package services

import (
	"testing"
	"time"

	"github.com/stretchr/testify/assert"
	"github.com/stretchr/testify/require"
	"gorm.io/driver/sqlite"
	"gorm.io/gorm"
	"gorm.io/gorm/logger"

	"github.com/treytartt/honeydue-api/internal/config"
	"github.com/treytartt/honeydue-api/internal/models"
	"github.com/treytartt/honeydue-api/internal/repositories"
)

func setupRefreshTestDB(t *testing.T) *gorm.DB {
	t.Helper()
	db, err := gorm.Open(sqlite.Open(":memory:"), &gorm.Config{
		Logger: logger.Default.LogMode(logger.Silent),
	})
	require.NoError(t, err)

	err = db.AutoMigrate(&models.User{}, &models.UserProfile{}, &models.AuthToken{})
	require.NoError(t, err)

	return db
}

func createRefreshTestUser(t *testing.T, db *gorm.DB) *models.User {
	t.Helper()
	user := &models.User{
		Username: "refreshtest",
		Email:    "refresh@test.com",
		IsActive: true,
	}
	require.NoError(t, user.SetPassword("Password123"))
	require.NoError(t, db.Create(user).Error)
	return user
}

func createTokenWithAge(t *testing.T, db *gorm.DB, userID uint, ageDays int) *models.AuthToken {
	t.Helper()
	token := &models.AuthToken{
		UserID: userID,
	}
	require.NoError(t, db.Create(token).Error)

	// Backdate the token's Created timestamp after creation to bypass autoCreateTime
	backdated := time.Now().UTC().AddDate(0, 0, -ageDays)
	require.NoError(t, db.Model(token).Update("created", backdated).Error)
	token.Created = backdated

	return token
}

func newTestAuthService(db *gorm.DB) *AuthService {
	userRepo := repositories.NewUserRepository(db)
	cfg := &config.Config{
		Security: config.SecurityConfig{
			SecretKey:        "test-secret",
			TokenExpiryDays:  90,
			TokenRefreshDays: 60,
		},
	}
	return NewAuthService(userRepo, cfg)
}

func TestRefreshToken_FreshToken_ReturnsExisting(t *testing.T) {
	db := setupRefreshTestDB(t)
	user := createRefreshTestUser(t, db)
	token := createTokenWithAge(t, db, user.ID, 30) // 30 days old, well within fresh window

	svc := newTestAuthService(db)

	resp, err := svc.RefreshToken(token.Key, user.ID)
	require.NoError(t, err)
	assert.Equal(t, token.Key, resp.Token, "fresh token should return the same token")
	assert.Contains(t, resp.Message, "still valid")
}

func TestRefreshToken_InRenewalWindow_ReturnsNewToken(t *testing.T) {
	db := setupRefreshTestDB(t)
	user := createRefreshTestUser(t, db)
	token := createTokenWithAge(t, db, user.ID, 75) // 75 days old, in renewal window (60-90)

	svc := newTestAuthService(db)

	resp, err := svc.RefreshToken(token.Key, user.ID)
	require.NoError(t, err)
	assert.NotEqual(t, token.Key, resp.Token, "should return a new token")
	assert.Contains(t, resp.Message, "refreshed")

	// Verify old token was deleted
	var count int64
	db.Model(&models.AuthToken{}).Where("key = ?", token.Key).Count(&count)
	assert.Equal(t, int64(0), count, "old token should be deleted")

	// Verify new token exists in DB
	db.Model(&models.AuthToken{}).Where("key = ?", resp.Token).Count(&count)
	assert.Equal(t, int64(1), count, "new token should exist in DB")

	// Verify new token belongs to the same user
	var newToken models.AuthToken
	require.NoError(t, db.Where("key = ?", resp.Token).First(&newToken).Error)
	assert.Equal(t, user.ID, newToken.UserID)
}

func TestRefreshToken_ExpiredToken_Returns401(t *testing.T) {
	db := setupRefreshTestDB(t)
	user := createRefreshTestUser(t, db)
	token := createTokenWithAge(t, db, user.ID, 91) // 91 days old, past 90-day expiry

	svc := newTestAuthService(db)

	resp, err := svc.RefreshToken(token.Key, user.ID)
	require.Error(t, err)
	assert.Nil(t, resp)
	assert.Contains(t, err.Error(), "error.token_expired")
}

func TestRefreshToken_AtExactBoundary60Days(t *testing.T) {
	db := setupRefreshTestDB(t)
	user := createRefreshTestUser(t, db)
	// Exactly 60 days: token age == refreshDays, so tokenAge < refreshDuration is false,
	// meaning it enters the renewal window
	token := createTokenWithAge(t, db, user.ID, 61)

	svc := newTestAuthService(db)

	resp, err := svc.RefreshToken(token.Key, user.ID)
	require.NoError(t, err)
	assert.NotEqual(t, token.Key, resp.Token, "token at 61 days should be refreshed")
}

func TestRefreshToken_InvalidToken_Returns401(t *testing.T) {
	db := setupRefreshTestDB(t)
	user := createRefreshTestUser(t, db)

	svc := newTestAuthService(db)

	resp, err := svc.RefreshToken("nonexistent-token-key", user.ID)
	require.Error(t, err)
	assert.Nil(t, resp)
	assert.Contains(t, err.Error(), "error.invalid_token")
}

func TestRefreshToken_WrongUser_Returns401(t *testing.T) {
	db := setupRefreshTestDB(t)
	user := createRefreshTestUser(t, db)
	token := createTokenWithAge(t, db, user.ID, 75)

	svc := newTestAuthService(db)

	// Try to refresh with a different user ID
	resp, err := svc.RefreshToken(token.Key, user.ID+999)
	require.Error(t, err)
	assert.Nil(t, resp)
	assert.Contains(t, err.Error(), "error.invalid_token")
}

func TestRefreshToken_FreshTokenAt59Days_ReturnsExisting(t *testing.T) {
	db := setupRefreshTestDB(t)
	user := createRefreshTestUser(t, db)
	token := createTokenWithAge(t, db, user.ID, 59) // 59 days, just under the 60-day threshold

	svc := newTestAuthService(db)

	resp, err := svc.RefreshToken(token.Key, user.ID)
	require.NoError(t, err)
	assert.Equal(t, token.Key, resp.Token, "token at 59 days should NOT be refreshed")
}