package main

import (
	"encoding/base64"
	"fmt"
	"os"

	"golang.design/x/clipboard"

	"github.com/charmbracelet/bubbles/help"
	"github.com/charmbracelet/bubbles/key"
	"github.com/charmbracelet/bubbles/textarea"
	tea "github.com/charmbracelet/bubbletea"
	"github.com/charmbracelet/lipgloss"
)

var (
	cursorStyle = lipgloss.NewStyle().Foreground(lipgloss.Color("212"))

	cursorLineStyle = lipgloss.NewStyle().
			Background(lipgloss.Color("57")).
			Foreground(lipgloss.Color("230"))

	placeholderStyle = lipgloss.NewStyle().
				Foreground(lipgloss.Color("238"))

	endOfBufferStyle = lipgloss.NewStyle().
				Foreground(lipgloss.Color("235"))

	focusedPlaceholderStyle = lipgloss.NewStyle().
				Foreground(lipgloss.Color("99"))

	focusedBorderStyle = lipgloss.NewStyle().
				Border(lipgloss.RoundedBorder()).
				BorderForeground(lipgloss.Color("238"))

	blurredBorderStyle = lipgloss.NewStyle().
				Border(lipgloss.HiddenBorder())
)

type keymap = struct {
	next, copy, clear, quit key.Binding
}

func newTextarea() textarea.Model {
	t := textarea.New()
	t.Prompt = ""
	t.Placeholder = "Type something"
	t.ShowLineNumbers = true
	t.Cursor.Style = cursorStyle
	t.FocusedStyle.Placeholder = focusedPlaceholderStyle
	t.BlurredStyle.Placeholder = placeholderStyle
	t.FocusedStyle.CursorLine = cursorLineStyle
	t.FocusedStyle.Base = focusedBorderStyle
	t.BlurredStyle.Base = blurredBorderStyle
	t.FocusedStyle.EndOfBuffer = endOfBufferStyle
	t.BlurredStyle.EndOfBuffer = endOfBufferStyle
	t.KeyMap.DeleteWordBackward.SetEnabled(false)
	t.KeyMap.LineNext = key.NewBinding(key.WithKeys("down"))
	t.KeyMap.LinePrevious = key.NewBinding(key.WithKeys("up"))
	t.CharLimit = (1024 * 8) * 8
	t.MaxHeight = 1024 * 8
	t.Blur()
	return t
}

type model struct {
	width   int
	height  int
	keymap  keymap
	help    help.Model
	decoded textarea.Model
	encoded textarea.Model
}

func newModel() model {
	m := model{
		encoded: newTextarea(),
		decoded: newTextarea(),
		help:    help.New(),
		keymap: keymap{
			next: key.NewBinding(
				key.WithKeys("tab"),
				key.WithHelp("tab", "next"),
			),
			quit: key.NewBinding(
				key.WithKeys("esc", "ctrl+c"),
				key.WithHelp("esc", "quit"),
			),
			copy: key.NewBinding(
				key.WithKeys("ctrl+x"),
			),
			clear: key.NewBinding(
				key.WithKeys("ctrl+r"),
			),
		},
	}
	m.decoded.Focus()
	return m
}

func (m model) Init() tea.Cmd {
	return textarea.Blink
}

func (m model) Update(msg tea.Msg) (tea.Model, tea.Cmd) {
	var cmds []tea.Cmd

	switch msg := msg.(type) {
	case tea.KeyMsg:
		switch {
		case key.Matches(msg, m.keymap.quit):
			m.encoded.Blur()
			m.decoded.Blur()
			return m, tea.Quit
		case key.Matches(msg, m.keymap.next):
			if m.encoded.Focused() {
				cmds = append(cmds, m.decoded.Focus())
				m.encoded.Blur()
			} else if m.decoded.Focused() {
				cmds = append(cmds, m.encoded.Focus())
				m.decoded.Blur()
			}
		case key.Matches(msg, m.keymap.copy):
			if m.encoded.Focused() {
				clipboard.Write(clipboard.FmtText, []byte(m.encoded.Value()))
			} else if m.decoded.Focused() {
				clipboard.Write(clipboard.FmtText, []byte(m.decoded.Value()))
			}
		case key.Matches(msg, m.keymap.clear):
			m.encoded.SetValue("")
			m.decoded.SetValue("")
		}
	case tea.WindowSizeMsg:
		m.height = msg.Height
		m.width = msg.Width
	}

	m.sizeInputs()

	if m.encoded.Focused() {
		decoded, err := base64.StdEncoding.DecodeString(m.encoded.Value())
		if err != nil {
			// log.Printf("failed to decode: %v", err)
		} else {
			m.decoded.SetValue(string(decoded))
		}
	} else if m.decoded.Focused() {
		encoded := base64.StdEncoding.EncodeToString([]byte(m.decoded.Value()))
		m.encoded.SetValue(string(encoded))
	}

	encoded, cmd := m.encoded.Update(msg)
	cmds = append(cmds, cmd)
	m.encoded = encoded

	decoded, cmd := m.decoded.Update(msg)
	cmds = append(cmds, cmd)
	m.decoded = decoded

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

func (m *model) sizeInputs() {
	m.encoded.SetHeight(m.height - 5)
	m.decoded.SetHeight(m.height - 5)
	m.encoded.SetWidth(m.width/2 - 5)
	m.decoded.SetWidth(m.width/2 - 5)
}

func (m model) View() string {
	help := m.help.ShortHelpView([]key.Binding{
		m.keymap.next,
		m.keymap.copy,
		m.keymap.quit,
	})

	var views []string
	views = append(views, m.decoded.View())
	views = append(views, m.encoded.View())

	return lipgloss.JoinHorizontal(lipgloss.Top, views...) + "\n" + help
}

func main() {
	clipboard.Init()
	if _, err := tea.NewProgram(newModel(), tea.WithAltScreen()).Run(); err != nil {
		fmt.Println("Error while running program:", err)
		os.Exit(1)
	}
}