//go:build kanholec_gui

package gui

import (
	"fmt"
	"io"
	"net/http"
	"strings"
	"sync"

	"fyne.io/fyne/v2"
	"fyne.io/fyne/v2/app"
	"fyne.io/fyne/v2/container"
	"fyne.io/fyne/v2/dialog"
	"fyne.io/fyne/v2/layout"
	"fyne.io/fyne/v2/theme"
	"fyne.io/fyne/v2/widget"

	"kanhole/pkg/config"
	v1 "kanhole/pkg/config/v1"
	"kanhole/pkg/util/log"
)

type App struct {
	fyneApp fyne.App
	window  fyne.Window

	serverURL  *widget.Entry
	authToken  *widget.Entry
	clientKey  *widget.Entry
	statusLabel *widget.Label
	configView *widget.Entry
	proxyList  *widget.List
	startBtn   *widget.Button
	stopBtn    *widget.Button
	connectBtn *widget.Button

	mu         sync.Mutex
	running    bool
	configData string
}

func New() *App {
	a := &App{}
	a.fyneApp = app.New()
	a.window = a.fyneApp.NewWindow("kanholec GUI")
	a.window.Resize(fyne.NewSize(850, 620))
	a.window.SetMaster()
	a.setupUI()
	return a
}

func (a *App) saveSettings() {
	p := a.fyneApp.Preferences()
	p.SetString("server_url", a.serverURL.Text)
}

func (a *App) loadSettings() {
	p := a.fyneApp.Preferences()
	if url := p.StringWithFallback("server_url", "http://localhost:7500"); url != "" {
		a.serverURL.SetText(url)
	}
}

func (a *App) setupUI() {
	a.serverURL = widget.NewEntry()
	a.serverURL.SetText("http://localhost:7500")
	a.serverURL.PlaceHolder = "http://frps-server:7500"

	a.authToken = widget.NewEntry()
	a.authToken.PlaceHolder = "One-time token"

	a.clientKey = widget.NewEntry()
	a.clientKey.PlaceHolder = "Client key (from server)"

	a.statusLabel = widget.NewLabel("Not connected")
	a.statusLabel.Importance = widget.MediumImportance

	a.configView = widget.NewMultiLineEntry()
	a.configView.SetMinRowsVisible(8)
	a.configView.Disable()

	a.proxyList = widget.NewList(
		func() int { return 0 },
		func() fyne.CanvasObject { return widget.NewLabel("") },
		func(id widget.ListItemID, o fyne.CanvasObject) {},
	)

	a.connectBtn = widget.NewButtonWithIcon("Connect", theme.NavigateNextIcon(), a.onConnect)
	a.startBtn = widget.NewButtonWithIcon("Start", theme.MediaPlayIcon(), a.onStart)
	a.startBtn.Disable()
	a.stopBtn = widget.NewButtonWithIcon("Stop", theme.MediaStopIcon(), a.onStop)
	a.stopBtn.Disable()

	// Settings form
	settingsForm := widget.NewForm(
		widget.NewFormItem("Server URL", a.serverURL),
	)
	settingsForm.OnSubmit = func() { a.saveSettings() }
	settingsBtn := widget.NewButtonWithIcon("Save Settings", theme.DocumentSaveIcon(), a.saveSettings)

	settingsTab := container.NewVBox(
		widget.NewLabelWithStyle("Connection Settings", fyne.TextAlignLeading, fyne.TextStyle{Bold: true}),
		settingsForm,
		settingsBtn,
		layout.NewSpacer(),
	)

	// Auth form
	authForm := widget.NewForm(
		widget.NewFormItem("Server URL", a.serverURL),
		widget.NewFormItem("One-Time Token", a.authToken),
		widget.NewFormItem("Client Key", a.clientKey),
	)

	statusLine := container.NewHBox(
		widget.NewLabelWithStyle("Status:", fyne.TextAlignLeading, fyne.TextStyle{Bold: true}),
		a.statusLabel,
		layout.NewSpacer(),
		a.connectBtn,
	)

	controls := container.NewHBox(
		a.startBtn,
		a.stopBtn,
	)

	connectTab := container.NewVBox(
		widget.NewLabelWithStyle("frp Client GUI", fyne.TextAlignCenter, fyne.TextStyle{Bold: true}),
		authForm,
		statusLine,
		controls,
		container.NewBorder(
			widget.NewLabelWithStyle("Proxies", fyne.TextAlignLeading, fyne.TextStyle{Bold: true}),
			nil, nil, nil,
			a.proxyList,
		),
	)

	// Config tab
	configTab := container.NewBorder(
		widget.NewLabelWithStyle("Configuration (read-only)", fyne.TextAlignLeading, fyne.TextStyle{Bold: true}),
		nil, nil, nil,
		a.configView,
	)

	tabs := container.NewAppTabs(
		container.NewTabItemWithIcon("Connect", theme.ComputerIcon(), connectTab),
		container.NewTabItemWithIcon("Config", theme.DocumentIcon(), configTab),
		container.NewTabItemWithIcon("Settings", theme.SettingsIcon(), settingsTab),
	)
	tabs.SelectIndex(0)

	a.window.SetContent(tabs)
	a.loadSettings()
}

func (a *App) onConnect() {
	url := strings.TrimRight(a.serverURL.Text, "/")
	token := a.authToken.Text
	key := a.clientKey.Text
	a.saveSettings()

	if token == "" && key == "" {
		a.statusLabel.SetText("Error: provide token or client key")
		return
	}

	if token != "" {
		apiURL := url + "/admin/api/client/auth"
		body := fmt.Sprintf(`{"token":"%s"}`, token)
		resp, err := http.Post(apiURL, "application/json", strings.NewReader(body))
		if err != nil {
			a.statusLabel.SetText(fmt.Sprintf("Error: %v", err))
			return
		}
		defer resp.Body.Close()

		if resp.StatusCode != http.StatusOK {
			respBody, _ := io.ReadAll(resp.Body)
			a.statusLabel.SetText(fmt.Sprintf("Auth failed (%d): %s", resp.StatusCode, string(respBody)))
			return
		}

		configData, _ := io.ReadAll(resp.Body)
		a.configData = string(configData)
		a.configView.SetText(a.configData)
		a.statusLabel.SetText("Connected (token auth)")
		a.startBtn.Enable()
		a.connectBtn.SetText("Reconnect")
	} else if key != "" {
		apiURL := fmt.Sprintf("%s/admin/api/frpc/proxy-config/%s", url, key)
		resp, err := http.Get(apiURL)
		if err != nil {
			a.statusLabel.SetText(fmt.Sprintf("Error: %v", err))
			return
		}
		defer resp.Body.Close()

		if resp.StatusCode != http.StatusOK {
			a.statusLabel.SetText(fmt.Sprintf("Config fetch failed (%d)", resp.StatusCode))
			return
		}

		configData, _ := io.ReadAll(resp.Body)
		a.configData = string(configData)
		a.configView.SetText(a.configData)
		a.statusLabel.SetText("Connected (key auth)")
		a.startBtn.Enable()
		a.connectBtn.SetText("Reconnect")
	}
}

func (a *App) onStart() {
	if a.configData == "" {
		a.statusLabel.SetText("Error: no config loaded")
		return
	}

	var cfg v1.ClientConfig
	if err := config.LoadConfigure([]byte(a.configData), &cfg, false, "toml"); err != nil {
		dialog.ShowError(fmt.Errorf("invalid config: %w", err), a.window)
		return
	}

	a.mu.Lock()
	a.running = true
	a.mu.Unlock()

	a.startBtn.Disable()
	a.stopBtn.Enable()
	a.statusLabel.SetText("Running")
}

func (a *App) onStop() {
	a.mu.Lock()
	a.running = false
	a.mu.Unlock()

	a.startBtn.Enable()
	a.stopBtn.Disable()
	a.statusLabel.SetText("Stopped")
}

func (a *App) Run() {
	a.window.ShowAndRun()
}

func Run() {
	gui := New()
	log.Infof("starting frpc GUI")
	gui.Run()
}