package main

import (
	"bytes"
	"image"
	"image/color"
	"image/png"

	"github.com/getlantern/systray"
	"github.com/wailsapp/wails/v2/pkg/runtime"
)

// Precomputed tray icons
var (
	iconGray   = makeVpnIcon(130, 130, 130)
	iconGreen  = makeVpnIcon(76, 175, 80)
	iconYellow = makeVpnIcon(253, 216, 53)
	iconRed    = makeVpnIcon(229, 57, 53)
)

func makeVpnIcon(r, g, b uint8) []byte {
	const size = 16
	img := image.NewNRGBA(image.Rect(0, 0, size, size))
	bg := color.NRGBA{R: r, G: g, B: b, A: 255}

	type pt struct{ x, y int }
	skip := make(map[pt]bool)

	// Make a horizontal pill-shaped rectangle
	// Skip rows 0, 1, 14, 15
	for x := 0; x < size; x++ {
		skip[pt{x, 0}] = true; skip[pt{x, 1}] = true
		skip[pt{x, 14}] = true; skip[pt{x, 15}] = true
	}
	// Round corners of the remaining rectangle (rows 2-13)
	// y=2 and y=13 skip x=0,1, 14,15
	skip[pt{0, 2}] = true; skip[pt{1, 2}] = true; skip[pt{14, 2}] = true; skip[pt{15, 2}] = true
	skip[pt{0, 13}] = true; skip[pt{1, 13}] = true; skip[pt{14, 13}] = true; skip[pt{15, 13}] = true
	// y=3 and y=12 skip x=0, 15
	skip[pt{0, 3}] = true; skip[pt{15, 3}] = true
	skip[pt{0, 12}] = true; skip[pt{15, 12}] = true

	// Draw rounded background
	for y := 0; y < size; y++ {
		for x := 0; x < size; x++ {
			if !skip[pt{x, y}] {
				img.SetNRGBA(x, y, bg)
			}
		}
	}

	// Draw "VPN" text in white using pixel font
	white := color.NRGBA{255, 255, 255, 255}
	// V (x: 2-4, y: 5-9)
	img.SetNRGBA(2, 5, white); img.SetNRGBA(4, 5, white)
	img.SetNRGBA(2, 6, white); img.SetNRGBA(4, 6, white)
	img.SetNRGBA(2, 7, white); img.SetNRGBA(4, 7, white)
	img.SetNRGBA(3, 8, white); img.SetNRGBA(3, 9, white)

	// P (x: 6-8, y: 5-9)
	for y := 5; y <= 9; y++ { img.SetNRGBA(6, y, white) }
	img.SetNRGBA(7, 5, white); img.SetNRGBA(8, 5, white)
	img.SetNRGBA(8, 6, white)
	img.SetNRGBA(7, 7, white); img.SetNRGBA(8, 7, white)

	// N (x: 10-13, y: 5-9)
	for y := 5; y <= 9; y++ { img.SetNRGBA(10, y, white); img.SetNRGBA(13, y, white) }
	img.SetNRGBA(11, 6, white)
	img.SetNRGBA(11, 7, white); img.SetNRGBA(12, 7, white)
	img.SetNRGBA(12, 8, white)

	var buf bytes.Buffer
	_ = png.Encode(&buf, img)

	// Wrap PNG in ICO format
	pngData := buf.Bytes()
	var ico bytes.Buffer
	ico.Write([]byte{0, 0, 1, 0, 1, 0}) // ICONDIR
	ico.Write([]byte{16, 16, 0, 0, 1, 0, 32, 0}) // ICONDIRENTRY (16x16, 32bpp)
	sizeBytes := len(pngData)
	ico.WriteByte(byte(sizeBytes & 0xFF))
	ico.WriteByte(byte((sizeBytes >> 8) & 0xFF))
	ico.WriteByte(byte((sizeBytes >> 16) & 0xFF))
	ico.WriteByte(byte((sizeBytes >> 24) & 0xFF))
	ico.Write([]byte{22, 0, 0, 0}) // Image offset
	ico.Write(pngData)

	return ico.Bytes()
}

func (a *App) setupTray() {
	go systray.Run(a.onTrayReady, func() {})
}

func (a *App) onTrayReady() {
	systray.SetIcon(iconGray)
	systray.SetTooltip("kettuRay — Disconnected")

	mToggle := systray.AddMenuItem("Connect", "Toggle VPN")
	systray.AddSeparator()
	mShow := systray.AddMenuItem("Show", "Show window")
	systray.AddSeparator()
	mQuit := systray.AddMenuItem("Exit", "Exit kettuRay")

	// Store menu item reference for text updates
	a.mu.Lock()
	a.trayToggleItem = mToggle
	a.mu.Unlock()

	go func() {
		for {
			select {
			case <-mToggle.ClickedCh:
				a.toggleVPN()
			case <-mShow.ClickedCh:
				runtime.WindowShow(a.ctx)
			case <-mQuit.ClickedCh:
				runtime.Quit(a.ctx)
			}
		}
	}()
}

func (a *App) updateTrayState(state string) {
	switch state {
	case "Connected":
		systray.SetIcon(iconGreen)
		systray.SetTooltip("kettuRay — Connected")
		a.mu.Lock()
		if a.trayToggleItem != nil {
			a.trayToggleItem.SetTitle("Disconnect")
		}
		a.mu.Unlock()
	case "Connecting":
		systray.SetIcon(iconYellow)
		systray.SetTooltip("kettuRay — Connecting...")
		a.mu.Lock()
		if a.trayToggleItem != nil {
			a.trayToggleItem.SetTitle("Connecting...")
		}
		a.mu.Unlock()
	case "Disconnecting":
		systray.SetIcon(iconYellow)
		systray.SetTooltip("kettuRay — Disconnecting...")
	case "Error":
		systray.SetIcon(iconRed)
		systray.SetTooltip("kettuRay — Error")
		a.mu.Lock()
		if a.trayToggleItem != nil {
			a.trayToggleItem.SetTitle("Connect")
		}
		a.mu.Unlock()
	default: // Disconnected
		systray.SetIcon(iconGray)
		systray.SetTooltip("kettuRay — Disconnected")
		a.mu.Lock()
		if a.trayToggleItem != nil {
			a.trayToggleItem.SetTitle("Connect")
		}
		a.mu.Unlock()
	}
}

func (a *App) toggleVPN() {
	a.mu.Lock()
	state := a.manager.State
	id := a.selectedConfigID
	a.mu.Unlock()

	switch state {
	case 2: // Connected
		go a.manager.Disconnect()
	case 1: // Connecting
		go a.manager.Disconnect()
	default:
		if id != "" {
			go a.connectByID(id)
		}
	}
}

// HideWindow hides the app window (minimize to tray).
func (a *App) HideWindow() {
	runtime.WindowHide(a.ctx)
}