package banking

import (
	"context"
	"fmt"
	"io"
	"math/rand/v2"
	"time"

	tea "github.com/charmbracelet/bubbletea"

	"git.t-juice.club/torjus/oubliette/internal/shell"
)

const sessionTimeout = 10 * time.Minute

// BankingShell is an 80s-style green-on-black bank terminal TUI.
type BankingShell struct{}

// NewBankingShell returns a new BankingShell instance.
func NewBankingShell() *BankingShell {
	return &BankingShell{}
}

func (b *BankingShell) Name() string        { return "banking" }
func (b *BankingShell) Description() string { return "80s-style banking terminal TUI" }

func (b *BankingShell) Handle(ctx context.Context, sess *shell.SessionContext, rw io.ReadWriteCloser) error {
	ctx, cancel := context.WithTimeout(ctx, sessionTimeout)
	defer cancel()

	bankName := configString(sess.ShellConfig, "bank_name", "SECUREBANK")
	terminalID := configString(sess.ShellConfig, "terminal_id", "")
	region := configString(sess.ShellConfig, "region", "NORTHEAST")

	if terminalID == "" {
		terminalID = fmt.Sprintf("SB-%04d", rand.IntN(10000))
	}

	m := newModel(sess, bankName, terminalID, region)
	p := tea.NewProgram(m,
		tea.WithInput(rw),
		tea.WithOutput(rw),
		tea.WithAltScreen(),
	)

	done := make(chan error, 1)
	go func() {
		_, err := p.Run()
		done <- err
	}()

	select {
	case err := <-done:
		return err
	case <-ctx.Done():
		p.Quit()
		<-done
		return nil
	}
}

// configString reads a string from the shell config map with a default.
func configString(cfg map[string]any, key, defaultVal string) string {
	if cfg == nil {
		return defaultVal
	}
	if v, ok := cfg[key]; ok {
		if s, ok := v.(string); ok && s != "" {
			return s
		}
	}
	return defaultVal
}