fraenky8 / tables-to-go

package settings

import (

	"fmt"

	"os"

	"path/filepath"

)

// These database types are supported.

const (

	DbTypePostgresql DbType = "pg"

	DbTypeMySQL      DbType = "mysql"

)

// DbType represents a type of a database.

type DbType string

// Set sets the datatype for the custom type for the flag package.

func (db *DbType) Set(s string) error {

	*db = DbType(s)

	if *db == "" {

		*db = DbTypePostgresql

	}

	if !SupportedDbTypes[*db] {

		return fmt.Errorf("type of database %q not supported! supported: %v", *db, SprintfSupportedDbTypes())

	}

	return nil

}

// String is the implementation of the Stringer interface needed for flag.Value interface.

func (db DbType) String() string {

	return string(db)

}

// These null types are supported. The types native and primitive map to the same

// underlying builtin golang type.

const (

	NullTypeSQL       NullType = "sql"

	NullTypeNative    NullType = "native"

	NullTypePrimitive NullType = "primitive"

)

// NullType represents a null type.

type NullType string

// Set sets the datatype for the custom type for the flag package.

func (t *NullType) Set(s string) error {

	*t = NullType(s)

	if *t == "" {

		*t = NullTypeSQL

	}

	if !supportedNullTypes[*t] {

		return fmt.Errorf("null type %q not supported! supported: %v", *t, SprintfSupportedNullTypes())

	}

	return nil

}

// String is the implementation of the Stringer interface needed for flag.Value interface.

func (t NullType) String() string {

	return string(t)

}

// These are the output format command line parameter.

const (

	OutputFormatCamelCase OutputFormat = "c"

	OutputFormatOriginal  OutputFormat = "o"

)

// OutputFormat represents a output format option.

type OutputFormat string

// Set sets the datatype for the custom type for the flag package.

func (of *OutputFormat) Set(s string) error {

	*of = OutputFormat(s)

	if *of == "" {

		*of = OutputFormatCamelCase

	}

	if !supportedOutputFormats[*of] {

		return fmt.Errorf("output format %q not supported", *of)

	}

	return nil

}

// String is the implementation of the Stringer interface needed for flag.Value interface.

func (of OutputFormat) String() string {

	return string(of)

}

var (

	// SupportedDbTypes represents the supported databases

	SupportedDbTypes = map[DbType]bool{

		DbTypePostgresql: true,

		DbTypeMySQL:      true,

	}

	// supportedOutputFormats represents the supported output formats

	supportedOutputFormats = map[OutputFormat]bool{

		OutputFormatCamelCase: true,

		OutputFormatOriginal:  true,

	}

	// dbDefaultPorts maps the database type to the default ports

	dbDefaultPorts = map[DbType]string{

		DbTypePostgresql: "5432",

		DbTypeMySQL:      "3306",

	}

	// supportedNullTypes represents the supported types of NULL types

	supportedNullTypes = map[NullType]bool{

		NullTypeSQL:       true,

		NullTypeNative:    true,

		NullTypePrimitive: true,

	}

)

// Settings stores the supported settings / command line arguments

type Settings struct {

	Verbose  bool

	VVerbose bool

	DbType DbType

	User   string

	Pswd   string

	DbName string

	Schema string

	Host   string

	Port   string

	OutputFilePath string

	OutputFormat   OutputFormat

	PackageName string

	Prefix      string

	Suffix      string

	Null        NullType

	NoInitialism bool

	TagsNoDb bool

	TagsMastermindStructable       bool

	TagsMastermindStructableOnly   bool

	IsMastermindStructableRecorder bool

	// TODO not implemented yet

	TagsGorm bool

}

// New constructs settings with default values

func New() *Settings {

	dir, err := filepath.Abs(filepath.Dir(os.Args[0]))

	if err != nil {

		dir = "."

	}

	return &Settings{

		Verbose:  false,

		VVerbose: false,

		DbType:         DbTypePostgresql,

		User:           "postgres",

		Pswd:           "",

		DbName:         "postgres",

		Schema:         "public",

		Host:           "127.0.0.1",

		Port:           "", // left blank -> is automatically determined if not set

		OutputFilePath: dir,

		OutputFormat:   OutputFormatCamelCase,

		PackageName:    "dto",

		Prefix:         "",

		Suffix:         "",

		Null:           NullTypeSQL,

		NoInitialism: false,

		TagsNoDb: false,

		TagsMastermindStructable:       false,

		TagsMastermindStructableOnly:   false,

		IsMastermindStructableRecorder: false,

		TagsGorm: false,

	}

}

// Verify verifies the settings and checks the given output paths

func (settings *Settings) Verify() (err error) {

	if err = settings.verifyOutputPath(); err != nil {

		return err

	}

	if settings.OutputFilePath, err = settings.prepareOutputPath(); err != nil {

		return err

	}

	if settings.Port == "" {

		settings.Port = dbDefaultPorts[settings.DbType]

	}

	if settings.PackageName == "" {

		return fmt.Errorf("name of package can not be empty")

	}

	if settings.VVerbose {

		settings.Verbose = true

	}

	return err

}

func (settings *Settings) verifyOutputPath() (err error) {

	info, err := os.Stat(settings.OutputFilePath)

	if os.IsNotExist(err) {

		return fmt.Errorf("output file path %q does not exists", settings.OutputFilePath)

	}

	if !info.Mode().IsDir() {

		return fmt.Errorf("output file path %q is not a directory", settings.OutputFilePath)

	}

	return err

}

func (settings *Settings) prepareOutputPath() (outputFilePath string, err error) {

	outputFilePath, err = filepath.Abs(settings.OutputFilePath)

	outputFilePath += string(filepath.Separator)

	return outputFilePath, err

}

// SprintfSupportedDbTypes returns a slice of strings as names of the supported database types

func SprintfSupportedDbTypes() string {

	names := make([]string, 0, len(SupportedDbTypes))

	for name := range SupportedDbTypes {

		names = append(names, string(name))

	}

	return fmt.Sprintf("%v", names)

}

// SprintfSupportedNullTypes returns a slice of strings as names of the supported null types

func SprintfSupportedNullTypes() string {

	names := make([]string, 0, len(supportedNullTypes))

	for name := range supportedNullTypes {

		names = append(names, string(name))

	}

	return fmt.Sprintf("%v", names)

}

// IsNullTypeSQL returns true if the type given by the command line args is of null type SQL

func (settings *Settings) IsNullTypeSQL() bool {

	return settings.Null == NullTypeSQL

}

// ShouldInitialism returns wheather or not if column names should be converted

// to initialisms.

func (settings *Settings) ShouldInitialism() bool {

	return !settings.NoInitialism

}

// IsOutputFormatCamelCase returns if the type given by command line args is of camel-case format.

func (settings *Settings) IsOutputFormatCamelCase() bool {

	return settings.OutputFormat == OutputFormatCamelCase

}