Move main back to root folder.

- Change everything to package main.
- Make main a little more user friendly.

main.go

@@ -0,0 +1,112 @@
+// Package main defines a command line interface for the sqlboiler package
+package main
+
+import (
+	"errors"
+	"fmt"
+	"os"
+	"path/filepath"
+
+	"github.com/spf13/cobra"
+	"github.com/spf13/viper"
+)
+
+var (
+	cmdState  *State
+	cmdConfig *Config
+)
+
+func main() {
+	var err error
+
+	viper.SetConfigName("sqlboiler")
+
+	configHome := os.Getenv("XDG_CONFIG_HOME")
+	homePath := os.Getenv("HOME")
+	wd, err := os.Getwd()
+	if err != nil {
+		wd = "./"
+	}
+
+	configPaths := []string{wd}
+	if len(configHome) > 0 {
+		configPaths = append(configPaths, filepath.Join(configHome, "sqlboiler"))
+	} else {
+		configPaths = append(configPaths, filepath.Join(homePath, ".config/sqlboiler"))
+	}
+
+	for _, p := range configPaths {
+		viper.AddConfigPath(p)
+	}
+
+	// Find and read config
+	err = viper.ReadInConfig()
+
+	// Set up the cobra root command
+	var rootCmd = &cobra.Command{
+		Use:   "sqlboiler [options] <driver>",
+		Short: "SQL Boiler generates boilerplate structs and statements",
+		Long: "SQL Boiler generates boilerplate structs and statements from template files.\n" +
+			`Complete documentation is available at http://github.com/nullbio/sqlboiler`,
+		Example:  `sqlboiler -o mymodels -p mymodelpackage postgres`,
+		PreRunE:  preRun,
+		RunE:     run,
+		PostRunE: postRun,
+	}
+
+	// Set up the cobra root command flags
+	rootCmd.PersistentFlags().StringSliceP("table", "t", nil, "Tables to generate models for, all tables if empty")
+	rootCmd.PersistentFlags().StringP("output", "o", "output", "The name of the folder to output to")
+	rootCmd.PersistentFlags().StringP("pkgname", "p", "model", "The name you wish to assign to your generated package")
+
+	viper.BindPFlags(rootCmd.PersistentFlags())
+
+	if err := rootCmd.Execute(); err != nil {
+		fmt.Println("Failed to execute sqlboiler command:", err)
+		os.Exit(-1)
+	}
+}
+
+func preRun(cmd *cobra.Command, args []string) error {
+	if len(args) == 0 {
+		_ = cmd.Help()
+		fmt.Println("\nmust provide a driver")
+		os.Exit(1)
+	}
+
+	cmdConfig = new(Config)
+
+	cmdConfig.DriverName = args[0]
+	cmdConfig.TableName = viper.GetString("table")
+	cmdConfig.OutFolder = viper.GetString("folder")
+	cmdConfig.PkgName = viper.GetString("pkgname")
+
+	if len(cmdConfig.DriverName) == 0 {
+		return errors.New("Must supply a driver flag.")
+	}
+	if len(cmdConfig.OutFolder) == 0 {
+		return fmt.Errorf("No output folder specified.")
+	}
+
+	if viper.IsSet("postgres.dbname") {
+		cmdConfig.Postgres = PostgresConfig{
+			User:   viper.GetString("postgres.user"),
+			Pass:   viper.GetString("postgres.pass"),
+			Host:   viper.GetString("postgres.host"),
+			Port:   viper.GetInt("postgres.port"),
+			DBName: viper.GetString("postgres.dbname"),
+		}
+	}
+
+	var err error
+	cmdState, err = New(cmdConfig)
+	return err
+}
+
+func run(cmd *cobra.Command, args []string) error {
+	return cmdState.Run(true)
+}
+
+func postRun(cmd *cobra.Command, args []string) error {
+	return cmdState.Cleanup()
+}