package ui

import (
	"fmt"
	"image/color"
	"log"
	"strings"

	"github.com/0x1d/rcond/pkg/config"
	tea "github.com/charmbracelet/bubbletea"
	"github.com/charmbracelet/huh"
	"github.com/charmbracelet/lipgloss"
	"github.com/skip2/go-qrcode"
)

const maxWidth = 120

type UI struct {
	appConfig *config.Config
	program   *tea.Program
}

type UIConfig struct {
	Enabled bool `yaml:"enabled" envconfig:"UI_ENABLED"`
}

var (
	red    = lipgloss.AdaptiveColor{Light: "#FE5F86", Dark: "#FE5F86"}
	indigo = lipgloss.AdaptiveColor{Light: "#5A56E0", Dark: "#7571F9"}
	green  = lipgloss.AdaptiveColor{Light: "#02BA84", Dark: "#02BF87"}
)

type Styles struct {
	Base,
	HeaderText,
	Status,
	StatusHeader,
	Highlight,
	ErrorHeaderText,
	Help lipgloss.Style
}

func NewStyles(lg *lipgloss.Renderer) *Styles {
	s := Styles{}
	s.Base = lg.NewStyle().
		Padding(1, 4, 0, 1)
	s.HeaderText = lg.NewStyle().
		Foreground(indigo).
		Bold(true).
		Padding(0, 1, 0, 2)
	s.Status = lg.NewStyle().
		Border(lipgloss.RoundedBorder()).
		BorderForeground(indigo).
		PaddingLeft(1).
		MarginTop(1)
	s.StatusHeader = lg.NewStyle().
		Foreground(green).
		Bold(true)
	s.Highlight = lg.NewStyle().
		Foreground(lipgloss.Color("212"))
	s.ErrorHeaderText = s.HeaderText.
		Foreground(red)
	s.Help = lg.NewStyle().
		Foreground(lipgloss.Color("240"))
	return &s
}

type state int

const (
	statusNormal state = iota
	stateModeSelection
	stateDone
)

type Model struct {
	state     state
	lg        *lipgloss.Renderer
	styles    *Styles
	form      *huh.Form
	width     int
	appConfig *config.Config
}

func NewModel(appConfig *config.Config) Model {
	m := Model{width: maxWidth, state: stateModeSelection, appConfig: appConfig}
	m.lg = lipgloss.DefaultRenderer()
	m.styles = NewStyles(m.lg)

	m.form = m.createModeForm()

	return m
}

func (m Model) createModeForm() *huh.Form {
	return huh.NewForm(
		huh.NewGroup(
			huh.NewSelect[string]().
				Key("mode").
				Options(huh.NewOptions("AP", "STA")...).
				Title("Parameters").
				Description("What do you want to configure?"),
		),
	).
		WithWidth(45).
		WithShowHelp(false).
		WithShowErrors(false)
}

func min(x, y int) int {
	if x > y {
		return y
	}
	return x
}

func (m Model) Init() tea.Cmd {
	return m.form.Init()
}
func (m Model) Update(msg tea.Msg) (tea.Model, tea.Cmd) {
	switch msg := msg.(type) {
	case tea.WindowSizeMsg:
		m.width = min(msg.Width, maxWidth) - m.styles.Base.GetHorizontalFrameSize()
	case tea.KeyMsg:
		switch msg.String() {
		case "ctrl+c":
			return m, tea.Interrupt
		case "esc", "q":
			return m, tea.Quit
		}
	}

	var cmds []tea.Cmd

	// Process the form
	form, cmd := m.form.Update(msg)
	if f, ok := form.(*huh.Form); ok {
		m.form = f
		cmds = append(cmds, cmd)
	}

	// Handle mode selection
	if m.state == stateModeSelection && m.form.State == huh.StateCompleted {
		mode := m.form.GetString("mode")
		if mode == "AP" {
			m.form = m.createAPForm()
			m.state = statusNormal
			return m, m.form.Init()
		} else if mode == "STA" {
			m.form = m.createSTAForm()
			m.state = statusNormal
			return m, m.form.Init()
		}
	}

	// After form completion, show mode selection again
	if m.state == statusNormal && m.form.State == huh.StateCompleted {
		m.appConfig.Wifi.AP.SSID = m.form.GetString("ssid")
		m.appConfig.Wifi.AP.Password = m.form.GetString("password")
		m.appConfig.Wifi.AP.Encryption = m.form.GetString("encryption")

		m.form = m.createModeForm()
		m.state = stateModeSelection
		return m, m.form.Init()
	}

	return m, tea.Batch(cmds...)
}

func (m Model) createAPForm() *huh.Form {
	if m.appConfig == nil {
		log.Fatal("appConfig is nil")
		return nil // or handle the error appropriately
	}
	return huh.NewForm(
		huh.NewGroup(
			huh.NewInput().
				Key("ssid").
				Placeholder("Access Point SSID").
				Title("SSID").
				Description("The name of your access point").
				Value(&m.appConfig.Wifi.AP.SSID),

			huh.NewInput().
				Key("password").
				Placeholder("Access Point Password").
				Title("Password").
				EchoMode(huh.EchoModePassword).
				Description("The password for your access point").
				Validate(func(v string) error {
					if len(v) < 8 {
						return fmt.Errorf("password must be at least 8 characters long")
					}
					return nil
				}).
				Value(&m.appConfig.Wifi.AP.Password),

			huh.NewSelect[string]().
				Key("encryption").
				Options(huh.NewOptions("WPA2", "WPA3", "WEP")...).
				Title("Encryption").
				Description("The encryption method for your access point").
				Value(&m.appConfig.Wifi.AP.Encryption),

			huh.NewConfirm().
				Key("save").
				Title("Apply configuration").
				Validate(func(v bool) error {
					if !v {
						m.state = stateModeSelection
						return nil
					}
					return nil
				}).
				Affirmative("Yep").
				Negative("Nope"),
		),
	).
		WithWidth(45).
		WithShowHelp(false).
		WithShowErrors(false)
}

func (m Model) createSTAForm() *huh.Form {
	return huh.NewForm(
		huh.NewGroup(
			huh.NewInput().
				Key("ssid").
				Placeholder("Station SSID").
				Title("SSID").
				Description("The name of the station").
				Value(&m.appConfig.Wifi.STA.SSID),

			huh.NewInput().
				Key("password").
				Placeholder("Station Password").
				Title("Password").
				EchoMode(huh.EchoModePassword).
				Description("The password for the station").
				Validate(func(v string) error {
					if len(v) < 8 {
						return fmt.Errorf("password must be at least 8 characters long")
					}
					return nil
				}).
				Value(&m.appConfig.Wifi.STA.Password),
			huh.NewConfirm().
				Key("done").
				Title("All done?").
				Validate(func(v bool) error {
					if !v {
						return fmt.Errorf("Welp, finish up then")
					}
					return nil
				}).
				Affirmative("Yep").
				Negative("Wait, no"),
		),
	).
		WithWidth(45).
		WithShowHelp(false).
		WithShowErrors(false)
}

func (m Model) View() string {
	s := m.styles

	switch m.state {
	case stateModeSelection:
		v := strings.TrimSuffix(m.form.View(), "\n\n")
		form := m.lg.NewStyle().Margin(1, 0).Render(v)
		header := m.appBoundaryView("Configuration")
		footer := m.appBoundaryView(m.form.Help().ShortHelpView(m.form.KeyBinds()))
		return s.Base.Render(header + "\n" + form + "\n\n" + footer)
	case statusNormal:
		switch m.form.State {
		case huh.StateCompleted:
			ssid := m.appConfig.Wifi.STA.SSID
			password := m.appConfig.Wifi.STA.Password
			encryption := m.appConfig.Wifi.STA.Encryption
			qrCode, err := qrcode.New("WIFI:S:"+ssid+";T:"+encryption+";P:"+password+";;", qrcode.Medium)
			if err != nil {
				log.Fatal(err)
			}
			qrCode.DisableBorder = true
			qrCodeImage := qrCode.ToSmallString(false)

			var b strings.Builder
			fmt.Fprintf(&b, "Congratulations, you've configured your access point!\n\n")
			fmt.Fprintf(&b, "SSID: %s\nEncryption: %s\n\nPlease proceed to connect to your access point.\n\n", ssid, encryption)

			// Center the QR code
			centeredQRCode := lipgloss.NewStyle().Render(qrCodeImage)
			b.WriteString(centeredQRCode)

			return s.Status.Margin(0, 1).Padding(2, 2).Width(48).Render(b.String()) + "\n\n"
		default:
			var ssid string
			var newSsid, newPassword, newEncryption string
			var encryption string
			var password string
			var qrCodeImage string
			ssid = m.appConfig.Wifi.STA.SSID
			password = m.appConfig.Wifi.STA.Password
			encryption = m.appConfig.Wifi.STA.Encryption

			newSsid = m.form.GetString("ssid")
			if ssid != newSsid && newSsid != "" {
				ssid = newSsid
			}
			newPassword = m.form.GetString("password")
			if password != newPassword && newPassword != "" {
				password = newPassword
			}
			newEncryption = m.form.GetString("encryption")
			if encryption != newEncryption && newEncryption != "" {
				encryption = newEncryption
			}

			if ssid != "" && password != "" && encryption != "" {
				qrCode, err := qrcode.New("WIFI:S:"+ssid+";T:"+encryption+";P:"+password+";;", qrcode.Medium)
				qrCode.BackgroundColor = color.White
				qrCode.DisableBorder = false
				if err != nil {
					log.Fatal(err)
				}
				qrCodeImage = qrCode.ToSmallString(false)
			}

			// Form (left side)
			v := strings.TrimSuffix(m.form.View(), "\n\n")
			form := m.lg.NewStyle().Margin(1, 0).Render(v)

			// Status (right side)
			var status string
			{
				var (
					buildInfo = "(None)"
				)

				if ssid != "" {
					buildInfo = "SSID: " + ssid
				}
				if password != "" {
					buildInfo += "\n" + "Password: " + strings.Repeat("*", len(password))
				}
				if encryption != "" {
					buildInfo += "\n" + "Encryption: " + encryption
				}

				if qrCodeImage != "" {
					buildInfo += "\n\n" + qrCodeImage
				}

				const statusWidth = 50
				statusMarginLeft := m.width - statusWidth - lipgloss.Width(form) - s.Status.GetMarginRight()
				status = s.Status.
					Height(lipgloss.Height(form)).
					Width(statusWidth).
					MarginLeft(statusMarginLeft).
					Render(s.StatusHeader.Render("Current Configuration") + "\n" +
						buildInfo)
			}

			errors := m.form.Errors()
			header := m.appBoundaryView("Node Configuration")
			if len(errors) > 0 {
				header = m.appErrorBoundaryView(m.errorView())
			}
			body := lipgloss.JoinHorizontal(lipgloss.Left, form, status)

			footer := m.appBoundaryView(m.form.Help().ShortHelpView(m.form.KeyBinds()))
			if len(errors) > 0 {
				footer = m.appErrorBoundaryView("")
			}

			return s.Base.Render(header + "\n" + body + "\n\n" + footer)
		}
	}

	return ""
}

func (m Model) errorView() string {
	var s string
	for _, err := range m.form.Errors() {
		s += err.Error()
	}
	return s
}

func (m Model) appBoundaryView(text string) string {
	return lipgloss.PlaceHorizontal(
		m.width,
		lipgloss.Left,
		m.styles.HeaderText.Render(text),
		lipgloss.WithWhitespaceChars("/"),
		lipgloss.WithWhitespaceForeground(indigo),
	)
}

func (m Model) appErrorBoundaryView(text string) string {
	return lipgloss.PlaceHorizontal(
		m.width,
		lipgloss.Left,
		m.styles.ErrorHeaderText.Render(text),
		lipgloss.WithWhitespaceChars("/"),
		lipgloss.WithWhitespaceForeground(red),
	)
}

func NewUI(appConfig *config.Config) *UI {
	// Initialize our program
	ui := &UI{appConfig: appConfig}
	fmt.Printf("SSID: %s", appConfig.Wifi.AP.SSID)
	ui.program = tea.NewProgram(NewModel(appConfig), tea.WithAltScreen())
	if _, err := ui.program.Run(); err != nil {
		log.Fatal(err)
	}
	return ui
}