cash-code-test/workflow/app.go

package workflow

import (
	"bufio"
	"fmt"
	"github.com/wahyd4/cash/commands"
	"github.com/wahyd4/cash/domains"
	"os"
	"strconv"
	"strings"
)

const commandSplitter = " "

// APP holds the bank app instance
type APP struct {
	Bank *domains.Bank
}

// Run all the commands passed in
func (app *APP) Run(commands []commands.ICommand) error {
	for _, command := range commands {
		if err := command.Run(app.Bank); err != nil {
			return err
		}
	}
	return nil
}

// Load loads inputs and generate commands
func (app *APP) Load(filePath string) ([]commands.ICommand, error) {
	appCommands := make([]commands.ICommand, 0)

	file, err := os.Open(filePath)
	if err != nil {
		return appCommands, err
	}
	defer file.Close()

	scanner := bufio.NewScanner(file)
	for scanner.Scan() {
		commandString := scanner.Text()
		appCommands = append(appCommands, buildCommand(commandString))
	}

	if err := scanner.Err(); err != nil {
		return nil, fmt.Errorf("fail to read file %s with error: %v", filePath, err)
	}

	return appCommands, nil
}

func buildCommand(commandString string) commands.ICommand {

	commandArgs := strings.Split(commandString, commandSplitter)
	switch commandArgs[0] {
	case "OPEN_ACCOUNT":
		return &commands.OpenAccountCommand{Username: commandArgs[1]}
	case "DEPOSIT":
		money, _ := strconv.ParseFloat(commandArgs[2], 10)
		return &commands.DepositCommand{
			Account: commandArgs[1],
			Money:   money,
		}
	case "WITHDRAW":
		money, _ := strconv.ParseFloat(commandArgs[2], 10)
		return &commands.WithdrawCommand{
			Account: commandArgs[1],
			Money:   money,
		}
	case "BALANCE":
		return &commands.UserBalanceCommand{
			Account: commandArgs[1],
		}
	case "TOTAL_BALANCE":
		return &commands.TotalBalanceCommand{}
	default:
		return &commands.TotalBalanceCommand{}
	}
}