	if _, exists := f.subscriptions[seriesID]; !exists {
		return false, nil
	}
	delete(f.subscriptions, seriesID)
	return true, nil
}

func (f *fakeJobStore) ListSucceededJobs(_ context.Context, limit int) ([]store.Job, error) {
	if f.err != nil {
		return nil, f.err
	}
	var result []store.Job
	for _, job := range f.jobs {
		if job.Status == "succeeded" {
			result = append(result, job)
		}
	}
	sort.Slice(result, func(i, j int) bool { return result[i].ID > result[j].ID })
	if len(result) > limit {
		result = result[:limit]
	}
	return result, nil
}

func (f *fakeJobStore) ListLibrarySeries(_ context.Context) ([]store.LibrarySeries, error) {
	if f.err != nil {
		return nil, f.err
	}
	bySeries := make(map[string]*store.LibrarySeries)
	latestIDs := make(map[string]int64)
	for _, job := range f.jobs {
		if job.Status != "succeeded" {
			continue
		}
		item := bySeries[job.SeriesID]
		if item == nil {
			item = &store.LibrarySeries{SeriesID: job.SeriesID}
			bySeries[job.SeriesID] = item
		}
		item.EpisodeCount++
		if job.FileSizeBytes != nil {
			item.TotalSizeBytes += *job.FileSizeBytes
		}
		current := store.Job{ID: latestIDs[job.SeriesID], FinishedAt: item.LatestFinishedAt}
		if item.SeriesTitle == "" || jobFinishedLater(job, current) {
			item.SeriesTitle = job.SeriesTitle
			item.LatestTitle = job.Title
			item.BroadcasterName = job.BroadcasterName
			item.ThumbnailPath = job.ThumbnailPath
			if job.FinishedAt != nil {
				finished := *job.FinishedAt
				item.LatestFinishedAt = &finished
			}
			latestIDs[job.SeriesID] = job.ID
		}
		_, item.Subscribed = f.subscriptions[job.SeriesID]
	}
	result := make([]store.LibrarySeries, 0, len(bySeries))
	for _, item := range bySeries {
		result = append(result, *item)
	}
	sort.Slice(result, func(i, j int) bool {
		left, right := result[i].LatestFinishedAt, result[j].LatestFinishedAt
		if left == nil || right == nil {
			if left != right {
				return left != nil
			}
		} else if !left.Equal(*right) {
			return left.After(*right)
		}
		return result[i].SeriesID < result[j].SeriesID
	})
	return result, nil
}

func (f *fakeJobStore) ListSucceededJobsBySeries(_ context.Context, seriesID string) ([]store.Job, error) {
	if f.err != nil {
		return nil, f.err
	}
	var result []store.Job
	for _, job := range f.jobs {
		if job.Status == "succeeded" && job.SeriesID == seriesID {
			result = append(result, job)
		}
	}
	sortJobsLatest(result)
	return result, nil
}

func (f *fakeJobStore) GetSucceededJob(_ context.Context, id int64) (store.Job, error) {
	if f.err != nil {
		return store.Job{}, f.err
	}
	for _, job := range f.jobs {
		if job.ID == id && job.Status == "succeeded" {
			return job, nil
		}
	}
	return store.Job{}, pgx.ErrNoRows
}

func (f *fakeJobStore) DeleteSucceededJob(_ context.Context, id int64) error {
	if f.beforeDeleteSucceeded != nil {
		f.beforeDeleteSucceeded()
	}
	if f.err != nil {
		return f.err
	}
	for episodeID, job := range f.jobs {
		if job.ID == id && job.Status == "succeeded" {
			delete(f.jobs, episodeID)
			return nil
		}
	}
	return store.ErrInvalidTransition
}