package ui

import (
	"context"
	"fmt"
	"strings"
	"sync"
	"time"

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

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

// restoreBattleNetDialog drives the paper-restore flow: the user types
// the serial they wrote down at enrollment time plus the 10-char
// restore code, and the backend asks Blizzard for the original secret.
//
// SECURITY: the restore code is functionally a root key — anybody
// holding it can recover the authenticator and authorize Battle.Net
// logins. The editor masks it by default and we never log it.
type restoreBattleNetDialog struct {
	nameEd    widget.Editor
	serialEd  widget.Editor
	codeEd    widget.Editor
	showCode  widget.Bool
	okBtn     widget.Clickable
	cancelBtn widget.Clickable
	errorMsg  string

	mu       sync.Mutex
	pending  bool
	result   *authenticator.BattleNetAuthenticator
	resultEr error

	invalidate func()
}

func newRestoreBattleNetDialog(invalidate func()) *restoreBattleNetDialog {
	d := &restoreBattleNetDialog{invalidate: invalidate}
	d.nameEd.SingleLine = true
	d.serialEd.SingleLine = true
	d.codeEd.SingleLine = true
	d.codeEd.Mask = '*'
	return d
}

func (d *restoreBattleNetDialog) Layout(
	gtx layout.Context, th *material.Theme,
	onDone func(authenticator.Authenticator, string),
) layout.Dimensions {
	const fn = "internal.ui.restoreBattleNetDialog.Layout"

	if d.showCode.Update(gtx) {
		if d.showCode.Value {
			d.codeEd.Mask = 0
		} else {
			d.codeEd.Mask = '*'
		}
	}

	d.mu.Lock()
	pending := d.pending
	finished := !pending && (d.result != nil || d.resultEr != nil)
	res := d.result
	resErr := d.resultEr
	d.mu.Unlock()

	if finished {
		if resErr != nil {
			d.errorMsg = fmt.Sprintf(i18n.T("msg_restore_failed"), resErr.Error())
			d.mu.Lock()
			d.result, d.resultEr = nil, nil
			d.mu.Unlock()
		} else if res != nil {
			name := strings.TrimSpace(d.nameEd.Text())
			if name == "" {
				name = i18n.T("vendor_battlenet")
			}
			// Wipe the code editor so a leftover value cannot be read
			// off the screen if the parent reuses the dialog.
			d.codeEd.SetText("")
			onDone(res, name)
			return layout.Dimensions{Size: gtx.Constraints.Max}
		}
	}

	if d.okBtn.Clicked(gtx) && !pending {
		serial := strings.TrimSpace(d.serialEd.Text())
		code := d.codeEd.Text()
		if serial == "" {
			d.errorMsg = i18n.T("msg_empty_serial")
		} else if strings.TrimSpace(code) == "" {
			d.errorMsg = i18n.T("msg_empty_restore_code")
		} else {
			d.mu.Lock()
			d.pending = true
			d.errorMsg = i18n.T("msg_restoring")
			d.mu.Unlock()
			go func(serial, code string) {
				ctx, cancel := context.WithTimeout(context.Background(), 30*time.Second)
				defer cancel()
				b := authenticator.NewBattleNetAuthenticator()
				err := b.Restore(ctx, serial, code)
				d.mu.Lock()
				d.pending = false
				if err != nil {
					global.Log.WithField("func", fn).WithError(err).Warn("battle.net restore failed")
					d.resultEr = err
				} else {
					d.result = b
				}
				d.mu.Unlock()
				if d.invalidate != nil {
					d.invalidate()
				}
			}(serial, code)
		}
	}
	if d.cancelBtn.Clicked(gtx) && !pending {
		// Clear the code editor on cancel so the secret does not linger.
		d.codeEd.SetText("")
		onDone(nil, "")
		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("battlenet_restore_intro")).Layout),
			layout.Rigid(layout.Spacer{Height: unit.Dp(8)}.Layout),
			layout.Rigid(labeledEditor(th, i18n.T("label_name"), &d.nameEd, i18n.T("vendor_battlenet"))),
			layout.Rigid(labeledEditor(th, i18n.T("label_serial"), &d.serialEd, "US-1234-5678-9012")),
			layout.Rigid(labeledEditor(th, i18n.T("label_restore_code"), &d.codeEd, "")),
			layout.Rigid(material.CheckBox(th, &d.showCode, i18n.T("label_show_restore_code")).Layout),
			layout.Rigid(errorLabel(th, d.errorMsg)),
		)
	}
	return modalCard(gtx, th, i18n.T("dialog_restore_battlenet_title"),
		i18n.T("btn_restore"), i18n.T("btn_cancel"),
		&d.okBtn, &d.cancelBtn, body)
}