package screens

import (
	"strings"

	"github.com/calmcacil/wg-admin/internal/tui/theme"
	tea "github.com/charmbracelet/bubbletea"
	"github.com/charmbracelet/lipgloss"
)

// ErrorScreen displays user-friendly error messages with recovery options
type ErrorScreen struct {
	err      error
	friendly string
	actions  []ErrorAction
	quitting bool
}

// ErrorAction represents a recovery action
type ErrorAction struct {
	Key         string
	Label       string
	Description string
}

// NewErrorScreen creates a new error screen with mapped error information
func NewErrorScreen(err error) *ErrorScreen {
	screen := &ErrorScreen{
		err:      err,
		friendly: err.Error(), // Fallback to raw error
		actions:  []ErrorAction{{Key: "enter", Label: "OK", Description: "Dismiss and return"}},
		quitting: false,
	}

	// Map error to user-friendly message and recovery options
	screen.mapError(err)

	return screen
}

// Init initializes the error screen
func (s *ErrorScreen) Init() tea.Cmd {
	return nil
}

// Update handles messages for the error screen
func (s *ErrorScreen) Update(msg tea.Msg) (Screen, tea.Cmd) {
	switch msg := msg.(type) {
	case tea.KeyMsg:
		switch msg.String() {
		case "q", "ctrl+c":
			// Quit application
			s.quitting = true
			return s, tea.Quit
		case "enter", "esc":
			// Dismiss error screen
			return nil, nil
		}
	}
	return s, nil
}

// View renders the error screen
func (s *ErrorScreen) View() string {
	if s.quitting {
		return ""
	}

	titleStyle := theme.StyleTitle.Copy().MarginBottom(1)
	errorStyle := theme.StyleError.Copy().Bold(true)
	msgStyle := theme.StyleSubtitle.Copy().MarginTop(1).MarginBottom(2)
	actionTitleStyle := theme.StylePrimary.Copy().Bold(true).MarginTop(1)
	actionStyle := theme.StyleMuted.Copy().MarginLeft(2)

	// Build the error display
	content := lipgloss.JoinVertical(
		lipgloss.Left,
		titleStyle.Render("Error Occurred"),
		errorStyle.Render("⚠ "+s.friendly),
		msgStyle.Render("Technical Details: "+s.err.Error()),
	)

	// Add recovery actions
	if len(s.actions) > 1 {
		content += "\n" + actionTitleStyle.Render("Recovery Options:")
		for _, action := range s.actions {
			key := theme.StyleHelpKey.Render("[" + action.Key + "]")
			content += "\n" + actionStyle.Render(
				lipgloss.JoinHorizontal(lipgloss.Left,
					key+" ",
					action.Label+" - "+action.Description,
				),
			)
		}
	}

	content += "\n\n" + theme.StyleMuted.Render("Press Enter to dismiss • Press q to quit")

	return lipgloss.NewStyle().
		Padding(1, 2).
		Border(lipgloss.RoundedBorder()).
		BorderForeground(theme.GetCurrentTheme().Scheme.Error).
		Render(content)
}

// mapError converts technical errors to user-friendly messages and recovery options
func (s *ErrorScreen) mapError(err error) {
	if err == nil {
		return
	}

	errStr := strings.ToLower(err.Error())

	// Permission errors
	if strings.Contains(errStr, "permission") ||
		strings.Contains(errStr, "denied") ||
		strings.Contains(errStr, "operation not permitted") {
		s.friendly = "Permission Denied"
		s.actions = []ErrorAction{
			{Key: "r", Label: "Run with sudo", Description: "Restart with elevated privileges"},
			{Key: "enter", Label: "Dismiss", Description: "Return to previous screen"},
		}
		return
	}

	// File not found errors
	if strings.Contains(errStr, "no such file") ||
		strings.Contains(errStr, "file not found") ||
		strings.Contains(errStr, "does not exist") {
		s.friendly = "Configuration File Missing"
		s.actions = []ErrorAction{
			{Key: "r", Label: "Restore", Description: "Restore from backup (if available)"},
			{Key: "enter", Label: "Dismiss", Description: "Return to previous screen"},
		}
		return
	}

	// Client already exists errors
	if strings.Contains(errStr, "already exists") ||
		strings.Contains(errStr, "duplicate") {
		s.friendly = "Client Already Exists"
		s.actions = []ErrorAction{
			{Key: "n", Label: "New Name", Description: "Try a different client name"},
			{Key: "enter", Label: "Dismiss", Description: "Return to previous screen"},
		}
		return
	}

	// IP address exhaustion
	if strings.Contains(errStr, "no available") ||
		strings.Contains(errStr, "exhausted") ||
		strings.Contains(errStr, "out of") {
		s.friendly = "No Available IP Addresses"
		s.actions = []ErrorAction{
			{Key: "d", Label: "Delete Client", Description: "Remove an unused client to free IPs"},
			{Key: "enter", Label: "Dismiss", Description: "Return to previous screen"},
		}
		return
	}

	// Config file parsing errors
	if strings.Contains(errStr, "parse") ||
		strings.Contains(errStr, "invalid") ||
		strings.Contains(errStr, "malformed") {
		s.friendly = "Invalid Configuration"
		s.actions = []ErrorAction{
			{Key: "r", Label: "Restore", Description: "Restore from backup"},
			{Key: "m", Label: "Manual Fix", Description: "Edit configuration manually"},
			{Key: "enter", Label: "Dismiss", Description: "Return to previous screen"},
		}
		return
	}

	// WireGuard command failures
	if strings.Contains(errStr, "wg genkey") ||
		strings.Contains(errStr, "wg pubkey") ||
		strings.Contains(errStr, "wg genpsk") ||
		strings.Contains(errStr, "wg set") {
		s.friendly = "WireGuard Command Failed"
		s.actions = []ErrorAction{
			{Key: "i", Label: "Install WG", Description: "Ensure WireGuard is installed"},
			{Key: "s", Label: "Check Service", Description: "Verify WireGuard service is running"},
			{Key: "enter", Label: "Dismiss", Description: "Return to previous screen"},
		}
		return
	}

	// Network errors
	if strings.Contains(errStr, "network") ||
		strings.Contains(errStr, "connection") ||
		strings.Contains(errStr, "timeout") {
		s.friendly = "Network Error"
		s.actions = []ErrorAction{
			{Key: "r", Label: "Retry", Description: "Attempt the operation again"},
			{Key: "c", Label: "Check Connection", Description: "Verify network connectivity"},
			{Key: "enter", Label: "Dismiss", Description: "Return to previous screen"},
		}
		return
	}

	// Config directory not found
	if strings.Contains(errStr, "config directory") ||
		strings.Contains(errStr, "wireguard") {
		s.friendly = "WireGuard Not Configured"
		s.actions = []ErrorAction{
			{Key: "i", Label: "Install WireGuard", Description: "Set up WireGuard on this server"},
			{Key: "enter", Label: "Dismiss", Description: "Return to previous screen"},
		}
		return
	}

	// DNS validation errors
	if strings.Contains(errStr, "dns") ||
		strings.Contains(errStr, "invalid address") {
		s.friendly = "Invalid DNS Configuration"
		s.actions = []ErrorAction{
			{Key: "e", Label: "Edit DNS", Description: "Update DNS server settings"},
			{Key: "d", Label: "Use Default", Description: "Use default DNS (8.8.8.8, 8.8.4.4)"},
			{Key: "enter", Label: "Dismiss", Description: "Return to previous screen"},
		}
		return
	}

	// Backup/restore errors
	if strings.Contains(errStr, "backup") ||
		strings.Contains(errStr, "restore") {
		s.friendly = "Backup Operation Failed"
		s.actions = []ErrorAction{
			{Key: "r", Label: "Retry", Description: "Attempt backup/restore again"},
			{Key: "c", Label: "Check Space", Description: "Verify disk space is available"},
			{Key: "enter", Label: "Dismiss", Description: "Return to previous screen"},
		}
		return
	}

	// Default: generic error
	s.friendly = "An Error Occurred"
	s.actions = []ErrorAction{
		{Key: "r", Label: "Retry", Description: "Attempt the operation again"},
		{Key: "enter", Label: "Dismiss", Description: "Return to previous screen"},
	}
}