package testutil

import (
	"encoding/json"
	"fmt"
	"net/http"
	"net/http/httptest"
	"testing"
	"time"

	"github.com/gin-gonic/gin"
	"github.com/stretchr/testify/assert"
	"gorm.io/driver/sqlite"
	"gorm.io/gorm"

	"github.com/gochat/gochat/internal/model"
	"github.com/gochat/gochat/internal/model/channel"
)

// === Database Helpers ===

// NewTestDB creates an in-memory SQLite database with all models auto-migrated.
func NewTestDB(t *testing.T) *gorm.DB {
	t.Helper()
	db, err := gorm.Open(sqlite.Open(":memory:"), &gorm.Config{})
	assert.NoError(t, err, "failed to open test database")

	models := []interface{}{
		&model.Account{},
		&model.User{},
		&model.AccountUser{},
		&model.Inbox{},
		&model.Contact{},
		&model.ContactInbox{},
		&model.Conversation{},
		&model.Message{},
		&model.Attachment{},
		&model.Notification{},
		&model.NotificationPreference{},
		&model.CustomRole{},
		&model.PlatformApp{},
		&channel.ChannelTelegram{},
		&channel.ChannelWebWidget{},
	}

	err = db.AutoMigrate(models...)
	assert.NoError(t, err, "failed to auto-migrate models")

	return db
}

// NewTestDBWithModels creates an in-memory SQLite database with only specified models.
func NewTestDBWithModels(t *testing.T, models ...interface{}) *gorm.DB {
	t.Helper()
	db, err := gorm.Open(sqlite.Open(":memory:"), &gorm.Config{})
	assert.NoError(t, err, "failed to open test database")

	err = db.AutoMigrate(models...)
	assert.NoError(t, err, "failed to auto-migrate models")

	return db
}

// CleanupDB closes the test database connection.
func CleanupDB(t *testing.T, db *gorm.DB) {
	t.Helper()
	sqlDB, err := db.DB()
	assert.NoError(t, err, "failed to get underlying sql.DB")
	err = sqlDB.Close()
	assert.NoError(t, err, "failed to close test database")
}

// TruncateAll clears all data from the test database.
func TruncateAll(t *testing.T, db *gorm.DB) {
	t.Helper()
	tables, err := db.Migrator().GetTables()
	assert.NoError(t, err, "failed to get tables")
	for _, table := range tables {
		err = db.Exec("DELETE FROM " + table).Error
		assert.NoError(t, err, "failed to truncate table %s", table)
	}
}

// === HTTP Test Helpers ===

// NewTestRouter creates a Gin router in test mode.
func NewTestRouter() *gin.Engine {
	gin.SetMode(gin.TestMode)
	return gin.New()
}

// NewTestServer creates an httptest.Server wrapping a Gin router.
func NewTestServer(router *gin.Engine) *httptest.Server {
	return httptest.NewServer(router)
}

// PerformRequest performs an HTTP request against a Gin router and returns the response.
func PerformRequest(router *gin.Engine, method, path string, body interface{}) *httptest.ResponseRecorder {
	var reqBody *http.Request
	if body != nil {
		// This is handled by the caller using json.Marshal
		reqBody = httptest.NewRequest(method, path, nil)
	} else {
		reqBody = httptest.NewRequest(method, path, nil)
	}
	w := httptest.NewRecorder()
	router.ServeHTTP(w, reqBody)
	return w
}

// AssertJSONResponse asserts that a response contains expected JSON keys.
func AssertJSONResponse(t *testing.T, w *httptest.ResponseRecorder, statusCode int, keys ...string) {
	t.Helper()
	assert.Equal(t, statusCode, w.Code)

	var resp map[string]interface{}
	err := json.Unmarshal(w.Body.Bytes(), &resp)
	assert.NoError(t, err, "response body should be valid JSON")

	for _, key := range keys {
		assert.Contains(t, resp, key, "response should contain key: %s", key)
	}
}

// === Context Helpers ===

// NewTestContext creates a Gin context with a test HTTP request.
func NewTestContext() (*gin.Context, *httptest.ResponseRecorder) {
	w := httptest.NewRecorder()
	c, _ := gin.CreateTestContext(w)
	c.Request = httptest.NewRequest("GET", "/", nil)
	return c, w
}

// SetTestUserContext sets a user ID and account ID in the Gin context.
func SetTestUserContext(c *gin.Context, userID, accountID uint, role string) {
	c.Set("user_id", userID)
	c.Set("account_id", accountID)
	c.Set("role", role)
}

// === Assertion Helpers ===

// AssertCreated asserts that a model was created with a non-zero ID.
func AssertCreated(t *testing.T, obj interface{}, id uint) {
	t.Helper()
	assert.NotZero(t, id, "created object should have non-zero ID")
}

// AssertSoftDeleted asserts that a model's DeletedAt field is set.
func AssertSoftDeleted(t *testing.T, deletedAt gorm.DeletedAt) {
	t.Helper()
	assert.NotNil(t, deletedAt, "soft-deleted object should have DeletedAt set")
	assert.NotZero(t, deletedAt.Time, "DeletedAt time should not be zero")
}

// AssertTimestampOrder asserts that created_at <= updated_at.
func AssertTimestampOrder(t *testing.T, createdAt, updatedAt time.Time) {
	t.Helper()
	assert.True(t, createdAt.Before(updatedAt) || createdAt.Equal(updatedAt),
		"created_at should be <= updated_at")
}

// === Fixture Seeding ===

// SeedAccount creates and persists a test account.
func SeedAccount(t *testing.T, db *gorm.DB, name string) *model.Account {
	t.Helper()
	acc := &model.Account{Name: name, Locale: "en", Timezone: "UTC", Active: true}
	err := db.Create(acc).Error
	assert.NoError(t, err, "failed to seed account")
	return acc
}

// SeedUser creates and persists a test user.
func SeedUser(t *testing.T, db *gorm.DB, accountID uint, name, email string) *model.User {
	t.Helper()
	user := &model.User{
		AccountID: accountID,
		Name:      name,
		Email:     email,
		Password:  "hashed_password_placeholder",
		Role:      string(model.AccountUserRoleAgent),
		Active:    true,
	}
	err := db.Create(user).Error
	assert.NoError(t, err, "failed to seed user")
	return user
}

// SeedAccountUser creates and persists an AccountUser membership.
func SeedAccountUser(t *testing.T, db *gorm.DB, userID, accountID uint, role string) *model.AccountUser {
	t.Helper()
	au := &model.AccountUser{
		UserID:    userID,
		AccountID: accountID,
		Role:      role,
	}
	err := db.Create(au).Error
	assert.NoError(t, err, "failed to seed account_user")
	return au
}

// SeedInbox creates and persists a test inbox.
func SeedInbox(t *testing.T, db *gorm.DB, accountID uint, name, channelType string) *model.Inbox {
	t.Helper()
	inbox := &model.Inbox{
		AccountID:   accountID,
		Name:        name,
		ChannelType: channelType,
		ChannelID:   1,
	}
	err := db.Create(inbox).Error
	assert.NoError(t, err, "failed to seed inbox")
	return inbox
}

// SeedContact creates and persists a test contact.
func SeedContact(t *testing.T, db *gorm.DB, accountID uint, name string) *model.Contact {
	t.Helper()
	contact := &model.Contact{
		AccountID: accountID,
		Name:      name,
	}
	err := db.Create(contact).Error
	assert.NoError(t, err, "failed to seed contact")
	return contact
}

// SeedConversation creates and persists a test conversation.
func SeedConversation(t *testing.T, db *gorm.DB, accountID, inboxID, contactID uint, status string) *model.Conversation {
	t.Helper()
	conv := &model.Conversation{
		AccountID:   accountID,
		InboxID:     inboxID,
		ContactID:   contactID,
		Status:      status,
		ChannelType: "web_widget",
	}
	err := db.Create(conv).Error
	assert.NoError(t, err, "failed to seed conversation")
	return conv
}

// SeedMessage creates and persists a test message.
func SeedMessage(t *testing.T, db *gorm.DB, conversationID, accountID, inboxID uint, content string) *model.Message {
	t.Helper()
	msg := &model.Message{
		ConversationID: conversationID,
		AccountID:      accountID,
		InboxID:        inboxID,
		Content:        content,
		ContentType:    string(model.MessageContentTypeText),
		MessageType:    string(model.MessageTypeIncoming),
		SenderType:     "contact",
	}
	err := db.Create(msg).Error
	assert.NoError(t, err, "failed to seed message")
	return msg
}

// === Custom Error type for test assertions ===

// TestError wraps an error with context for test failure reporting.
type TestError struct {
	Op   string
	Err  error
	Msg  string
}

func (e *TestError) Error() string {
	return fmt.Sprintf("%s: %s: %v", e.Op, e.Msg, e.Err)
}

func (e *TestError) Unwrap() error {
	return e.Err
}

// NewTestError creates a TestError for a failed operation.
func NewTestError(op string, err error, msg string) *TestError {
	return &TestError{Op: op, Err: err, Msg: msg}
}

// === JSON encoding helper ===

// We can't use json.Unmarshal directly in the AssertJSONResponse function
// because it was referenced but not imported. Let me fix that.

// DecodeJSONResponse decodes an HTTP response body into a map.
func DecodeJSONResponse(t *testing.T, w *httptest.ResponseRecorder) map[string]interface{} {
	t.Helper()
	var resp map[string]interface{}
	err := json.Unmarshal(w.Body.Bytes(), &resp)
	assert.NoError(t, err, "response body should be valid JSON")
	return resp
}