package persistence

import (
	"context"

	"github.com/Masterminds/squirrel"
	"github.com/navidrome/navidrome/model"
	"github.com/navidrome/navidrome/model/request"
	"github.com/navidrome/navidrome/utils/hasher"
	. "github.com/onsi/ginkgo/v2"
	. "github.com/onsi/gomega"
)

var _ = Describe("sqlRepository", func() {
	var r sqlRepository
	BeforeEach(func() {
		r.ctx = request.WithUser(context.Background(), model.User{ID: "user-id"})
		r.tableName = "table"
	})

	Describe("applyOptions", func() {
		var sq squirrel.SelectBuilder
		BeforeEach(func() {
			sq = squirrel.Select("*").From("test")
			r.sortMappings = map[string]string{
				"name": "title",
			}
		})
		It("does not add any clauses when options is empty", func() {
			sq = r.applyOptions(sq, model.QueryOptions{})
			sql, _, _ := sq.ToSql()
			Expect(sql).To(Equal("SELECT * FROM test"))
		})
		It("adds all option clauses", func() {
			sq = r.applyOptions(sq, model.QueryOptions{
				Sort:   "name",
				Order:  "desc",
				Max:    1,
				Offset: 2,
			})
			sql, _, _ := sq.ToSql()
			Expect(sql).To(Equal("SELECT * FROM test ORDER BY title desc LIMIT 1 OFFSET 2"))
		})
	})

	Describe("toSQL", func() {
		It("returns error for invalid SQL", func() {
			sq := squirrel.Select("*").From("test").Where(1)
			_, _, err := r.toSQL(sq)
			Expect(err).To(HaveOccurred())
		})

		It("returns the same query when there are no placeholders", func() {
			sq := squirrel.Select("*").From("test")
			query, params, err := r.toSQL(sq)
			Expect(err).NotTo(HaveOccurred())
			Expect(query).To(Equal("SELECT * FROM test"))
			Expect(params).To(BeEmpty())
		})

		It("replaces one placeholder correctly", func() {
			sq := squirrel.Select("*").From("test").Where(squirrel.Eq{"id": 1})
			query, params, err := r.toSQL(sq)
			Expect(err).NotTo(HaveOccurred())
			Expect(query).To(Equal("SELECT * FROM test WHERE id = {:p0}"))
			Expect(params).To(HaveKeyWithValue("p0", 1))
		})

		It("replaces multiple placeholders correctly", func() {
			sq := squirrel.Select("*").From("test").Where(squirrel.Eq{"id": 1, "name": "test"})
			query, params, err := r.toSQL(sq)
			Expect(err).NotTo(HaveOccurred())
			Expect(query).To(Equal("SELECT * FROM test WHERE id = {:p0} AND name = {:p1}"))
			Expect(params).To(HaveKeyWithValue("p0", 1))
			Expect(params).To(HaveKeyWithValue("p1", "test"))
		})
	})

	Describe("sanitizeSort", func() {
		BeforeEach(func() {
			r.registerModel(&struct {
				Field string `structs:"field"`
			}{}, nil)
			r.sortMappings = map[string]string{
				"sort1": "mappedSort1",
			}
		})

		When("sanitizing sort", func() {
			It("returns empty if the sort key is not found in the model nor in the mappings", func() {
				sort, _ := r.sanitizeSort("unknown", "")
				Expect(sort).To(BeEmpty())
			})

			// Validation only: buildSortOrder resolves the mapping, so mapping here too would hand
			// sortMapping its own output and re-map values whose parts are themselves keys.
			It("accepts a known sort key without resolving it", func() {
				sort, _ := r.sanitizeSort("sort1", "")
				Expect(sort).To(Equal("sort1"))
			})

			It("is case insensitive", func() {
				sort, _ := r.sanitizeSort("Sort1", "")
				Expect(sort).To(Equal("sort1"))
			})

			It("still resolves the mapping by the time the SQL is built", func() {
				Expect(r.buildSortOrder("sort1", "asc")).To(Equal("mappedSort1 asc"))
			})

			// A mapping whose parts are themselves keys (media_file rated_at = "rating, rated_at")
			// must survive the round trip through sanitizeSort and buildSortOrder unduplicated.
			It("does not re-map a value whose parts are also keys", func() {
				r.sortMappings = map[string]string{"rating": "rating", "rated_at": "rating, rated_at"}
				sort, _ := r.sanitizeSort("rated_at", "")
				Expect(r.buildSortOrder(sort, "asc")).To(Equal("rating asc, rated_at asc"))
			})

			It("returns the field if it is a valid field", func() {
				sort, _ := r.sanitizeSort("field", "")
				Expect(sort).To(Equal("field"))
			})

			It("is case insensitive for fields", func() {
				sort, _ := r.sanitizeSort("FIELD", "")
				Expect(sort).To(Equal("field"))
			})
		})
		When("sanitizing order", func() {
			It("returns 'asc' if order is empty", func() {
				_, order := r.sanitizeSort("", "")
				Expect(order).To(Equal(""))
			})

			It("returns 'asc' if order is 'asc'", func() {
				_, order := r.sanitizeSort("", "ASC")
				Expect(order).To(Equal("asc"))
			})

			It("returns 'desc' if order is 'desc'", func() {
				_, order := r.sanitizeSort("", "desc")
				Expect(order).To(Equal("desc"))
			})

			It("returns 'asc' if order is unknown", func() {
				_, order := r.sanitizeSort("", "something")
				Expect(order).To(Equal("asc"))
			})
		})
	})

	Describe("sortMapping", func() {
		BeforeEach(func() {
			r.sortMappings = map[string]string{
				"name":           "order_album_name, order_album_artist_name",
				"recently_added": "album.created_at, album.id",
			}
		})
		It("maps a single key", func() {
			Expect(r.sortMapping("recently_added")).To(Equal("album.created_at, album.id"))
		})
		It("maps every part of a comma list when all of them are known keys", func() {
			Expect(r.sortMapping("recently_added, name")).
				To(Equal("album.created_at, album.id, order_album_name, order_album_artist_name"))
		})
		It("resolves the known parts of a mixed list and leaves the rest as columns", func() {
			Expect(r.sortMapping("recently_added, play_count")).
				To(Equal("album.created_at, album.id, play_count"))
		})
		// Jellyfin's MusicAlbum SortBy=Runtime,SortName arrives as "duration, name"; duration is a
		// plain album column while name is mapped, and the mapping must survive the mix.
		It("keeps a mapping when an earlier part is a plain column", func() {
			Expect(r.sortMapping("duration, name")).
				To(Equal("duration, order_album_name, order_album_artist_name"))
		})
		It("leaves a raw column list with directions untouched", func() {
			Expect(r.sortMapping("starred desc, rating desc")).To(Equal("starred desc, rating desc"))
		})
		It("does not split an expression on a comma inside its parentheses", func() {
			Expect(r.sortMapping("coalesce(name, ''), title")).To(Equal("coalesce(name, ''), title"))
			Expect(r.sortMapping("coalesce(nullif(a,''), b) desc, c")).To(Equal("coalesce(nullif(a,''), b) desc, c"))
		})
		It("keeps a mapping whose value nests commas inside parentheses", func() {
			r.sortMappings["max_year"] = "coalesce(nullif(original_date,''), cast(max_year as text)), release_date"
			Expect(r.sortMapping("max_year, name")).To(Equal(
				"coalesce(nullif(original_date,''), cast(max_year as text)), release_date, " +
					"order_album_name, order_album_artist_name"))
		})
	})

	Describe("buildSortOrder", func() {
		BeforeEach(func() {
			r.sortMappings = map[string]string{}
		})

		Context("single field", func() {
			It("sorts by specified field", func() {
				sql := r.buildSortOrder("name", "desc")
				Expect(sql).To(Equal("name desc"))
			})
			It("defaults to 'asc'", func() {
				sql := r.buildSortOrder("name", "")
				Expect(sql).To(Equal("name asc"))
			})
			It("inverts pre-defined order", func() {
				sql := r.buildSortOrder("name desc", "desc")
				Expect(sql).To(Equal("name asc"))
			})
			It("forces snake case for field names", func() {
				sql := r.buildSortOrder("AlbumArtist", "asc")
				Expect(sql).To(Equal("album_artist asc"))
			})
		})
		Context("multiple fields", func() {
			It("handles multiple fields", func() {
				sql := r.buildSortOrder("name  desc,age asc,  status desc ", "asc")
				Expect(sql).To(Equal("name desc, age asc, status desc"))
			})
			It("inverts multiple fields", func() {
				sql := r.buildSortOrder("name desc, age, status asc", "desc")
				Expect(sql).To(Equal("name asc, age desc, status desc"))
			})
			It("handles spaces in mapped field", func() {
				r.sortMappings = map[string]string{
					"has_lyrics": "(lyrics != '[]'), updated_at",
				}
				sql := r.buildSortOrder("has_lyrics", "desc")
				Expect(sql).To(Equal("(lyrics != '[]') desc, updated_at desc"))
			})

		})
		Context("function fields", func() {
			It("handles functions with multiple params", func() {
				sql := r.buildSortOrder("substr(id, 7)", "asc")
				Expect(sql).To(Equal("substr(id, 7) asc"))
			})
			It("handles functions with multiple params mixed with multiple fields", func() {
				sql := r.buildSortOrder("name desc, substr(id, 7), status asc", "desc")
				Expect(sql).To(Equal("name asc, substr(id, 7) desc, status desc"))
			})
			It("handles nested functions", func() {
				sql := r.buildSortOrder("name desc, coalesce(nullif(release_date, ''), nullif(original_date, '')), status asc", "desc")
				Expect(sql).To(Equal("name asc, coalesce(nullif(release_date, ''), nullif(original_date, '')) desc, status desc"))
			})
		})
	})

	Describe("resetSeededRandom", func() {
		var id string
		BeforeEach(func() {
			id = r.seedKey()
			hasher.SetSeed(id, "")
		})
		It("does not reset seed if sort is not random", func() {
			var options []model.QueryOptions
			r.resetSeededRandom(options)
			Expect(hasher.CurrentSeed(id)).To(BeEmpty())
		})
		It("resets seed if sort is random", func() {
			options := []model.QueryOptions{{Sort: "random"}}
			r.resetSeededRandom(options)
			Expect(hasher.CurrentSeed(id)).NotTo(BeEmpty())
		})
		It("resets seed if sort is random and seed is provided", func() {
			options := []model.QueryOptions{{Sort: "random", Seed: "seed"}}
			r.resetSeededRandom(options)
			Expect(hasher.CurrentSeed(id)).To(Equal("seed"))
		})
		It("keeps seed when paginating", func() {
			options := []model.QueryOptions{{Sort: "random", Seed: "seed", Offset: 0}}
			r.resetSeededRandom(options)
			Expect(hasher.CurrentSeed(id)).To(Equal("seed"))

			options = []model.QueryOptions{{Sort: "random", Offset: 1}}
			r.resetSeededRandom(options)
			Expect(hasher.CurrentSeed(id)).To(Equal("seed"))
		})
	})

	Describe("applyLibraryFilter", func() {
		var sq squirrel.SelectBuilder
		var savedDB = r.db

		BeforeEach(func() {
			sq = squirrel.Select("*").From("test_table")
			// Add library 2 so a user granted only library 1 is a genuine strict subset.
			savedDB = r.db
			r.db = GetDBXBuilder()
			_, err := r.db.NewQuery("INSERT OR IGNORE INTO library (id, name, path) VALUES (2, 'Lib 2', '/lib2')").Execute()
			Expect(err).ToNot(HaveOccurred())
		})

		AfterEach(func() {
			_, err := r.db.NewQuery("DELETE FROM library WHERE id = 2").Execute()
			Expect(err).ToNot(HaveOccurred())
			r.db = savedDB
		})

		Context("Admin User", func() {
			BeforeEach(func() {
				r.ctx = request.WithUser(context.Background(), model.User{ID: "admin", IsAdmin: true})
			})

			It("should not apply library filter for admin users", func() {
				result := r.applyLibraryFilter(sq)
				sql, _, err := result.ToSql()
				Expect(err).ToNot(HaveOccurred())
				Expect(sql).To(Equal("SELECT * FROM test_table"))
			})
		})

		Context("Regular User with a subset of libraries", func() {
			BeforeEach(func() {
				// Strict subset: granted lib 1, DB has libs 1 and 2, so the filter must apply.
				r.ctx = request.WithUser(context.Background(), model.User{
					ID: "user123", IsAdmin: false, Libraries: model.Libraries{{ID: 1}},
				})
			})

			It("should apply library filter for regular users", func() {
				result := r.applyLibraryFilter(sq)
				sql, args, err := result.ToSql()
				Expect(err).ToNot(HaveOccurred())
				Expect(sql).To(ContainSubstring("IN (SELECT ul.library_id FROM user_library ul WHERE ul.user_id = ?)"))
				Expect(args).To(ContainElement("user123"))
			})

			It("should use custom table name when provided", func() {
				result := r.applyLibraryFilter(sq, "custom_table")
				sql, args, err := result.ToSql()
				Expect(err).ToNot(HaveOccurred())
				Expect(sql).To(ContainSubstring("custom_table.library_id IN"))
				Expect(args).To(ContainElement("user123"))
			})
		})

		Context("Regular User with no libraries", func() {
			BeforeEach(func() {
				r.ctx = request.WithUser(context.Background(), model.User{ID: "empty", IsAdmin: false})
			})

			It("should apply the library filter (never skip on empty)", func() {
				result := r.applyLibraryFilter(sq)
				sql, _, err := result.ToSql()
				Expect(err).ToNot(HaveOccurred())
				Expect(sql).To(ContainSubstring("IN (SELECT ul.library_id FROM user_library ul WHERE ul.user_id = ?)"))
			})
		})

		Context("Regular User who can see all libraries", func() {
			BeforeEach(func() {
				// Grant every library that currently exists in the (shared) DB, so the filter
				// would exclude nothing. Querying the real IDs keeps this correct even if other
				// specs left extra libraries behind, which happens under Ginkgo's randomized order.
				var ids []int
				err := r.db.NewQuery("SELECT id FROM library ORDER BY id").Column(&ids)
				Expect(err).ToNot(HaveOccurred())
				libs := make(model.Libraries, 0, len(ids))
				for _, id := range ids {
					libs = append(libs, model.Library{ID: id})
				}
				r.ctx = request.WithUser(context.Background(), model.User{
					ID: "alllibs", IsAdmin: false, Libraries: libs,
				})
			})

			It("should not apply the library filter (subquery would filter nothing)", func() {
				result := r.applyLibraryFilter(sq)
				sql, _, err := result.ToSql()
				Expect(err).ToNot(HaveOccurred())
				Expect(sql).To(Equal("SELECT * FROM test_table"))
			})

			It("should not apply the filter even with a custom table name", func() {
				result := r.applyLibraryFilter(sq, "custom_table")
				sql, _, err := result.ToSql()
				Expect(err).ToNot(HaveOccurred())
				Expect(sql).To(Equal("SELECT * FROM test_table"))
			})
		})

		Context("Headless Process (No User Context)", func() {
			BeforeEach(func() {
				r.ctx = context.Background() // No user context
			})

			It("should not apply library filter for headless processes", func() {
				result := r.applyLibraryFilter(sq)
				sql, _, err := result.ToSql()
				Expect(err).ToNot(HaveOccurred())
				Expect(sql).To(Equal("SELECT * FROM test_table"))
			})

			It("should not apply library filter even with custom table name", func() {
				result := r.applyLibraryFilter(sq, "custom_table")
				sql, _, err := result.ToSql()
				Expect(err).ToNot(HaveOccurred())
				Expect(sql).To(Equal("SELECT * FROM test_table"))
			})
		})
	})
})