package ui

import (
	"errors"
	"fmt"

	"gioui.org/layout"
	"gioui.org/widget"
	"gioui.org/widget/material"

	"git.wxccs.org/iceking2nd/winauth-go/internal/config"
	"git.wxccs.org/iceking2nd/winauth-go/internal/global"
	"git.wxccs.org/iceking2nd/winauth-go/internal/i18n"
)

// restoreBackupDialog loads an encrypted .winauth.bak file produced by the
// export dialog. The user supplies the path and the backup's password; on
// success the loaded entries are handed back to the caller for merging.
type restoreBackupDialog struct {
	pathEd   widget.Editor
	pwEd     widget.Editor
	restoreB widget.Clickable
	cancelB  widget.Clickable

	errorMsg string
}

func newRestoreBackupDialog() *restoreBackupDialog {
	d := &restoreBackupDialog{}
	d.pathEd.SingleLine = true
	d.pwEd.SingleLine = true
	d.pwEd.Mask = '*'
	return d
}

// restoreBackupResult carries the outcome of the dialog.
type restoreBackupResult struct {
	cfg    *config.Config
	cancel bool
}

func (d *restoreBackupDialog) Layout(
	gtx layout.Context, th *material.Theme,
	onDone func(restoreBackupResult),
) layout.Dimensions {
	if d.cancelB.Clicked(gtx) {
		d.wipe()
		onDone(restoreBackupResult{cancel: true})
		return layout.Dimensions{Size: gtx.Constraints.Max}
	}
	if d.restoreB.Clicked(gtx) {
		path := d.pathEd.Text()
		if path == "" {
			d.errorMsg = i18n.T("msg_empty_backup_path")
		} else {
			pw := []byte(d.pwEd.Text())
			cfg, err := config.LoadYAML(path, pw)
			for i := range pw {
				pw[i] = 0
			}
			switch {
			case errors.Is(err, config.ErrPasswordRequired):
				d.errorMsg = i18n.T("msg_password_required")
			case errors.Is(err, config.ErrPasswordWrong):
				d.errorMsg = i18n.T("msg_password_wrong")
			case err != nil:
				d.errorMsg = fmt.Sprintf(i18n.T("msg_restore_failed"), err.Error())
				global.Log.WithField("func", "internal.ui.restoreBackupDialog.Layout").
					WithError(err).Warn("restore backup failed")
			default:
				d.wipe()
				onDone(restoreBackupResult{cfg: cfg})
				return layout.Dimensions{Size: gtx.Constraints.Max}
			}
		}
	}

	body := func(gtx layout.Context) layout.Dimensions {
		return layout.Flex{Axis: layout.Vertical}.Layout(gtx,
			layout.Rigid(material.Body2(th, i18n.T("restore_backup_intro")).Layout),
			layout.Rigid(layout.Spacer{Height: 8}.Layout),
			layout.Rigid(labeledEditor(th, i18n.T("label_backup_path"), &d.pathEd, "backup.winauth.bak")),
			layout.Rigid(labeledEditor(th, i18n.T("label_password"), &d.pwEd, "")),
			layout.Rigid(errorLabel(th, d.errorMsg)),
		)
	}
	return modalCard(gtx, th, i18n.T("dialog_restore_backup_title"),
		i18n.T("btn_restore"), i18n.T("btn_cancel"),
		&d.restoreB, &d.cancelB, body)
}

func (d *restoreBackupDialog) wipe() {
	d.pwEd.SetText("")
}