package sync

import (
	"GoNavi-Wails/internal/connection"
	"context"
	"reflect"
	"strings"
	"testing"
)

type fakeMigrationDB struct {
	columns   map[string][]connection.ColumnDefinition
	indexes   map[string][]connection.IndexDefinition
	queryData map[string][]map[string]interface{}
	queryCols map[string][]string
}

func (f *fakeMigrationDB) Connect(config connection.ConnectionConfig) error { return nil }
func (f *fakeMigrationDB) Close() error                                     { return nil }
func (f *fakeMigrationDB) Ping() error                                      { return nil }
func (f *fakeMigrationDB) Query(query string) ([]map[string]interface{}, []string, error) {
	if rows, ok := f.queryData[query]; ok {
		return rows, f.queryCols[query], nil
	}
	return nil, nil, nil
}
func (f *fakeMigrationDB) Exec(query string) (int64, error) { return 0, nil }
func (f *fakeMigrationDB) GetDatabases() ([]string, error)  { return nil, nil }
func (f *fakeMigrationDB) GetTables(dbName string) ([]string, error) {
	return nil, nil
}
func (f *fakeMigrationDB) GetCreateStatement(dbName, tableName string) (string, error) {
	return "", nil
}
func (f *fakeMigrationDB) GetColumns(dbName, tableName string) ([]connection.ColumnDefinition, error) {
	key := dbName + "." + tableName
	if rows, ok := f.columns[key]; ok {
		return rows, nil
	}
	return []connection.ColumnDefinition{}, nil
}
func (f *fakeMigrationDB) GetAllColumns(dbName string) ([]connection.ColumnDefinitionWithTable, error) {
	return nil, nil
}
func (f *fakeMigrationDB) GetIndexes(dbName, tableName string) ([]connection.IndexDefinition, error) {
	key := dbName + "." + tableName
	if rows, ok := f.indexes[key]; ok {
		return rows, nil
	}
	return nil, nil
}
func (f *fakeMigrationDB) GetForeignKeys(dbName, tableName string) ([]connection.ForeignKeyDefinition, error) {
	return nil, nil
}
func (f *fakeMigrationDB) GetTriggers(dbName, tableName string) ([]connection.TriggerDefinition, error) {
	return nil, nil
}
func (f *fakeMigrationDB) QueryContext(ctx context.Context, query string) ([]map[string]interface{}, []string, error) {
	return f.Query(query)
}
func (f *fakeMigrationDB) ExecContext(ctx context.Context, query string) (int64, error) {
	return 0, nil
}

func TestBuildMySQLToKingbaseColumnDefinition_AutoIncrementAndBoolean(t *testing.T) {
	t.Parallel()

	def, warnings := buildMySQLToKingbaseColumnDefinition(connection.ColumnDefinition{
		Name:     "id",
		Type:     "int unsigned",
		Nullable: "NO",
		Extra:    "auto_increment",
	})
	if !strings.Contains(def, "bigint") || !strings.Contains(def, "GENERATED BY DEFAULT AS IDENTITY") || !strings.Contains(def, "NOT NULL") {
		t.Fatalf("unexpected definition: %s", def)
	}
	if len(warnings) != 0 {
		t.Fatalf("unexpected warnings: %v", warnings)
	}

	def, warnings = buildMySQLToKingbaseColumnDefinition(connection.ColumnDefinition{
		Name:     "enabled",
		Type:     "tinyint(1)",
		Nullable: "YES",
		Default:  stringPtr("1"),
	})
	if !strings.Contains(def, "boolean") || !strings.Contains(def, "DEFAULT TRUE") {
		t.Fatalf("unexpected boolean definition: %s", def)
	}
	if len(warnings) != 0 {
		t.Fatalf("unexpected warnings for boolean: %v", warnings)
	}
}

func TestBuildMySQLToKingbaseCreateTablePlan_GeneratesAndSkipsIndexes(t *testing.T) {
	t.Parallel()

	sourceDB := &fakeMigrationDB{
		indexes: map[string][]connection.IndexDefinition{
			"shop.orders": {
				{Name: "PRIMARY", ColumnName: "id", NonUnique: 0, SeqInIndex: 1, IndexType: "BTREE"},
				{Name: "idx_user_status", ColumnName: "user_id", NonUnique: 1, SeqInIndex: 1, IndexType: "BTREE"},
				{Name: "idx_user_status", ColumnName: "status", NonUnique: 1, SeqInIndex: 2, IndexType: "BTREE"},
				{Name: "idx_name_prefix", ColumnName: "name", NonUnique: 1, SeqInIndex: 1, IndexType: "BTREE", SubPart: 12},
				{Name: "idx_fulltext_note", ColumnName: "note", NonUnique: 1, SeqInIndex: 1, IndexType: "FULLTEXT"},
			},
		},
	}
	cols := []connection.ColumnDefinition{
		{Name: "id", Type: "bigint", Nullable: "NO", Key: "PRI", Extra: "auto_increment"},
		{Name: "user_id", Type: "bigint", Nullable: "NO"},
		{Name: "status", Type: "varchar(32)", Nullable: "YES"},
		{Name: "name", Type: "varchar(128)", Nullable: "YES"},
		{Name: "note", Type: "text", Nullable: "YES"},
	}
	cfg := SyncConfig{CreateIndexes: true}
	createSQL, postSQL, warnings, unsupported, idxCreate, idxSkip, err := buildMySQLToKingbaseCreateTablePlan(cfg, "public.orders", cols, sourceDB, "shop", "orders")
	if err != nil {
		t.Fatalf("buildMySQLToKingbaseCreateTablePlan returned error: %v", err)
	}
	if !strings.Contains(createSQL, `CREATE TABLE "public"."orders"`) {
		t.Fatalf("unexpected create SQL: %s", createSQL)
	}
	if !strings.Contains(createSQL, `PRIMARY KEY ("id")`) {
		t.Fatalf("create SQL missing primary key: %s", createSQL)
	}
	if idxCreate != 1 || idxSkip != 2 {
		t.Fatalf("unexpected index summary: create=%d skip=%d", idxCreate, idxSkip)
	}
	if len(postSQL) != 1 || !strings.Contains(postSQL[0], `CREATE INDEX "idx_user_status"`) {
		t.Fatalf("unexpected post SQL: %v", postSQL)
	}
	if len(warnings) != 0 {
		t.Fatalf("unexpected warnings: %v", warnings)
	}
	wantUnsupported := []string{
		"索引 idx_name_prefix 使用前缀长度，当前暂不支持迁移",
		"索引 idx_fulltext_note 类型=FULLTEXT，当前暂不支持自动迁移",
	}
	if !reflect.DeepEqual(unsupported, wantUnsupported) {
		t.Fatalf("unexpected unsupported objects: got=%v want=%v", unsupported, wantUnsupported)
	}
}

func TestBuildSchemaMigrationPlan_AutoCreateWhenTargetMissing(t *testing.T) {
	t.Parallel()

	sourceDB := &fakeMigrationDB{
		columns: map[string][]connection.ColumnDefinition{
			"shop.orders": {
				{Name: "id", Type: "bigint", Nullable: "NO", Key: "PRI", Extra: "auto_increment"},
				{Name: "name", Type: "varchar(128)", Nullable: "YES"},
			},
		},
		indexes: map[string][]connection.IndexDefinition{},
	}
	targetDB := &fakeMigrationDB{columns: map[string][]connection.ColumnDefinition{}}
	cfg := SyncConfig{
		SourceConfig:        connection.ConnectionConfig{Type: "mysql", Database: "shop"},
		TargetConfig:        connection.ConnectionConfig{Type: "kingbase", Database: "demo"},
		TargetTableStrategy: "smart",
		CreateIndexes:       true,
	}
	plan, sourceCols, targetCols, err := buildSchemaMigrationPlan(cfg, "orders", sourceDB, targetDB)
	if err != nil {
		t.Fatalf("buildSchemaMigrationPlan returned error: %v", err)
	}
	if len(sourceCols) != 2 || len(targetCols) != 0 {
		t.Fatalf("unexpected columns lengths: source=%d target=%d", len(sourceCols), len(targetCols))
	}
	if plan.TargetTableExists {
		t.Fatalf("expected target table missing")
	}
	if !plan.AutoCreate {
		t.Fatalf("expected auto create enabled")
	}
	if !strings.Contains(plan.PlannedAction, "自动建表") {
		t.Fatalf("unexpected planned action: %s", plan.PlannedAction)
	}
	if !strings.Contains(plan.CreateTableSQL, `CREATE TABLE "public"."orders"`) {
		t.Fatalf("unexpected create table SQL: %s", plan.CreateTableSQL)
	}
}

func stringPtr(v string) *string { return &v }

func TestBuildPGLikeToMySQLCreateTablePlan_GeneratesMySQLDDL(t *testing.T) {
	t.Parallel()

	sourceDB := &fakeMigrationDB{
		indexes: map[string][]connection.IndexDefinition{
			"public.users": {
				{Name: "users_email_key", ColumnName: "email", NonUnique: 0, SeqInIndex: 1, IndexType: "BTREE"},
				{Name: "idx_users_name", ColumnName: "name", NonUnique: 1, SeqInIndex: 1, IndexType: "BTREE"},
			},
		},
	}
	cols := []connection.ColumnDefinition{
		{Name: "id", Type: "integer", Nullable: "NO", Key: "PRI", Extra: "auto_increment"},
		{Name: "email", Type: "character varying(120)", Nullable: "NO"},
		{Name: "name", Type: "text", Nullable: "YES"},
		{Name: "profile", Type: "jsonb", Nullable: "YES"},
	}
	cfg := SyncConfig{CreateIndexes: true}
	createSQL, postSQL, warnings, unsupported, idxCreate, idxSkip, err := buildPGLikeToMySQLCreateTablePlan(cfg, "app.users", cols, sourceDB, "public", "users")
	if err != nil {
		t.Fatalf("buildPGLikeToMySQLCreateTablePlan returned error: %v", err)
	}
	if !strings.Contains(createSQL, "CREATE TABLE `app`.`users`") {
		t.Fatalf("unexpected create SQL: %s", createSQL)
	}
	if !strings.Contains(createSQL, "`id` int AUTO_INCREMENT NOT NULL") {
		t.Fatalf("unexpected id definition: %s", createSQL)
	}
	if !strings.Contains(createSQL, "`profile` json") {
		t.Fatalf("unexpected json definition: %s", createSQL)
	}
	if idxCreate != 2 || idxSkip != 0 {
		t.Fatalf("unexpected index summary: create=%d skip=%d", idxCreate, idxSkip)
	}
	if len(postSQL) != 2 {
		t.Fatalf("unexpected post sql length: %v", postSQL)
	}
	if len(warnings) != 0 {
		t.Fatalf("unexpected warnings: %v", warnings)
	}
	if len(unsupported) != 0 {
		t.Fatalf("unexpected unsupported: %v", unsupported)
	}
}

func TestBuildPGLikeToMySQLPlan_AutoCreateWhenTargetMissing(t *testing.T) {
	t.Parallel()

	sourceDB := &fakeMigrationDB{
		columns: map[string][]connection.ColumnDefinition{
			"public.orders": {
				{Name: "id", Type: "bigint", Nullable: "NO", Key: "PRI", Extra: "auto_increment"},
				{Name: "amount", Type: "numeric(10,2)", Nullable: "NO"},
			},
		},
		indexes: map[string][]connection.IndexDefinition{},
	}
	targetDB := &fakeMigrationDB{columns: map[string][]connection.ColumnDefinition{}}
	cfg := SyncConfig{
		SourceConfig:        connection.ConnectionConfig{Type: "kingbase", Database: "public"},
		TargetConfig:        connection.ConnectionConfig{Type: "mysql", Database: "app"},
		TargetTableStrategy: "smart",
		CreateIndexes:       true,
	}
	plan, sourceCols, targetCols, err := buildPGLikeToMySQLPlan(cfg, "orders", sourceDB, targetDB)
	if err != nil {
		t.Fatalf("buildPGLikeToMySQLPlan returned error: %v", err)
	}
	if len(sourceCols) != 2 || len(targetCols) != 0 {
		t.Fatalf("unexpected columns lengths: source=%d target=%d", len(sourceCols), len(targetCols))
	}
	if plan.TargetTableExists {
		t.Fatalf("expected target table missing")
	}
	if !plan.AutoCreate {
		t.Fatalf("expected auto create enabled")
	}
	if !strings.Contains(plan.CreateTableSQL, "CREATE TABLE `app`.`orders`") {
		t.Fatalf("unexpected create table SQL: %s", plan.CreateTableSQL)
	}
}

func TestBuildMySQLToPGLikeCreateTablePlan_GeneratesPostgresDDL(t *testing.T) {
	t.Parallel()

	sourceDB := &fakeMigrationDB{
		indexes: map[string][]connection.IndexDefinition{
			"shop.orders": {
				{Name: "idx_orders_user", ColumnName: "user_id", NonUnique: 1, SeqInIndex: 1, IndexType: "BTREE"},
				{Name: "idx_orders_user", ColumnName: "status", NonUnique: 1, SeqInIndex: 2, IndexType: "BTREE"},
			},
		},
	}
	cols := []connection.ColumnDefinition{
		{Name: "id", Type: "bigint", Nullable: "NO", Key: "PRI", Extra: "auto_increment"},
		{Name: "user_id", Type: "bigint", Nullable: "NO"},
		{Name: "status", Type: "varchar(32)", Nullable: "YES"},
		{Name: "payload", Type: "json", Nullable: "YES"},
	}
	cfg := SyncConfig{CreateIndexes: true}
	createSQL, postSQL, warnings, unsupported, idxCreate, idxSkip, err := buildMySQLToPGLikeCreateTablePlan("postgres", cfg, "public.orders", cols, sourceDB, "shop", "orders")
	if err != nil {
		t.Fatalf("buildMySQLToPGLikeCreateTablePlan returned error: %v", err)
	}
	if !strings.Contains(createSQL, `CREATE TABLE "public"."orders"`) {
		t.Fatalf("unexpected create SQL: %s", createSQL)
	}
	if !strings.Contains(createSQL, `GENERATED BY DEFAULT AS IDENTITY`) {
		t.Fatalf("missing identity mapping: %s", createSQL)
	}
	if !strings.Contains(createSQL, `jsonb`) {
		t.Fatalf("missing jsonb mapping: %s", createSQL)
	}
	if idxCreate != 1 || idxSkip != 0 {
		t.Fatalf("unexpected index summary: create=%d skip=%d", idxCreate, idxSkip)
	}
	if len(postSQL) != 1 || !strings.Contains(postSQL[0], `CREATE INDEX "idx_orders_user"`) {
		t.Fatalf("unexpected post SQL: %v", postSQL)
	}
	if len(warnings) != 0 || len(unsupported) != 0 {
		t.Fatalf("unexpected warnings/unsupported: warnings=%v unsupported=%v", warnings, unsupported)
	}
}

func TestBuildMySQLToClickHouseCreateTableSQL_GeneratesMergeTree(t *testing.T) {
	t.Parallel()

	cols := []connection.ColumnDefinition{
		{Name: "id", Type: "bigint unsigned", Nullable: "NO", Key: "PRI"},
		{Name: "name", Type: "varchar(128)", Nullable: "YES"},
		{Name: "payload", Type: "json", Nullable: "YES"},
	}
	createSQL, warnings, unsupported := buildMySQLToClickHouseCreateTableSQL("analytics.orders", cols)
	if !strings.Contains(createSQL, "ENGINE = MergeTree()") {
		t.Fatalf("unexpected create SQL: %s", createSQL)
	}
	if !strings.Contains(createSQL, "ORDER BY (`id`)") {
		t.Fatalf("unexpected order by: %s", createSQL)
	}
	if !strings.Contains(createSQL, "`payload` Nullable(String)") {
		t.Fatalf("unexpected json mapping: %s", createSQL)
	}
	if len(warnings) == 0 {
		t.Fatalf("expected warnings for clickhouse semantics")
	}
	if len(unsupported) != 0 {
		t.Fatalf("unexpected unsupported: %v", unsupported)
	}
}

func TestBuildClickHouseToMySQLCreateTableSQL_GeneratesMySQLDDL(t *testing.T) {
	t.Parallel()

	cols := []connection.ColumnDefinition{
		{Name: "id", Type: "UInt64", Nullable: "NO", Key: "PRI"},
		{Name: "event_time", Type: "DateTime", Nullable: "NO"},
		{Name: "payload", Type: "Map(String, String)", Nullable: "YES"},
	}
	createSQL, warnings := buildClickHouseToMySQLCreateTableSQL("app.metrics", cols)
	if !strings.Contains(createSQL, "CREATE TABLE `app`.`metrics`") {
		t.Fatalf("unexpected create SQL: %s", createSQL)
	}
	if !strings.Contains(createSQL, "`id` bigint unsigned NOT NULL") {
		t.Fatalf("unexpected uint64 mapping: %s", createSQL)
	}
	if !strings.Contains(createSQL, "`payload` json") {
		t.Fatalf("unexpected complex type mapping: %s", createSQL)
	}
	if len(warnings) == 0 {
		t.Fatalf("expected warning for limited clickhouse reverse semantics")
	}
}

func TestBuildMySQLToMongoPlan_AutoCreateCollection(t *testing.T) {
	t.Parallel()

	sourceDB := &fakeMigrationDB{
		columns: map[string][]connection.ColumnDefinition{
			"shop.users": {
				{Name: "id", Type: "bigint", Nullable: "NO", Key: "PRI"},
				{Name: "name", Type: "varchar(64)", Nullable: "YES"},
			},
		},
		indexes: map[string][]connection.IndexDefinition{
			"shop.users": {
				{Name: "idx_users_name", ColumnName: "name", NonUnique: 1, SeqInIndex: 1, IndexType: "BTREE"},
			},
		},
	}
	targetDB := &fakeMigrationDB{}
	cfg := SyncConfig{
		SourceConfig:        connection.ConnectionConfig{Type: "mysql", Database: "shop"},
		TargetConfig:        connection.ConnectionConfig{Type: "mongodb", Database: "app"},
		TargetTableStrategy: "smart",
		CreateIndexes:       true,
	}
	plan, sourceCols, targetCols, err := buildMySQLToMongoPlan(cfg, "users", sourceDB, targetDB)
	if err != nil {
		t.Fatalf("buildMySQLToMongoPlan returned error: %v", err)
	}
	if len(sourceCols) != 2 || targetCols != nil {
		t.Fatalf("unexpected source/target columns: %d / %v", len(sourceCols), targetCols)
	}
	if !plan.AutoCreate || len(plan.PreDataSQL) == 0 {
		t.Fatalf("expected auto create collection command: %+v", plan)
	}
	if !strings.Contains(plan.PreDataSQL[0], `"create":"users"`) {
		t.Fatalf("unexpected create collection command: %v", plan.PreDataSQL)
	}
	if len(plan.PostDataSQL) != 1 || !strings.Contains(plan.PostDataSQL[0], `"createIndexes":"users"`) {
		t.Fatalf("unexpected index commands: %v", plan.PostDataSQL)
	}
}

func TestBuildPGLikeToMongoPlan_AutoCreateCollection(t *testing.T) {
	t.Parallel()

	sourceDB := &fakeMigrationDB{
		columns: map[string][]connection.ColumnDefinition{
			"public.orders": {
				{Name: "id", Type: "bigint", Nullable: "NO", Key: "PRI"},
				{Name: "name", Type: "varchar(64)", Nullable: "YES"},
			},
		},
		indexes: map[string][]connection.IndexDefinition{
			"public.orders": {
				{Name: "idx_orders_name", ColumnName: "name", NonUnique: 1, SeqInIndex: 1, IndexType: "BTREE"},
			},
		},
	}
	targetDB := &fakeMigrationDB{}
	cfg := SyncConfig{
		SourceConfig:        connection.ConnectionConfig{Type: "postgres", Database: "public"},
		TargetConfig:        connection.ConnectionConfig{Type: "mongodb", Database: "app"},
		TargetTableStrategy: "smart",
		CreateIndexes:       true,
	}
	plan, sourceCols, targetCols, err := buildPGLikeToMongoPlan(cfg, "orders", sourceDB, targetDB)
	if err != nil {
		t.Fatalf("buildPGLikeToMongoPlan returned error: %v", err)
	}
	if len(sourceCols) != 2 || targetCols != nil {
		t.Fatalf("unexpected source/target columns: %d / %v", len(sourceCols), targetCols)
	}
	if !plan.AutoCreate || len(plan.PreDataSQL) == 0 {
		t.Fatalf("expected auto create collection command: %+v", plan)
	}
	if !strings.Contains(plan.PreDataSQL[0], `"create":"orders"`) {
		t.Fatalf("unexpected create collection command: %v", plan.PreDataSQL)
	}
	if len(plan.PostDataSQL) != 1 || !strings.Contains(plan.PostDataSQL[0], `"createIndexes":"orders"`) {
		t.Fatalf("unexpected index commands: %v", plan.PostDataSQL)
	}
}

func TestBuildClickHouseToMongoPlan_AutoCreateCollection(t *testing.T) {
	t.Parallel()

	sourceDB := &fakeMigrationDB{
		columns: map[string][]connection.ColumnDefinition{
			"analytics.metrics": {
				{Name: "id", Type: "UInt64", Nullable: "NO", Key: "PRI"},
				{Name: "host", Type: "String", Nullable: "YES"},
			},
		},
	}
	targetDB := &fakeMigrationDB{}
	cfg := SyncConfig{
		SourceConfig:        connection.ConnectionConfig{Type: "clickhouse", Database: "analytics"},
		TargetConfig:        connection.ConnectionConfig{Type: "mongodb", Database: "app"},
		TargetTableStrategy: "smart",
	}
	plan, sourceCols, targetCols, err := buildClickHouseToMongoPlan(cfg, "metrics", sourceDB, targetDB)
	if err != nil {
		t.Fatalf("buildClickHouseToMongoPlan returned error: %v", err)
	}
	if len(sourceCols) != 2 || targetCols != nil {
		t.Fatalf("unexpected source/target columns: %d / %v", len(sourceCols), targetCols)
	}
	if !plan.AutoCreate || len(plan.PreDataSQL) == 0 {
		t.Fatalf("expected auto create collection command: %+v", plan)
	}
	if !strings.Contains(plan.PreDataSQL[0], `"create":"metrics"`) {
		t.Fatalf("unexpected create collection command: %v", plan.PreDataSQL)
	}
}

func TestBuildTDengineToMongoPlan_AutoCreateCollection(t *testing.T) {
	t.Parallel()

	sourceDB := &fakeMigrationDB{
		columns: map[string][]connection.ColumnDefinition{
			"src.cpu": {
				{Name: "ts", Type: "TIMESTAMP", Nullable: "NO"},
				{Name: "host", Type: "NCHAR(64)", Nullable: "YES"},
			},
		},
	}
	targetDB := &fakeMigrationDB{}
	cfg := SyncConfig{
		SourceConfig:        connection.ConnectionConfig{Type: "tdengine", Database: "src"},
		TargetConfig:        connection.ConnectionConfig{Type: "mongodb", Database: "app"},
		TargetTableStrategy: "smart",
	}
	plan, sourceCols, targetCols, err := buildTDengineToMongoPlan(cfg, "cpu", sourceDB, targetDB)
	if err != nil {
		t.Fatalf("buildTDengineToMongoPlan returned error: %v", err)
	}
	if len(sourceCols) != 2 || targetCols != nil {
		t.Fatalf("unexpected source/target columns: %d / %v", len(sourceCols), targetCols)
	}
	if !plan.AutoCreate || len(plan.PreDataSQL) == 0 {
		t.Fatalf("expected auto create collection command: %+v", plan)
	}
	if !strings.Contains(plan.PreDataSQL[0], `"create":"cpu"`) {
		t.Fatalf("unexpected create collection command: %v", plan.PreDataSQL)
	}
}

func TestBuildMongoToMySQLPlan_InfersColumnsAndCreatesTable(t *testing.T) {
	t.Parallel()

	query := `{"find":"users","filter":{},"limit":200}`
	sourceDB := &fakeMigrationDB{
		queryData: map[string][]map[string]interface{}{
			query: {
				{"_id": "a1", "name": "alice", "age": int64(18), "profile": map[string]interface{}{"city": "shanghai"}},
				{"_id": "b2", "name": "bob", "profile": map[string]interface{}{"city": "beijing"}},
			},
		},
		queryCols: map[string][]string{query: {"_id", "name", "age", "profile"}},
		indexes: map[string][]connection.IndexDefinition{
			"crm.users": {{Name: "email_1", ColumnName: "name", NonUnique: 1, SeqInIndex: 1, IndexType: "BTREE"}},
		},
	}
	targetDB := &fakeMigrationDB{}
	cfg := SyncConfig{
		SourceConfig:        connection.ConnectionConfig{Type: "mongodb", Database: "crm"},
		TargetConfig:        connection.ConnectionConfig{Type: "mysql", Database: "app"},
		TargetTableStrategy: "smart",
		CreateIndexes:       true,
	}
	plan, sourceCols, _, err := buildMongoToMySQLPlan(cfg, "users", sourceDB, targetDB)
	if err != nil {
		t.Fatalf("buildMongoToMySQLPlan returned error: %v", err)
	}
	if len(sourceCols) == 0 {
		t.Fatalf("expected inferred source cols")
	}
	if !plan.AutoCreate || !strings.Contains(plan.CreateTableSQL, "CREATE TABLE `app`.`users`") {
		t.Fatalf("unexpected create table sql: %s", plan.CreateTableSQL)
	}
	if !strings.Contains(plan.CreateTableSQL, "`_id` text NOT NULL") && !strings.Contains(plan.CreateTableSQL, "`_id` varchar") {
		t.Fatalf("missing inferred _id column: %s", plan.CreateTableSQL)
	}
	if !strings.Contains(plan.CreateTableSQL, "`profile` json") {
		t.Fatalf("expected nested field degrade to json: %s", plan.CreateTableSQL)
	}
	if len(plan.PostDataSQL) != 1 {
		t.Fatalf("expected one post index sql, got=%v", plan.PostDataSQL)
	}
}

func TestBuildTDengineToMySQLPlan_AutoCreateWhenTargetMissing(t *testing.T) {
	t.Parallel()

	sourceDB := &fakeMigrationDB{
		columns: map[string][]connection.ColumnDefinition{
			"metrics.cpu": {
				{Name: "ts", Type: "TIMESTAMP", Nullable: "NO"},
				{Name: "host", Type: "NCHAR(64)", Nullable: "YES", Key: "TAG", Extra: "TAG"},
				{Name: "usage", Type: "DOUBLE", Nullable: "YES"},
			},
		},
	}
	targetDB := &fakeMigrationDB{}
	cfg := SyncConfig{
		SourceConfig:        connection.ConnectionConfig{Type: "tdengine", Database: "metrics"},
		TargetConfig:        connection.ConnectionConfig{Type: "mysql", Database: "app"},
		TargetTableStrategy: "smart",
	}
	plan, sourceCols, targetCols, err := buildTDengineToMySQLPlan(cfg, "cpu", sourceDB, targetDB)
	if err != nil {
		t.Fatalf("buildTDengineToMySQLPlan returned error: %v", err)
	}
	if len(sourceCols) != 3 || len(targetCols) != 0 {
		t.Fatalf("unexpected columns lengths: source=%d target=%d", len(sourceCols), len(targetCols))
	}
	if !plan.AutoCreate {
		t.Fatalf("expected auto create enabled")
	}
	if !strings.Contains(plan.CreateTableSQL, "CREATE TABLE `app`.`cpu`") {
		t.Fatalf("unexpected create table sql: %s", plan.CreateTableSQL)
	}
	if !strings.Contains(plan.CreateTableSQL, "`ts` datetime") {
		t.Fatalf("expected timestamp mapping, got: %s", plan.CreateTableSQL)
	}
	if !strings.Contains(plan.CreateTableSQL, "`host` varchar(64)") {
		t.Fatalf("expected nchar mapping, got: %s", plan.CreateTableSQL)
	}
	if len(plan.Warnings) == 0 || !strings.Contains(strings.Join(plan.Warnings, " "), "TAG") {
		t.Fatalf("expected TAG warning, got: %v", plan.Warnings)
	}
}

func TestBuildTDengineToPGLikePlan_AutoCreateWhenTargetMissing(t *testing.T) {
	t.Parallel()

	sourceDB := &fakeMigrationDB{
		columns: map[string][]connection.ColumnDefinition{
			"metrics.cpu": {
				{Name: "ts", Type: "TIMESTAMP", Nullable: "NO"},
				{Name: "payload", Type: "JSON", Nullable: "YES"},
				{Name: "host", Type: "BINARY(32)", Nullable: "YES", Key: "TAG", Extra: "TAG"},
			},
		},
	}
	targetDB := &fakeMigrationDB{}
	cfg := SyncConfig{
		SourceConfig:        connection.ConnectionConfig{Type: "tdengine", Database: "metrics"},
		TargetConfig:        connection.ConnectionConfig{Type: "kingbase", Database: "ignored"},
		TargetTableStrategy: "smart",
	}
	plan, sourceCols, targetCols, err := buildTDengineToPGLikePlan(cfg, "cpu", sourceDB, targetDB)
	if err != nil {
		t.Fatalf("buildTDengineToPGLikePlan returned error: %v", err)
	}
	if len(sourceCols) != 3 || len(targetCols) != 0 {
		t.Fatalf("unexpected columns lengths: source=%d target=%d", len(sourceCols), len(targetCols))
	}
	if !plan.AutoCreate {
		t.Fatalf("expected auto create enabled")
	}
	if !strings.Contains(plan.CreateTableSQL, `CREATE TABLE "public"."cpu"`) {
		t.Fatalf("unexpected create table sql: %s", plan.CreateTableSQL)
	}
	if !strings.Contains(plan.CreateTableSQL, `"ts" timestamp`) {
		t.Fatalf("expected timestamp mapping, got: %s", plan.CreateTableSQL)
	}
	if !strings.Contains(plan.CreateTableSQL, `"payload" jsonb`) {
		t.Fatalf("expected json mapping, got: %s", plan.CreateTableSQL)
	}
	if len(plan.Warnings) == 0 || !strings.Contains(strings.Join(plan.Warnings, " "), "TAG") {
		t.Fatalf("expected TAG warning, got: %v", plan.Warnings)
	}
}

func TestBuildSchemaMigrationPlan_TDengineTargetWarnsInsertOnlyBoundary(t *testing.T) {
	t.Parallel()

	sourceDB := &fakeMigrationDB{
		columns: map[string][]connection.ColumnDefinition{
			"shop.metrics": {
				{Name: "id", Type: "bigint", Nullable: "NO", Key: "PRI"},
				{Name: "ts", Type: "datetime", Nullable: "NO"},
				{Name: "value", Type: "double", Nullable: "YES"},
			},
		},
	}
	targetDB := &fakeMigrationDB{
		columns: map[string][]connection.ColumnDefinition{
			"taos.metrics": {
				{Name: "id", Type: "bigint", Nullable: "NO"},
				{Name: "ts", Type: "timestamp", Nullable: "NO"},
				{Name: "value", Type: "double", Nullable: "YES"},
			},
		},
	}
	cfg := SyncConfig{
		SourceConfig: connection.ConnectionConfig{Type: "mysql", Database: "shop"},
		TargetConfig: connection.ConnectionConfig{Type: "tdengine", Database: "taos"},
		Mode:         "insert_update",
	}

	plan, _, _, err := buildSchemaMigrationPlan(cfg, "metrics", sourceDB, targetDB)
	if err != nil {
		t.Fatalf("buildSchemaMigrationPlan returned error: %v", err)
	}
	warnings := strings.Join(plan.Warnings, " ")
	if !strings.Contains(warnings, "仅支持 INSERT 写入") {
		t.Fatalf("expected TDengine target warning, got: %v", plan.Warnings)
	}
}

func TestBuildMySQLLikeToTDenginePlan_AutoCreateWhenTargetMissing(t *testing.T) {
	t.Parallel()

	sourceDB := &fakeMigrationDB{
		columns: map[string][]connection.ColumnDefinition{
			"shop.metrics": {
				{Name: "id", Type: "bigint", Nullable: "NO", Key: "PRI", Extra: "auto_increment"},
				{Name: "ts", Type: "datetime", Nullable: "NO"},
				{Name: "payload", Type: "json", Nullable: "YES"},
			},
		},
	}
	targetDB := &fakeMigrationDB{}
	cfg := SyncConfig{
		SourceConfig:        connection.ConnectionConfig{Type: "mysql", Database: "shop"},
		TargetConfig:        connection.ConnectionConfig{Type: "tdengine", Database: "taos"},
		TargetTableStrategy: "smart",
	}
	plan, sourceCols, targetCols, err := buildMySQLLikeToTDenginePlan(cfg, "metrics", sourceDB, targetDB)
	if err != nil {
		t.Fatalf("buildMySQLLikeToTDenginePlan returned error: %v", err)
	}
	if len(sourceCols) != 3 || len(targetCols) != 0 {
		t.Fatalf("unexpected columns lengths: source=%d target=%d", len(sourceCols), len(targetCols))
	}
	if !plan.AutoCreate {
		t.Fatalf("expected auto create enabled")
	}
	if !strings.Contains(plan.CreateTableSQL, "CREATE TABLE `taos`.`metrics`") {
		t.Fatalf("unexpected create sql: %s", plan.CreateTableSQL)
	}
	if !strings.Contains(plan.CreateTableSQL, "`ts` TIMESTAMP") {
		t.Fatalf("expected ts first column mapped to TIMESTAMP, got: %s", plan.CreateTableSQL)
	}
	if !strings.Contains(plan.CreateTableSQL, "`payload` VARCHAR(") {
		t.Fatalf("expected json degrade to VARCHAR, got: %s", plan.CreateTableSQL)
	}
	if !strings.Contains(strings.Join(plan.Warnings, " "), "insert-only") && !strings.Contains(strings.Join(plan.Warnings, " "), "INSERT") {
		t.Fatalf("expected tdengine target warning, got: %v", plan.Warnings)
	}
}

func TestBuildPGLikeToTDenginePlan_AutoCreateWhenTargetMissing(t *testing.T) {
	t.Parallel()

	sourceDB := &fakeMigrationDB{
		columns: map[string][]connection.ColumnDefinition{
			"public.metrics": {
				{Name: "event_time", Type: "timestamp without time zone", Nullable: "NO"},
				{Name: "name", Type: "character varying(64)", Nullable: "YES"},
				{Name: "meta", Type: "jsonb", Nullable: "YES"},
			},
		},
	}
	targetDB := &fakeMigrationDB{}
	cfg := SyncConfig{
		SourceConfig:        connection.ConnectionConfig{Type: "postgres", Database: "ignored"},
		TargetConfig:        connection.ConnectionConfig{Type: "tdengine", Database: "taos"},
		TargetTableStrategy: "smart",
	}
	plan, sourceCols, targetCols, err := buildPGLikeToTDenginePlan(cfg, "metrics", sourceDB, targetDB)
	if err != nil {
		t.Fatalf("buildPGLikeToTDenginePlan returned error: %v", err)
	}
	if len(sourceCols) != 3 || len(targetCols) != 0 {
		t.Fatalf("unexpected columns lengths: source=%d target=%d", len(sourceCols), len(targetCols))
	}
	if !plan.AutoCreate {
		t.Fatalf("expected auto create enabled")
	}
	if !strings.Contains(plan.CreateTableSQL, "CREATE TABLE `taos`.`metrics`") {
		t.Fatalf("unexpected create sql: %s", plan.CreateTableSQL)
	}
	if !strings.Contains(plan.CreateTableSQL, "`event_time` TIMESTAMP") {
		t.Fatalf("expected timestamp mapping, got: %s", plan.CreateTableSQL)
	}
	if !strings.Contains(plan.CreateTableSQL, "`meta` VARCHAR(") {
		t.Fatalf("expected jsonb degrade to VARCHAR, got: %s", plan.CreateTableSQL)
	}
}

func TestBuildMySQLLikeToTDenginePlan_RejectsAutoCreateWithoutTimestampColumn(t *testing.T) {
	t.Parallel()

	sourceDB := &fakeMigrationDB{
		columns: map[string][]connection.ColumnDefinition{
			"shop.metrics": {
				{Name: "id", Type: "bigint", Nullable: "NO", Key: "PRI"},
				{Name: "name", Type: "varchar(64)", Nullable: "YES"},
			},
		},
	}
	targetDB := &fakeMigrationDB{}
	cfg := SyncConfig{
		SourceConfig:        connection.ConnectionConfig{Type: "mysql", Database: "shop"},
		TargetConfig:        connection.ConnectionConfig{Type: "tdengine", Database: "taos"},
		TargetTableStrategy: "smart",
	}
	plan, _, _, err := buildMySQLLikeToTDenginePlan(cfg, "metrics", sourceDB, targetDB)
	if err != nil {
		t.Fatalf("buildMySQLLikeToTDenginePlan returned error: %v", err)
	}
	if plan.AutoCreate {
		t.Fatalf("expected auto create disabled when source has no timestamp column")
	}
	if !strings.Contains(plan.PlannedAction, "时间列") {
		t.Fatalf("unexpected planned action: %s", plan.PlannedAction)
	}
	if !strings.Contains(strings.Join(plan.Warnings, " "), "时间列") {
		t.Fatalf("expected missing timestamp warning, got: %v", plan.Warnings)
	}
}

func TestBuildClickHouseToTDenginePlan_AutoCreateWhenTargetMissing(t *testing.T) {
	t.Parallel()

	sourceDB := &fakeMigrationDB{
		columns: map[string][]connection.ColumnDefinition{
			"analytics.metrics": {
				{Name: "event_time", Type: "DateTime64(3)", Nullable: "NO"},
				{Name: "host", Type: "FixedString(64)", Nullable: "YES"},
				{Name: "payload", Type: "Map(String,String)", Nullable: "YES"},
			},
		},
	}
	targetDB := &fakeMigrationDB{}
	cfg := SyncConfig{
		SourceConfig:        connection.ConnectionConfig{Type: "clickhouse", Database: "analytics"},
		TargetConfig:        connection.ConnectionConfig{Type: "tdengine", Database: "taos"},
		TargetTableStrategy: "smart",
	}
	plan, sourceCols, targetCols, err := buildClickHouseToTDenginePlan(cfg, "metrics", sourceDB, targetDB)
	if err != nil {
		t.Fatalf("buildClickHouseToTDenginePlan returned error: %v", err)
	}
	if len(sourceCols) != 3 || len(targetCols) != 0 {
		t.Fatalf("unexpected columns lengths: source=%d target=%d", len(sourceCols), len(targetCols))
	}
	if !plan.AutoCreate {
		t.Fatalf("expected auto create enabled")
	}
	if !strings.Contains(plan.CreateTableSQL, "CREATE TABLE `taos`.`metrics`") {
		t.Fatalf("unexpected create sql: %s", plan.CreateTableSQL)
	}
	if !strings.Contains(plan.CreateTableSQL, "`event_time` TIMESTAMP") {
		t.Fatalf("expected datetime64 mapping, got: %s", plan.CreateTableSQL)
	}
	if !strings.Contains(plan.CreateTableSQL, "`host` VARCHAR(64)") {
		t.Fatalf("expected fixedstring mapping, got: %s", plan.CreateTableSQL)
	}
	if !strings.Contains(plan.CreateTableSQL, "`payload` VARCHAR(") {
		t.Fatalf("expected complex type degrade to VARCHAR, got: %s", plan.CreateTableSQL)
	}
}

func TestBuildClickHouseToPGLikePlan_AutoCreateWhenTargetMissing(t *testing.T) {
	t.Parallel()

	sourceDB := &fakeMigrationDB{
		columns: map[string][]connection.ColumnDefinition{
			"analytics.metrics": {
				{Name: "id", Type: "UInt64", Nullable: "NO", Key: "PRI"},
				{Name: "event_time", Type: "DateTime64(3)", Nullable: "NO"},
				{Name: "host", Type: "FixedString(64)", Nullable: "YES"},
				{Name: "payload", Type: "Map(String,String)", Nullable: "YES"},
			},
		},
	}
	targetDB := &fakeMigrationDB{}
	cfg := SyncConfig{
		SourceConfig:        connection.ConnectionConfig{Type: "clickhouse", Database: "analytics"},
		TargetConfig:        connection.ConnectionConfig{Type: "postgres", Database: "public"},
		TargetTableStrategy: "smart",
	}
	plan, sourceCols, targetCols, err := buildClickHouseToPGLikePlan(cfg, "metrics", sourceDB, targetDB)
	if err != nil {
		t.Fatalf("buildClickHouseToPGLikePlan returned error: %v", err)
	}
	if len(sourceCols) != 4 || len(targetCols) != 0 {
		t.Fatalf("unexpected columns lengths: source=%d target=%d", len(sourceCols), len(targetCols))
	}
	if !plan.AutoCreate {
		t.Fatalf("expected auto create enabled")
	}
	if !strings.Contains(plan.CreateTableSQL, `CREATE TABLE "public"."metrics"`) {
		t.Fatalf("unexpected create sql: %s", plan.CreateTableSQL)
	}
	if !strings.Contains(plan.CreateTableSQL, `"id" numeric(20,0)`) {
		t.Fatalf("expected uint64 safeguard mapping, got: %s", plan.CreateTableSQL)
	}
	if !strings.Contains(plan.CreateTableSQL, `"event_time" timestamp`) {
		t.Fatalf("expected datetime64 mapping, got: %s", plan.CreateTableSQL)
	}
	if !strings.Contains(plan.CreateTableSQL, `"host" varchar(64)`) {
		t.Fatalf("expected fixedstring mapping, got: %s", plan.CreateTableSQL)
	}
	if !strings.Contains(plan.CreateTableSQL, `"payload" jsonb`) {
		t.Fatalf("expected complex type degrade to jsonb, got: %s", plan.CreateTableSQL)
	}
	if !strings.Contains(plan.CreateTableSQL, `PRIMARY KEY ("id")`) {
		t.Fatalf("expected primary key preservation, got: %s", plan.CreateTableSQL)
	}
}

func TestBuildPGLikeToClickHousePlan_AutoCreateWhenTargetMissing(t *testing.T) {
	t.Parallel()

	sourceDB := &fakeMigrationDB{
		columns: map[string][]connection.ColumnDefinition{
			"public.orders": {
				{Name: "id", Type: "bigint", Nullable: "NO", Key: "PRI"},
				{Name: "created_at", Type: "timestamp without time zone", Nullable: "NO"},
				{Name: "profile", Type: "jsonb", Nullable: "YES"},
			},
		},
	}
	targetDB := &fakeMigrationDB{}
	cfg := SyncConfig{
		SourceConfig:        connection.ConnectionConfig{Type: "postgres", Database: "public"},
		TargetConfig:        connection.ConnectionConfig{Type: "clickhouse", Database: "analytics"},
		TargetTableStrategy: "smart",
	}
	plan, sourceCols, targetCols, err := buildPGLikeToClickHousePlan(cfg, "orders", sourceDB, targetDB)
	if err != nil {
		t.Fatalf("buildPGLikeToClickHousePlan returned error: %v", err)
	}
	if len(sourceCols) != 3 || len(targetCols) != 0 {
		t.Fatalf("unexpected columns lengths: source=%d target=%d", len(sourceCols), len(targetCols))
	}
	if !plan.AutoCreate {
		t.Fatalf("expected auto create enabled")
	}
	if !strings.Contains(plan.CreateTableSQL, "CREATE TABLE `analytics`.`orders`") {
		t.Fatalf("unexpected create sql: %s", plan.CreateTableSQL)
	}
	if !strings.Contains(plan.CreateTableSQL, "`created_at` DateTime") {
		t.Fatalf("expected timestamp mapping, got: %s", plan.CreateTableSQL)
	}
	if !strings.Contains(plan.CreateTableSQL, "`profile` Nullable(String)") {
		t.Fatalf("expected jsonb degrade to Nullable(String), got: %s", plan.CreateTableSQL)
	}
	if !strings.Contains(plan.CreateTableSQL, "ORDER BY (`id`)") {
		t.Fatalf("expected primary key order by, got: %s", plan.CreateTableSQL)
	}
}

func TestBuildTDengineToTDenginePlan_AutoCreateWhenTargetMissing(t *testing.T) {
	t.Parallel()

	sourceDB := &fakeMigrationDB{
		columns: map[string][]connection.ColumnDefinition{
			"src.cpu": {
				{Name: "ts", Type: "TIMESTAMP", Nullable: "NO"},
				{Name: "host", Type: "NCHAR(64)", Nullable: "YES"},
				{Name: "region", Type: "NCHAR(32)", Nullable: "YES", Key: "TAG"},
			},
		},
	}
	targetDB := &fakeMigrationDB{}
	cfg := SyncConfig{
		SourceConfig:        connection.ConnectionConfig{Type: "tdengine", Database: "src"},
		TargetConfig:        connection.ConnectionConfig{Type: "tdengine", Database: "dst"},
		TargetTableStrategy: "smart",
	}
	plan, sourceCols, targetCols, err := buildTDengineToTDenginePlan(cfg, "cpu", sourceDB, targetDB)
	if err != nil {
		t.Fatalf("buildTDengineToTDenginePlan returned error: %v", err)
	}
	if len(sourceCols) != 3 || len(targetCols) != 0 {
		t.Fatalf("unexpected columns lengths: source=%d target=%d", len(sourceCols), len(targetCols))
	}
	if !plan.AutoCreate {
		t.Fatalf("expected auto create enabled")
	}
	if !strings.Contains(plan.CreateTableSQL, "CREATE TABLE `dst`.`cpu`") {
		t.Fatalf("unexpected create sql: %s", plan.CreateTableSQL)
	}
	if !strings.Contains(plan.CreateTableSQL, "`ts` TIMESTAMP") {
		t.Fatalf("expected timestamp preserved, got: %s", plan.CreateTableSQL)
	}
	if !strings.Contains(plan.CreateTableSQL, "`region` NCHAR(32)") {
		t.Fatalf("expected tag degrade to regular nchar column, got: %s", plan.CreateTableSQL)
	}
	if !strings.Contains(strings.Join(plan.Warnings, " "), "TAG") {
		t.Fatalf("expected TAG degrade warning, got: %v", plan.Warnings)
	}
}