package app

import (
	"errors"
	"strings"
	"testing"

	"GoNavi-Wails/internal/connection"
)

type fakeCreateStatementDB struct {
	createSQL  string
	createErr  error
	columns    []connection.ColumnDefinition
	columnsErr error
	queryRows  []map[string]interface{}
	queryErr   error

	createSchema string
	createTable  string
	colsSchema   string
	colsTable    string
	columnsCalls int
	queries      []string
}

func (f *fakeCreateStatementDB) Connect(config connection.ConnectionConfig) error { return nil }
func (f *fakeCreateStatementDB) Close() error                                     { return nil }
func (f *fakeCreateStatementDB) Ping() error                                      { return nil }
func (f *fakeCreateStatementDB) Query(query string) ([]map[string]interface{}, []string, error) {
	f.queries = append(f.queries, query)
	return f.queryRows, []string{"ddl"}, f.queryErr
}
func (f *fakeCreateStatementDB) Exec(query string) (int64, error)          { return 0, nil }
func (f *fakeCreateStatementDB) GetDatabases() ([]string, error)           { return nil, nil }
func (f *fakeCreateStatementDB) GetTables(dbName string) ([]string, error) { return nil, nil }
func (f *fakeCreateStatementDB) GetCreateStatement(dbName, tableName string) (string, error) {
	f.createSchema = dbName
	f.createTable = tableName
	return f.createSQL, f.createErr
}
func (f *fakeCreateStatementDB) GetColumns(dbName, tableName string) ([]connection.ColumnDefinition, error) {
	f.columnsCalls++
	f.colsSchema = dbName
	f.colsTable = tableName
	return f.columns, f.columnsErr
}
func (f *fakeCreateStatementDB) GetAllColumns(dbName string) ([]connection.ColumnDefinitionWithTable, error) {
	return nil, nil
}
func (f *fakeCreateStatementDB) GetIndexes(dbName, tableName string) ([]connection.IndexDefinition, error) {
	return nil, nil
}
func (f *fakeCreateStatementDB) GetForeignKeys(dbName, tableName string) ([]connection.ForeignKeyDefinition, error) {
	return nil, nil
}
func (f *fakeCreateStatementDB) GetTriggers(dbName, tableName string) ([]connection.TriggerDefinition, error) {
	return nil, nil
}

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

	testCases := []struct {
		name   string
		driver string
		want   string
	}{
		{name: "postgresql alias", driver: "postgresql", want: "postgres"},
		{name: "pgx alias", driver: "pgx", want: "postgres"},
		{name: "kingbase8 alias", driver: "kingbase8", want: "kingbase"},
		{name: "kingbase contains alias", driver: "kingbasees", want: "kingbase"},
		{name: "dm alias", driver: "dm8", want: "dameng"},
		{name: "sqlite alias", driver: "sqlite3", want: "sqlite"},
	}

	for _, tc := range testCases {
		tc := tc
		t.Run(tc.name, func(t *testing.T) {
			t.Parallel()
			cfg := connection.ConnectionConfig{Type: "custom", Driver: tc.driver}
			if got := resolveDDLDBType(cfg); got != tc.want {
				t.Fatalf("resolveDDLDBType() mismatch, want=%q got=%q", tc.want, got)
			}
		})
	}
}

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

	tests := []struct {
		name       string
		dbType     string
		tableName  string
		wantSchema string
		wantTable  string
	}{
		{name: "postgres quoted dots", dbType: "postgres", tableName: `"sales.schema"."order.items"`, wantSchema: "sales.schema", wantTable: "order.items"},
		{name: "highgo escaped quoted", dbType: "highgo", tableName: `\"sales\".\"orders\"`, wantSchema: "sales", wantTable: "orders"},
		{name: "vastbase quoted table only", dbType: "vastbase", tableName: `"order.items"`, wantSchema: "public", wantTable: "order.items"},
	}

	for _, tt := range tests {
		tt := tt
		t.Run(tt.name, func(t *testing.T) {
			t.Parallel()
			gotSchema, gotTable := normalizeSchemaAndTableByType(tt.dbType, "", tt.tableName)
			if gotSchema != tt.wantSchema || gotTable != tt.wantTable {
				t.Fatalf("normalizeSchemaAndTableByType(%q,%q)=(%q,%q),want=(%q,%q)", tt.dbType, tt.tableName, gotSchema, gotTable, tt.wantSchema, tt.wantTable)
			}
		})
	}
}

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

	got := buildRunConfigForDDL(connection.ConnectionConfig{
		Type:     "custom",
		Driver:   "highgo",
		Database: "default_db",
	}, "highgo", "target_db")
	if got.Database != "target_db" {
		t.Fatalf("expected custom highgo DDL database target_db, got %q", got.Database)
	}
}

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

	dbInst := &fakeCreateStatementDB{
		createSQL: "SHOW CREATE TABLE not directly supported in Kingbase/Postgres via SQL",
		columns: []connection.ColumnDefinition{
			{Name: "id", Type: "bigint", Nullable: "NO", Key: "PRI"},
		},
	}

	ddl, err := resolveCreateStatementWithFallback(dbInst, connection.ConnectionConfig{
		Type:   "custom",
		Driver: "kingbase8",
	}, "demo_db", "orders")
	if err != nil {
		t.Fatalf("resolveCreateStatementWithFallback() unexpected error: %v", err)
	}
	if dbInst.createSchema != "public" || dbInst.colsSchema != "public" {
		t.Fatalf("expected fallback schema public, got create=%q columns=%q", dbInst.createSchema, dbInst.colsSchema)
	}
	if !strings.Contains(ddl, `CREATE TABLE "public"."orders"`) {
		t.Fatalf("expected fallback DDL with public schema, got: %s", ddl)
	}
}

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

	dbInst := &fakeCreateStatementDB{
		createSQL: "-- SHOW CREATE TABLE not fully supported for PostgreSQL in this MVP.",
		columns: []connection.ColumnDefinition{
			{Name: "id", Type: "integer", Nullable: "NO", Key: "PRI"},
		},
	}

	ddl, err := resolveCreateStatementWithFallback(dbInst, connection.ConnectionConfig{
		Type:   "custom",
		Driver: "postgresql",
	}, "demo_db", "sales.orders")
	if err != nil {
		t.Fatalf("resolveCreateStatementWithFallback() unexpected error: %v", err)
	}
	if dbInst.createSchema != "sales" || dbInst.colsSchema != "sales" {
		t.Fatalf("expected schema sales, got create=%q columns=%q", dbInst.createSchema, dbInst.colsSchema)
	}
	if !strings.Contains(ddl, `CREATE TABLE "sales"."orders"`) {
		t.Fatalf("expected fallback DDL with sales schema, got: %s", ddl)
	}
}

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

	dbInst := &fakeCreateStatementDB{
		createSQL: "-- SHOW CREATE TABLE not fully supported for PostgreSQL in this MVP.",
		columns: []connection.ColumnDefinition{
			{Name: "id", Type: "integer", Nullable: "NO", Key: "PRI"},
		},
	}

	ddl, err := resolveCreateStatementWithFallback(dbInst, connection.ConnectionConfig{
		Type: "postgres",
	}, "", `"sales.schema"."order.items"`)
	if err != nil {
		t.Fatalf("resolveCreateStatementWithFallback() unexpected error: %v", err)
	}
	if dbInst.createSchema != "sales.schema" || dbInst.createTable != "order.items" {
		t.Fatalf("expected create target sales.schema.order.items, got %q.%q", dbInst.createSchema, dbInst.createTable)
	}
	if dbInst.colsSchema != "sales.schema" || dbInst.colsTable != "order.items" {
		t.Fatalf("expected column target sales.schema.order.items, got %q.%q", dbInst.colsSchema, dbInst.colsTable)
	}
	if !strings.Contains(ddl, `CREATE TABLE "sales.schema"."order.items"`) {
		t.Fatalf("expected fallback DDL with quoted dotted identifiers, got: %s", ddl)
	}
}

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

	dbInst := &fakeCreateStatementDB{
		createSQL:  "CREATE VIEW sales.orders_v AS SELECT 1;",
		columnsErr: errors.New("should not be called"),
	}

	ddl, err := resolveCreateStatementWithFallback(dbInst, connection.ConnectionConfig{Type: "postgres"}, "", "sales.orders_v")
	if err != nil {
		t.Fatalf("resolveCreateStatementWithFallback() unexpected error: %v", err)
	}
	if ddl != dbInst.createSQL {
		t.Fatalf("expected original create view DDL, got: %s", ddl)
	}
	if dbInst.columnsCalls != 0 {
		t.Fatalf("CREATE VIEW path should not call GetColumns, calls=%d", dbInst.columnsCalls)
	}
}

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

	dbInst := &fakeCreateStatementDB{
		createSQL:  "SHOW CREATE TABLE not directly supported in PostgreSQL",
		columnsErr: errors.New("should not be called"),
		queryRows: []map[string]interface{}{
			{"ddl": "SELECT id FROM sales.orders"},
		},
	}

	ddl, err := resolveCreateStatementWithFallback(dbInst, connection.ConnectionConfig{Type: "postgres"}, "", "sales.orders_v")
	if err != nil {
		t.Fatalf("resolveCreateStatementWithFallback() unexpected error: %v", err)
	}
	if !strings.Contains(ddl, `CREATE VIEW "sales"."orders_v" AS SELECT id FROM sales.orders`) {
		t.Fatalf("expected CREATE VIEW DDL from view helper, got: %s", ddl)
	}
	if dbInst.columnsCalls != 0 {
		t.Fatalf("view helper path should not call GetColumns, calls=%d", dbInst.columnsCalls)
	}
	if len(dbInst.queries) == 0 || !strings.Contains(dbInst.queries[0], "pg_get_viewdef") {
		t.Fatalf("expected pg_get_viewdef query, got: %v", dbInst.queries)
	}
}

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

	dbInst := &fakeCreateStatementDB{
		createSQL:  "SHOW CREATE TABLE not directly supported in PostgreSQL",
		columnsErr: errors.New("should not be called"),
		queryRows: []map[string]interface{}{
			{"ddl": "SELECT 1"},
		},
	}

	ddl, err := resolveCreateStatementWithFallback(dbInst, connection.ConnectionConfig{Type: "postgres"}, "", `"sales.schema"."order.items"`)
	if err != nil {
		t.Fatalf("resolveCreateStatementWithFallback() unexpected error: %v", err)
	}
	if !strings.Contains(ddl, `CREATE VIEW "sales.schema"."order.items" AS SELECT 1`) {
		t.Fatalf("expected CREATE VIEW DDL to keep quoted dotted identifiers, got: %s", ddl)
	}
	if dbInst.columnsCalls != 0 {
		t.Fatalf("view helper path should not call GetColumns, calls=%d", dbInst.columnsCalls)
	}
}

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

	dbInst := &fakeCreateStatementDB{
		createSQL: "SHOW CREATE TABLE not directly supported in PostgreSQL",
		columns: []connection.ColumnDefinition{
			{Name: "id", Type: "bigint", Nullable: "NO", Key: "PRI"},
		},
	}

	ddl, err := resolveCreateStatementWithFallback(dbInst, connection.ConnectionConfig{Type: "postgres"}, "", "sales.orders")
	if err != nil {
		t.Fatalf("resolveCreateStatementWithFallback() unexpected error: %v", err)
	}
	if !strings.Contains(ddl, `CREATE TABLE "sales"."orders"`) {
		t.Fatalf("expected CREATE TABLE fallback after view helper miss, got: %s", ddl)
	}
	if dbInst.columnsCalls != 1 {
		t.Fatalf("expected one GetColumns call after view helper miss, calls=%d", dbInst.columnsCalls)
	}
}

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

	dbInst := &fakeCreateStatementDB{
		createSQL:  "SHOW CREATE TABLE not directly supported in Kingbase/Postgres via SQL",
		columnsErr: errors.New("should not be called"),
	}

	ddl, err := resolveCreateStatementWithFallback(dbInst, connection.ConnectionConfig{
		Type: "mysql",
	}, "demo_db", "orders")
	if err != nil {
		t.Fatalf("resolveCreateStatementWithFallback() unexpected error: %v", err)
	}
	if ddl != dbInst.createSQL {
		t.Fatalf("expected original ddl for mysql, got: %s", ddl)
	}
	if dbInst.colsTable != "" {
		t.Fatalf("mysql path should not call GetColumns, got table=%q", dbInst.colsTable)
	}
}

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

	dbInst := &fakeCreateStatementDB{
		createErr: errors.New("statement unsupported"),
		columns: []connection.ColumnDefinition{
			{Name: "id", Type: "bigint", Nullable: "NO", Key: "PRI"},
		},
	}

	ddl, err := resolveCreateStatementWithFallback(dbInst, connection.ConnectionConfig{
		Type: "postgres",
	}, "demo_db", "orders")
	if err != nil {
		t.Fatalf("resolveCreateStatementWithFallback() unexpected error: %v", err)
	}
	if !strings.Contains(ddl, `CREATE TABLE "public"."orders"`) {
		t.Fatalf("expected fallback DDL for postgres error path, got: %s", ddl)
	}
}