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"
)

// importLegacyDialog drives the "Import legacy WinAuth XML..." flow.
// It is intentionally minimal: a path field, an optional password field
// for entries the user encrypted in the original C# WinAuth, and Import
// + Cancel buttons. DPAPI-encrypted entries decrypt transparently on
// Windows; on other platforms they are skipped with a warning in the
// log.
type importLegacyDialog struct {
	pathEd   widget.Editor
	pwEd     widget.Editor
	importBt widget.Clickable
	cancelBt widget.Clickable

	errorMsg string
}

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

// importLegacyResult is what the dialog reports to its caller.
type importLegacyResult struct {
	cfg    *config.Config
	cancel bool
}

// Layout returns dimensions and reports outcomes via onDone. onDone is
// called with cancel=true on Cancel and with a non-nil cfg on success;
// validation errors are kept inside the dialog so the user can retry.
func (d *importLegacyDialog) Layout(
	gtx layout.Context, th *material.Theme,
	onDone func(importLegacyResult),
) layout.Dimensions {
	if d.cancelBt.Clicked(gtx) {
		d.wipe()
		onDone(importLegacyResult{cancel: true})
		return layout.Dimensions{Size: gtx.Constraints.Max}
	}
	if d.importBt.Clicked(gtx) {
		path := d.pathEd.Text()
		if path == "" {
			d.errorMsg = i18n.T("msg_empty_import_path")
		} else {
			password := []byte(d.pwEd.Text())
			cfg, err := config.LoadLegacyXML(path, password)
			for i := range password {
				password[i] = 0
			}
			switch {
			case errors.Is(err, config.ErrLegacyPasswordRequired):
				d.errorMsg = i18n.T("msg_legacy_password_required")
			case errors.Is(err, config.ErrLegacyPasswordWrong):
				d.errorMsg = i18n.T("msg_legacy_password_wrong")
			case err != nil:
				d.errorMsg = fmt.Sprintf(i18n.T("msg_import_failed"), err.Error())
				global.Log.WithField("func", "internal.ui.importLegacyDialog.Layout").
					WithError(err).Warn("legacy import failed")
			default:
				d.wipe()
				onDone(importLegacyResult{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("import_legacy_intro")).Layout),
			layout.Rigid(layout.Spacer{Height: 8}.Layout),
			layout.Rigid(labeledEditor(th, i18n.T("label_import_path"), &d.pathEd, "C:\\Users\\...\\winauth.xml")),
			layout.Rigid(labeledEditor(th, i18n.T("label_password"), &d.pwEd, "")),
			layout.Rigid(errorLabel(th, d.errorMsg)),
		)
	}
	return modalCard(gtx, th, i18n.T("dialog_import_legacy_title"),
		i18n.T("btn_import"), i18n.T("btn_cancel"),
		&d.importBt, &d.cancelBt, body)
}

// wipe clears the password editor so the plaintext bytes are not kept
// after the dialog closes.
func (d *importLegacyDialog) wipe() {
	d.pwEd.SetText("")
}