package api

import (
	"encoding/json"
	"net/http"
	"net/http/httptest"
	"os"
	"path/filepath"
	"testing"

	authmock "geniusrun/backend/internal/auth/mock"
	"geniusrun/backend/internal/garmin"
	"geniusrun/backend/internal/store"
)

// newUnprovisionedServer builds a Server whose "test-user" OIDC subject
// (the identity doJSON's cookie always mints) has no users/profile row yet
// -- every test in this file needs that starting state, unlike
// newTestServer's auto-provisioned default.
func newUnprovisionedServer(t *testing.T) (*Server, *store.DB, *garmin.MockClient) {
	t.Helper()
	db, err := store.Open(filepath.Join(t.TempDir(), "geniusrun_test.db"))
	if err != nil {
		t.Fatalf("store.Open: %v", err)
	}
	t.Cleanup(func() { db.Close() })
	m := &garmin.MockClient{}
	garminFactory := func(garmin.ClientConfig) garmin.Client { return m }
	s := NewServer(db, garminFactory, garmin.ClientConfig{}, garmin.SyncConfig{}, &authmock.Verifier{}, testSessionConfig)
	return s, db, m
}

func TestSetupGarminLogin_AuthenticatesWithoutCreatingAccount(t *testing.T) {
	s, db, _ := newUnprovisionedServer(t)
	router := s.Router()

	rec := doJSON(t, router, http.MethodPost, "/api/setup/garmin/login", map[string]any{
		"garmin_email": "runner@example.com", "garmin_password": "hunter2",
	})
	if rec.Code != http.StatusOK {
		t.Fatalf("status = %d, body = %s", rec.Code, rec.Body.String())
	}
	var resp authResponse
	unmarshalBody(t, rec, &resp)
	if resp.Status != "authenticated" {
		t.Fatalf("status = %q, want authenticated", resp.Status)
	}

	if _, found, err := db.GetUserBySub(newCtx(), "test-user"); err != nil || found {
		t.Fatalf("expected no user created yet, found=%v err=%v", found, err)
	}
}

func TestSetupGarminLogin_MFARequiredThenCompleteMFA(t *testing.T) {
	s, db, m := newUnprovisionedServer(t)
	m.AuthResults = []garmin.AuthResult{{Status: garmin.AuthMFARequired, Message: "MFA required"}}
	router := s.Router()

	rec := doJSON(t, router, http.MethodPost, "/api/setup/garmin/login", map[string]any{
		"garmin_email": "runner@example.com", "garmin_password": "hunter2",
	})
	if rec.Code != http.StatusOK {
		t.Fatalf("login status = %d, body = %s", rec.Code, rec.Body.String())
	}
	var resp authResponse
	unmarshalBody(t, rec, &resp)
	if resp.Status != "mfa_required" {
		t.Fatalf("status = %q, want mfa_required", resp.Status)
	}

	rec = doJSON(t, router, http.MethodPost, "/api/setup/garmin/mfa", map[string]any{"code": "123456"})
	if rec.Code != http.StatusOK {
		t.Fatalf("mfa status = %d, body = %s", rec.Code, rec.Body.String())
	}
	unmarshalBody(t, rec, &resp)
	if resp.Status != "authenticated" {
		t.Fatalf("status after mfa = %q, want authenticated", resp.Status)
	}

	if _, found, err := db.GetUserBySub(newCtx(), "test-user"); err != nil || found {
		t.Fatalf("expected no user created yet even after MFA success, found=%v err=%v", found, err)
	}
}

func TestSetupGarminMFA_RejectsWithoutPriorLoginAttempt(t *testing.T) {
	s, _, _ := newUnprovisionedServer(t)
	rec := doJSON(t, s.Router(), http.MethodPost, "/api/setup/garmin/mfa", map[string]any{"code": "123456"})
	if rec.Code != http.StatusConflict {
		t.Fatalf("status = %d, want 409, body = %s", rec.Code, rec.Body.String())
	}
}

func TestSetupComplete_CreatesAccountWithGarminCredentialsAndClosesEphemeralClient(t *testing.T) {
	db, err := store.Open(filepath.Join(t.TempDir(), "geniusrun_test.db"))
	if err != nil {
		t.Fatalf("store.Open: %v", err)
	}
	t.Cleanup(func() { db.Close() })
	m := &garmin.MockClient{}
	tokenStoreRoot := t.TempDir()
	var factoryConfigs []garmin.ClientConfig
	garminFactory := func(cfg garmin.ClientConfig) garmin.Client {
		factoryConfigs = append(factoryConfigs, cfg)
		return m
	}
	s := NewServer(db, garminFactory, garmin.ClientConfig{TokenStorePath: tokenStoreRoot}, garmin.SyncConfig{}, &authmock.Verifier{}, testSessionConfig)
	router := s.Router()

	rec := doJSON(t, router, http.MethodPost, "/api/setup/garmin/login", map[string]any{
		"garmin_email": "runner@example.com", "garmin_password": "hunter2",
	})
	if rec.Code != http.StatusOK {
		t.Fatalf("login status = %d, body = %s", rec.Code, rec.Body.String())
	}

	rec = doJSON(t, router, http.MethodPost, "/api/setup/complete", map[string]any{"display_name": "Lucie"})
	if rec.Code != http.StatusOK {
		t.Fatalf("complete status = %d, body = %s", rec.Code, rec.Body.String())
	}

	u, found, err := db.GetUserBySub(newCtx(), "test-user")
	if err != nil || !found {
		t.Fatalf("GetUserBySub: found=%v err=%v", found, err)
	}
	profile, err := db.GetProfile(newCtx(), u.ID)
	if err != nil {
		t.Fatalf("GetProfile: %v", err)
	}
	if profile.GarminEmail != "runner@example.com" || profile.GarminPassword != "hunter2" {
		t.Errorf("profile garmin creds = %+v, want email=runner@example.com password=hunter2", profile)
	}
	if profile.GarminConnectedAt == nil {
		t.Error("expected GarminConnectedAt to be set")
	}

	if m.AuthenticateCalls != 1 {
		t.Errorf("AuthenticateCalls = %d, want 1 (only the original login, no redundant re-authentication)", m.AuthenticateCalls)
	}
	if !m.ClosedCalled {
		t.Error("expected the ephemeral client to be Close()d at setup completion, not promoted as-is -- its cfg.TokenStorePath still points at the ephemeral setup/{hash} dir, which would go stale the moment anything (e.g. a Profile save) later respawns it")
	}

	// A later real use must build a genuinely fresh client, configured
	// against the permanent {userID} token store directory -- never the
	// stale ephemeral setup/{hash} one the closed client was carrying.
	if _, err := s.clientFor(newCtx(), u.ID); err != nil {
		t.Fatalf("garminFor: %v", err)
	}
	wantTokenStorePath := filepath.Join(tokenStoreRoot, itoa(u.ID))
	var gotTokenStorePath string
	for _, cfg := range factoryConfigs {
		if cfg.GarminEmail == "runner@example.com" {
			gotTokenStorePath = cfg.TokenStorePath
		}
	}
	if gotTokenStorePath != wantTokenStorePath {
		t.Errorf("garminFor built client with TokenStorePath = %q, want %q", gotTokenStorePath, wantTokenStorePath)
	}
}

func TestSetupComplete_RejectsWithoutSuccessfulGarminConnection(t *testing.T) {
	s, db, _ := newUnprovisionedServer(t)
	rec := doJSON(t, s.Router(), http.MethodPost, "/api/setup/complete", map[string]any{"display_name": "Lucie"})
	if rec.Code != http.StatusConflict {
		t.Fatalf("status = %d, want 409, body = %s", rec.Code, rec.Body.String())
	}
	if _, found, err := db.GetUserBySub(newCtx(), "test-user"); err != nil || found {
		t.Fatalf("expected no user created, found=%v err=%v", found, err)
	}
}

func TestSetupComplete_RejectsEmptyDisplayName(t *testing.T) {
	s, _, _ := newUnprovisionedServer(t)
	router := s.Router()
	rec := doJSON(t, router, http.MethodPost, "/api/setup/garmin/login", map[string]any{
		"garmin_email": "runner@example.com", "garmin_password": "hunter2",
	})
	if rec.Code != http.StatusOK {
		t.Fatalf("login status = %d, body = %s", rec.Code, rec.Body.String())
	}
	rec = doJSON(t, router, http.MethodPost, "/api/setup/complete", map[string]any{"display_name": ""})
	if rec.Code != http.StatusBadRequest {
		t.Fatalf("status = %d, want 400", rec.Code)
	}
}

func TestSetupGarminLogin_RejectsWhenAlreadyProvisioned(t *testing.T) {
	s, _, _ := newTestServer(t) // pre-provisioned "test-user"
	rec := doJSON(t, s.Router(), http.MethodPost, "/api/setup/garmin/login", map[string]any{
		"garmin_email": "runner@example.com", "garmin_password": "hunter2",
	})
	if rec.Code != http.StatusConflict {
		t.Fatalf("status = %d, want 409, body = %s", rec.Code, rec.Body.String())
	}
}

func TestSetupComplete_RejectsWhenAlreadyProvisioned(t *testing.T) {
	s, _, _ := newTestServer(t) // pre-provisioned "test-user"
	rec := doJSON(t, s.Router(), http.MethodPost, "/api/setup/complete", map[string]any{"display_name": "Someone Else"})
	if rec.Code != http.StatusConflict {
		t.Fatalf("status = %d, want 409, body = %s", rec.Code, rec.Body.String())
	}
}

func TestSetupComplete_RenamesTokenStoreDirectory(t *testing.T) {
	db, err := store.Open(filepath.Join(t.TempDir(), "geniusrun_test.db"))
	if err != nil {
		t.Fatalf("store.Open: %v", err)
	}
	t.Cleanup(func() { db.Close() })
	m := &garmin.MockClient{}
	tokenStoreRoot := t.TempDir()
	s := NewServer(db, func(garmin.ClientConfig) garmin.Client { return m }, garmin.ClientConfig{TokenStorePath: tokenStoreRoot}, garmin.SyncConfig{}, &authmock.Verifier{}, testSessionConfig)
	router := s.Router()

	rec := doJSON(t, router, http.MethodPost, "/api/setup/garmin/login", map[string]any{
		"garmin_email": "runner@example.com", "garmin_password": "hunter2",
	})
	if rec.Code != http.StatusOK {
		t.Fatalf("login status = %d, body = %s", rec.Code, rec.Body.String())
	}

	// Simulate what a real subprocess would have written under the
	// ephemeral (subject-keyed) directory during that login call.
	oldDir := setupTokenStoreDir(tokenStoreRoot, "test-user")
	if err := os.MkdirAll(oldDir, 0o755); err != nil {
		t.Fatalf("MkdirAll: %v", err)
	}
	if err := os.WriteFile(filepath.Join(oldDir, "session.json"), []byte("{}"), 0o644); err != nil {
		t.Fatalf("WriteFile: %v", err)
	}

	rec = doJSON(t, router, http.MethodPost, "/api/setup/complete", map[string]any{"display_name": "Lucie"})
	if rec.Code != http.StatusOK {
		t.Fatalf("complete status = %d, body = %s", rec.Code, rec.Body.String())
	}
	u, found, err := db.GetUserBySub(newCtx(), "test-user")
	if err != nil || !found {
		t.Fatalf("GetUserBySub: found=%v err=%v", found, err)
	}

	if _, err := os.Stat(oldDir); !os.IsNotExist(err) {
		t.Fatalf("expected old setup token store dir %q to be gone, stat err = %v", oldDir, err)
	}
	newDir := filepath.Join(tokenStoreRoot, itoa(u.ID))
	if _, err := os.Stat(filepath.Join(newDir, "session.json")); err != nil {
		t.Fatalf("expected renamed token store dir %q to contain session.json: %v", newDir, err)
	}
}

func unmarshalBody(t *testing.T, rec *httptest.ResponseRecorder, v any) {
	t.Helper()
	if err := json.Unmarshal(rec.Body.Bytes(), v); err != nil {
		t.Fatalf("unmarshal response body %q: %v", rec.Body.String(), err)
	}
}

// Regression: os.Rename refuses to replace an existing directory, so a
// stale {userID} token-store dir (left behind when the DB file was
// recreated -- ids restart at 1 -- while the token-store root survived)
// used to make setup completion silently keep the OLD tokens in place.
// The fresh, just-validated session's directory must win.
func TestSetupComplete_ReplacesStaleTokenStoreDir(t *testing.T) {
	db, err := store.Open(filepath.Join(t.TempDir(), "setup_stale_dir_test.db"))
	if err != nil {
		t.Fatalf("store.Open: %v", err)
	}
	t.Cleanup(func() { db.Close() })
	m := &garmin.MockClient{}
	tokenStoreRoot := t.TempDir()
	s := NewServer(db, func(garmin.ClientConfig) garmin.Client { return m }, garmin.ClientConfig{TokenStorePath: tokenStoreRoot}, garmin.SyncConfig{}, &authmock.Verifier{}, testSessionConfig)
	router := s.Router()

	// The ephemeral setup dir the wrapper would have written tokens into.
	setupDir := setupTokenStoreDir(tokenStoreRoot, "test-user")
	if err := os.MkdirAll(setupDir, 0o755); err != nil {
		t.Fatalf("mkdir setup dir: %v", err)
	}
	if err := os.WriteFile(filepath.Join(setupDir, "oauth_token"), []byte("fresh"), 0o600); err != nil {
		t.Fatalf("write fresh token: %v", err)
	}
	// A stale dir already occupying the permanent {userID} path (fresh DB
	// starts ids at 1).
	staleDir := filepath.Join(tokenStoreRoot, "1")
	if err := os.MkdirAll(staleDir, 0o755); err != nil {
		t.Fatalf("mkdir stale dir: %v", err)
	}
	if err := os.WriteFile(filepath.Join(staleDir, "oauth_token"), []byte("stale"), 0o600); err != nil {
		t.Fatalf("write stale token: %v", err)
	}

	rec := doJSON(t, router, http.MethodPost, "/api/setup/garmin/login", map[string]any{
		"garmin_email": "runner@example.com", "garmin_password": "hunter2",
	})
	if rec.Code != http.StatusOK {
		t.Fatalf("login status = %d, body = %s", rec.Code, rec.Body.String())
	}
	rec = doJSON(t, router, http.MethodPost, "/api/setup/complete", map[string]any{"display_name": "Lucie"})
	if rec.Code != http.StatusOK {
		t.Fatalf("complete status = %d, body = %s", rec.Code, rec.Body.String())
	}

	u, found, err := db.GetUserBySub(newCtx(), "test-user")
	if err != nil || !found {
		t.Fatalf("GetUserBySub: found=%v err=%v", found, err)
	}
	token, err := os.ReadFile(filepath.Join(tokenStoreRoot, itoa(u.ID), "oauth_token"))
	if err != nil {
		t.Fatalf("read token after complete: %v", err)
	}
	if string(token) != "fresh" {
		t.Fatalf("token content = %q, want the fresh setup session to replace the stale dir", token)
	}
	if _, err := os.Stat(setupDir); !os.IsNotExist(err) {
		t.Errorf("ephemeral setup dir still present after rename: %v", err)
	}
}