package e2e

import (
	"net/http"

	"github.com/navidrome/navidrome/model"
	. "github.com/onsi/ginkgo/v2"
	. "github.com/onsi/gomega"
)

var _ = Describe("Similar", func() {
	BeforeEach(func() { setupTestDB() })

	Describe("GET /Artists/{id}/Similar", func() {
		It("returns the provider's similar artists, excluding ones not in the library", func() {
			providerFake.similarArtists = model.Artists{
				{ID: testID("z"), Name: "Led Zeppelin"},
				{ID: "", Name: "Not In Library"}, // no id -> not present -> excluded
			}
			q := queryResult(get("/Artists/" + enc(artistID("The Beatles")) + "/Similar"))
			Expect(names(q.Items)).To(ConsistOf("Led Zeppelin"))
			Expect(q.Items[0].Type).To(Equal("MusicArtist"))
		})

		It("returns an empty result (not 404) when the provider has nothing", func() {
			q := queryResult(get("/Artists/" + enc(artistID("The Beatles")) + "/Similar"))
			Expect(q.Items).To(BeEmpty())
			Expect(q.TotalRecordCount).To(Equal(0))
		})

		// Unlike an unresolvable-but-well-formed id (empty result above), a malformed itemId never
		// reaches provider lookup at all — itemIDParam rejects it first.
		It("404s a malformed itemId", func() {
			w := get("/Artists/not-a-valid-id/Similar")
			Expect(w.Code).To(Equal(http.StatusNotFound))
		})
	})

	Describe("GET /Items/{id}/Similar", func() {
		It("returns similar songs for a track", func() {
			providerFake.similarSongs = model.MediaFiles{{ID: testID("x1"), Title: "Similar Song", LibraryID: 1}}
			q := queryResult(get("/Items/" + enc(songID("So What")) + "/Similar"))
			Expect(names(q.Items)).To(ConsistOf("Similar Song"))
			Expect(q.Items[0].Type).To(Equal("Audio"))
		})

		It("excludes similar songs from libraries the user can't access", func() {
			providerFake.similarSongs = model.MediaFiles{
				{ID: testID("x1"), Title: "In Library", LibraryID: 1},
				{ID: testID("x2"), Title: "Other Library", LibraryID: 2}, // regularUser has no access
			}
			q := queryResult(getAs(regularUser, "/Items/"+enc(songID("So What"))+"/Similar"))
			Expect(names(q.Items)).To(ConsistOf("In Library"))
		})

		It("returns similar albums (derived from similar songs, de-duplicated) for an album", func() {
			providerFake.similarSongs = model.MediaFiles{
				{ID: testID("x1"), AlbumID: albumID("IV")},
				{ID: testID("x2"), AlbumID: albumID("IV")}, // same album -> counted once
				{ID: testID("x3"), AlbumID: albumID("Kind of Blue")},
			}
			q := queryResult(get("/Items/" + enc(albumID("Abbey Road")) + "/Similar"))
			Expect(names(q.Items)).To(Equal([]string{"IV", "Kind of Blue"}))
			Expect(q.Items[0].Type).To(Equal("MusicAlbum"))
		})

		It("excludes similar albums from libraries the user can't access", func() {
			// Seed an album in a second library the regular user has no access to, and point a
			// provider similar-song at it.
			otherLib := model.Library{ID: 2, Name: "Other Library", Path: "fake:///other"}
			Expect(ds.Library().Put(ctx, &otherLib)).To(Succeed())
			otherAlbum := model.Album{ID: testID("other-album"), Name: "Other Album", LibraryID: 2}
			Expect(ds.Album().Put(ctx, &otherAlbum)).To(Succeed())

			providerFake.similarSongs = model.MediaFiles{
				{ID: testID("x1"), AlbumID: albumID("IV")},         // library 1 -> visible
				{ID: testID("x2"), AlbumID: testID("other-album")}, // library 2 -> filtered for regularUser
			}
			q := queryResult(getAs(regularUser, "/Items/"+enc(albumID("Abbey Road"))+"/Similar"))
			Expect(names(q.Items)).To(ConsistOf("IV"))
		})

		It("returns an empty result (not 404) for an unknown item, so the client stops retrying", func() {
			q := queryResult(get("/Items/" + enc(testID("does-not-exist")) + "/Similar"))
			Expect(q.Items).To(BeEmpty())
		})

		It("404s a malformed itemId", func() {
			w := get("/Items/not-a-valid-id/Similar")
			Expect(w.Code).To(Equal(http.StatusNotFound))
		})
	})

	// Finamp plays exactly what InstantMix returns, so a track seed must lead its own mix.
	Describe("GET /Items/{id}/InstantMix", func() {
		It("returns the seed track first, followed by similar songs", func() {
			providerFake.similarSongs = model.MediaFiles{{ID: testID("x1"), Title: "Similar Song", LibraryID: 1}}
			q := queryResult(get("/Items/" + enc(songID("So What")) + "/InstantMix?limit=19"))
			Expect(names(q.Items)).To(Equal([]string{"So What", "Similar Song"}))
			Expect(q.Items[0].Type).To(Equal("Audio"))
		})

		It("does not duplicate the seed when the provider returns it", func() {
			providerFake.similarSongs = model.MediaFiles{
				{ID: songID("So What"), Title: "So What", LibraryID: 1},
				{ID: testID("x1"), Title: "Similar Song", LibraryID: 1},
			}
			q := queryResult(get("/Items/" + enc(songID("So What")) + "/InstantMix"))
			Expect(names(q.Items)).To(Equal([]string{"So What", "Similar Song"}))
		})

		It("caps the mix at the requested limit", func() {
			providerFake.similarSongs = model.MediaFiles{
				{ID: testID("x1"), Title: "S1", LibraryID: 1},
				{ID: testID("x2"), Title: "S2", LibraryID: 1},
				{ID: testID("x3"), Title: "S3", LibraryID: 1},
			}
			q := queryResult(get("/Items/" + enc(songID("So What")) + "/InstantMix?limit=2"))
			Expect(names(q.Items)).To(Equal([]string{"So What", "S1"}))
		})

		It("excludes similar songs from libraries the user can't access", func() {
			providerFake.similarSongs = model.MediaFiles{
				{ID: testID("x1"), Title: "In Library", LibraryID: 1},
				{ID: testID("x2"), Title: "Other Library", LibraryID: 2},
			}
			q := queryResult(getAs(regularUser, "/Items/"+enc(songID("So What"))+"/InstantMix"))
			Expect(names(q.Items)).To(Equal([]string{"So What", "In Library"}))
		})

		It("returns a mix of the provider's similar songs for an artist seed", func() {
			providerFake.similarSongs = model.MediaFiles{{ID: testID("x1"), Title: "Artist Mix Song", LibraryID: 1}}
			q := queryResult(get("/Items/" + enc(artistID("Miles Davis")) + "/InstantMix"))
			Expect(names(q.Items)).To(Equal([]string{"Artist Mix Song"}))
		})

		It("returns an empty result (not 404) for an unknown item", func() {
			w := get("/Items/" + enc(testID("does-not-exist")) + "/InstantMix")
			Expect(w.Code).To(Equal(200))
			Expect(queryResult(w).Items).To(BeEmpty())
		})

		It("returns only the seed when the provider has nothing", func() {
			q := queryResult(get("/Items/" + enc(songID("Help!")) + "/InstantMix"))
			Expect(names(q.Items)).To(Equal([]string{"Help!"}))
		})

		It("404s a malformed itemId", func() {
			w := get("/Items/not-a-valid-id/InstantMix")
			Expect(w.Code).To(Equal(http.StatusNotFound))
		})
	})

	Describe("type-specific InstantMix routes", func() {
		BeforeEach(func() {
			providerFake.similarSongs = model.MediaFiles{{ID: testID("x1"), Title: "Mix Song", LibraryID: 1}}
		})

		It("leads a song mix with the seed on /Songs/{id}/InstantMix", func() {
			q := queryResult(get("/Songs/" + enc(songID("So What")) + "/InstantMix"))
			Expect(names(q.Items)).To(Equal([]string{"So What", "Mix Song"}))
		})

		DescribeTable("returns the provider's mix",
			func(path func() string) {
				q := queryResult(get(path()))
				Expect(names(q.Items)).To(Equal([]string{"Mix Song"}))
			},
			Entry("Albums/{id}", func() string { return "/Albums/" + enc(albumID("Abbey Road")) + "/InstantMix" }),
			Entry("Artists/{id}", func() string { return "/Artists/" + enc(artistID("Miles Davis")) + "/InstantMix" }),
			Entry("Playlists/{id}", func() string {
				return "/Playlists/" + enc(createPlaylist("Seed", []string{enc(songID("So What"))})) + "/InstantMix"
			}),
			Entry("Artists/InstantMix?id=", func() string { return "/Artists/InstantMix?id=" + enc(artistID("Miles Davis")) }),
			Entry("MusicGenres/InstantMix?id=", func() string { return "/MusicGenres/InstantMix?id=" + enc(genreID("Jazz")) }),
		)

		It("404s a malformed id query param", func() {
			Expect(get("/Artists/InstantMix?id=not-a-valid-id").Code).To(Equal(http.StatusNotFound))
		})
	})
})