package api

import (
	"bytes"
	"context"
	"encoding/json"
	"net/http"
	"net/http/httptest"
	"os"
	"testing"

	"github.com/go-chi/chi/v5"

	"git.fabledsword.com/bvandeusen/minstrel/internal/auth"
	"git.fabledsword.com/bvandeusen/minstrel/internal/coverart"
)

// apiTestAlbumProvider is a minimal AlbumCoverProvider for use in api
// package tests. Does not implement TestableProvider.
type apiTestAlbumProvider struct {
	id      string
	display string
}

func (p *apiTestAlbumProvider) ID() string                                  { return p.id }
func (p *apiTestAlbumProvider) DisplayName() string                         { return p.display }
func (p *apiTestAlbumProvider) RequiresAPIKey() bool                        { return false }
func (p *apiTestAlbumProvider) DefaultEnabled() bool                        { return true }
func (p *apiTestAlbumProvider) Configure(_ coverart.ProviderSettings) error { return nil }
func (p *apiTestAlbumProvider) FetchAlbumCover(_ context.Context, _ coverart.AlbumRef) ([]byte, error) {
	return []byte("img"), nil
}

// apiTestTestableProvider is an AlbumCoverProvider that also implements
// TestableProvider (so the test connection button exercises the success path).
type apiTestTestableProvider struct {
	apiTestAlbumProvider
}

func (p *apiTestTestableProvider) TestConnection(_ context.Context) error { return nil }

func newAdminCoverSourcesRouter(h *handlers) chi.Router {
	r := chi.NewRouter()
	r.Route("/api/admin", func(admin chi.Router) {
		admin.Use(auth.RequireAdmin())
		admin.Get("/cover-sources", h.handleListCoverSources)
		admin.Patch("/cover-sources/{provider_id}", h.handleUpdateCoverSource)
		admin.Post("/cover-sources/{provider_id}/test", h.handleTestCoverSource)
	})
	return r
}

// testHandlersWithCoverSettings extends testHandlers by installing a
// SettingsService backed by the test DB. Caller is responsible for
// registering whichever fake providers the test needs BEFORE calling
// this helper, via coverart.Register. Use coverart.ResetRegistryForTests
// with t.Cleanup to restore registry state after the test.
func testHandlersWithCoverSettings(t *testing.T) (*handlers, *coverart.SettingsService) {
	t.Helper()
	h, pool := testHandlers(t)
	s, err := coverart.NewSettingsService(context.Background(), pool, h.logger)
	if err != nil {
		t.Fatalf("NewSettingsService: %v", err)
	}
	h.coverSettings = s
	return h, s
}

func TestAdminListCoverSources_ReturnsRegisteredProviders(t *testing.T) {
	if os.Getenv("MINSTREL_TEST_DATABASE_URL") == "" {
		t.Skip("MINSTREL_TEST_DATABASE_URL not set")
	}
	coverart.ResetRegistryForTests()
	t.Cleanup(coverart.ResetRegistryForTests)

	coverart.Register(&apiTestAlbumProvider{id: "test-album-prov", display: "Test Album Provider"})

	h, _ := testHandlersWithCoverSettings(t)
	admin := seedUser(t, h.pool, "cslist", "pw", true)

	req := httptest.NewRequest(http.MethodGet, "/api/admin/cover-sources", nil)
	req = withUser(req, admin)
	rec := httptest.NewRecorder()
	newAdminCoverSourcesRouter(h).ServeHTTP(rec, req)

	if rec.Code != http.StatusOK {
		t.Fatalf("status = %d, want 200; body=%s", rec.Code, rec.Body.String())
	}
	var resp coverProvidersListResp
	if err := json.Unmarshal(rec.Body.Bytes(), &resp); err != nil {
		t.Fatalf("decode: %v", err)
	}
	if len(resp.Providers) != 1 {
		t.Fatalf("providers len = %d, want 1", len(resp.Providers))
	}
	p := resp.Providers[0]
	if p.ID != "test-album-prov" {
		t.Errorf("ID = %q, want test-album-prov", p.ID)
	}
	if p.DisplayName != "Test Album Provider" {
		t.Errorf("DisplayName = %q, want Test Album Provider", p.DisplayName)
	}
	if p.APIKeySet {
		t.Error("api_key_set = true, want false (no key set)")
	}
	// apiTestAlbumProvider implements AlbumCoverProvider but not TestableProvider.
	if p.Testable {
		t.Error("testable = true, want false")
	}
	found := false
	for _, s := range p.Supports {
		if s == "album_cover" {
			found = true
		}
	}
	if !found {
		t.Errorf("supports = %v, want to include album_cover", p.Supports)
	}
}

func TestAdminUpdateCoverSource_FlippingEnabledBumpsVersion(t *testing.T) {
	if os.Getenv("MINSTREL_TEST_DATABASE_URL") == "" {
		t.Skip("MINSTREL_TEST_DATABASE_URL not set")
	}
	coverart.ResetRegistryForTests()
	t.Cleanup(coverart.ResetRegistryForTests)

	coverart.Register(&apiTestAlbumProvider{id: "flip-prov", display: "Flip Provider"})

	h, _ := testHandlersWithCoverSettings(t)
	admin := seedUser(t, h.pool, "csflip", "pw", true)

	disabled := false
	body, _ := json.Marshal(updateCoverSourceReq{Enabled: &disabled})
	req := httptest.NewRequest(http.MethodPatch, "/api/admin/cover-sources/flip-prov", bytes.NewReader(body))
	req.Header.Set("Content-Type", "application/json")
	req = withUser(req, admin)
	rec := httptest.NewRecorder()
	newAdminCoverSourcesRouter(h).ServeHTTP(rec, req)

	if rec.Code != http.StatusOK {
		t.Fatalf("status = %d, want 200; body=%s", rec.Code, rec.Body.String())
	}
	var resp updateCoverSourceResp
	if err := json.Unmarshal(rec.Body.Bytes(), &resp); err != nil {
		t.Fatalf("decode: %v", err)
	}
	if !resp.VersionBumped {
		t.Error("version_bumped = false, want true after flipping enabled")
	}
}

func TestAdminUpdateCoverSource_KeyOnlyDoesNotBump(t *testing.T) {
	if os.Getenv("MINSTREL_TEST_DATABASE_URL") == "" {
		t.Skip("MINSTREL_TEST_DATABASE_URL not set")
	}
	coverart.ResetRegistryForTests()
	t.Cleanup(coverart.ResetRegistryForTests)

	coverart.Register(&apiTestAlbumProvider{id: "key-prov", display: "Key Provider"})

	h, _ := testHandlersWithCoverSettings(t)
	admin := seedUser(t, h.pool, "cskey", "pw", true)

	newKey := "newkey"
	body, _ := json.Marshal(updateCoverSourceReq{APIKey: &newKey})
	req := httptest.NewRequest(http.MethodPatch, "/api/admin/cover-sources/key-prov", bytes.NewReader(body))
	req.Header.Set("Content-Type", "application/json")
	req = withUser(req, admin)
	rec := httptest.NewRecorder()
	newAdminCoverSourcesRouter(h).ServeHTTP(rec, req)

	if rec.Code != http.StatusOK {
		t.Fatalf("status = %d, want 200; body=%s", rec.Code, rec.Body.String())
	}
	var resp updateCoverSourceResp
	if err := json.Unmarshal(rec.Body.Bytes(), &resp); err != nil {
		t.Fatalf("decode: %v", err)
	}
	if resp.VersionBumped {
		t.Error("version_bumped = true, want false for key-only change")
	}
	if !resp.APIKeySet {
		t.Error("api_key_set = false, want true after setting key")
	}
}

func TestAdminUpdateCoverSource_UnknownProvider404(t *testing.T) {
	if os.Getenv("MINSTREL_TEST_DATABASE_URL") == "" {
		t.Skip("MINSTREL_TEST_DATABASE_URL not set")
	}
	coverart.ResetRegistryForTests()
	t.Cleanup(coverart.ResetRegistryForTests)

	// No providers registered — anything we patch will be not-found.
	h, _ := testHandlersWithCoverSettings(t)
	admin := seedUser(t, h.pool, "cs404", "pw", true)

	body, _ := json.Marshal(updateCoverSourceReq{})
	req := httptest.NewRequest(http.MethodPatch, "/api/admin/cover-sources/missing", bytes.NewReader(body))
	req.Header.Set("Content-Type", "application/json")
	req = withUser(req, admin)
	rec := httptest.NewRecorder()
	newAdminCoverSourcesRouter(h).ServeHTTP(rec, req)

	if rec.Code != http.StatusNotFound {
		t.Fatalf("status = %d, want 404; body=%s", rec.Code, rec.Body.String())
	}
}

func TestAdminTestCoverSource_NonAdminReturns403(t *testing.T) {
	if os.Getenv("MINSTREL_TEST_DATABASE_URL") == "" {
		t.Skip("MINSTREL_TEST_DATABASE_URL not set")
	}
	coverart.ResetRegistryForTests()
	t.Cleanup(coverart.ResetRegistryForTests)

	coverart.Register(&apiTestTestableProvider{apiTestAlbumProvider{id: "testable-prov", display: "Testable"}})

	h, _ := testHandlersWithCoverSettings(t)
	nonAdmin := seedUser(t, h.pool, "csnoadmin", "pw", false)

	req := httptest.NewRequest(http.MethodPost, "/api/admin/cover-sources/testable-prov/test", nil)
	req = withUser(req, nonAdmin)
	rec := httptest.NewRecorder()
	newAdminCoverSourcesRouter(h).ServeHTTP(rec, req)

	if rec.Code != http.StatusForbidden {
		t.Fatalf("status = %d, want 403; body=%s", rec.Code, rec.Body.String())
	}
}

func TestAdminTestCoverSource_NotTestableReturnsOkFalse(t *testing.T) {
	if os.Getenv("MINSTREL_TEST_DATABASE_URL") == "" {
		t.Skip("MINSTREL_TEST_DATABASE_URL not set")
	}
	coverart.ResetRegistryForTests()
	t.Cleanup(coverart.ResetRegistryForTests)

	// apiTestAlbumProvider does NOT implement TestableProvider.
	coverart.Register(&apiTestAlbumProvider{id: "nontestable-prov", display: "Non-Testable"})

	h, _ := testHandlersWithCoverSettings(t)
	admin := seedUser(t, h.pool, "csntest", "pw", true)

	req := httptest.NewRequest(http.MethodPost, "/api/admin/cover-sources/nontestable-prov/test", nil)
	req = withUser(req, admin)
	rec := httptest.NewRecorder()
	newAdminCoverSourcesRouter(h).ServeHTTP(rec, req)

	if rec.Code != http.StatusOK {
		t.Fatalf("status = %d, want 200; body=%s", rec.Code, rec.Body.String())
	}
	var resp testCoverSourceResp
	if err := json.Unmarshal(rec.Body.Bytes(), &resp); err != nil {
		t.Fatalf("decode: %v", err)
	}
	if resp.OK {
		t.Error("ok = true, want false for non-testable provider")
	}
	if resp.Error == "" {
		t.Error("error string empty, want message mentioning test connection")
	}
}