package main

import (
	"fmt"
	"io"
	"strings"

	"github.com/charmbracelet/bubbles/textinput"
	tea "github.com/charmbracelet/bubbletea"
	"github.com/charmbracelet/lipgloss"
)

type tuiTheme struct {
	outer          lipgloss.Style
	headerBar      lipgloss.Style
	badge          lipgloss.Style
	chrome         lipgloss.Style
	title          lipgloss.Style
	subtitle       lipgloss.Style
	sectionTitle   lipgloss.Style
	body           lipgloss.Style
	muted          lipgloss.Style
	footer         lipgloss.Style
	panel          lipgloss.Style
	panelAccent    lipgloss.Style
	row            lipgloss.Style
	rowSelected    lipgloss.Style
	rowNumber      lipgloss.Style
	rowNumberOn    lipgloss.Style
	rowKey         lipgloss.Style
	rowKeySelected lipgloss.Style
	rowTitle       lipgloss.Style
	rowTitleOn     lipgloss.Style
	rowHint        lipgloss.Style
	rowHintActive  lipgloss.Style
	statusInfo     lipgloss.Style
	statusWarn     lipgloss.Style
	statusSuccess  lipgloss.Style
	inputLabel     lipgloss.Style
	inputBox       lipgloss.Style
}

func newTUITheme() tuiTheme {
	border := lipgloss.Color("#5A6772")
	borderSoft := lipgloss.Color("#31414A")
	text := lipgloss.Color("#ECE4D8")
	muted := lipgloss.Color("#A49788")
	accent := lipgloss.Color("#D9733F")
	accentSoft := lipgloss.Color("#F2D2B5")
	panel := lipgloss.Color("#161C20")
	panelAlt := lipgloss.Color("#212A30")
	panelLift := lipgloss.Color("#2B363D")
	info := lipgloss.Color("#86B7C6")
	warn := lipgloss.Color("#D8AB63")
	success := lipgloss.Color("#91B57F")

	return tuiTheme{
		outer: lipgloss.NewStyle().
			Border(lipgloss.RoundedBorder()).
			BorderForeground(border).
			Padding(1, 2),
		headerBar: lipgloss.NewStyle().
			Foreground(borderSoft),
		chrome: lipgloss.NewStyle().
			Foreground(muted),
		badge: lipgloss.NewStyle().
			Foreground(panel).
			Background(accentSoft).
			Bold(true).
			Padding(0, 1),
		subtitle: lipgloss.NewStyle().
			Foreground(muted),
		title: lipgloss.NewStyle().
			Foreground(text).
			Bold(true),
		sectionTitle: lipgloss.NewStyle().
			Foreground(accentSoft).
			Bold(true).
			Border(lipgloss.NormalBorder(), false, false, true, false).
			BorderForeground(borderSoft).
			PaddingBottom(0).
			MarginBottom(1),
		body: lipgloss.NewStyle().
			Foreground(text),
		muted: lipgloss.NewStyle().
			Foreground(muted),
		footer: lipgloss.NewStyle().
			Foreground(muted).
			Border(lipgloss.NormalBorder(), true, false, false, false).
			BorderForeground(borderSoft).
			PaddingTop(1).
			MarginTop(1),
		panel: lipgloss.NewStyle().
			Border(lipgloss.NormalBorder(), false, false, false, true).
			BorderForeground(borderSoft).
			PaddingLeft(1).
			MarginBottom(1),
		panelAccent: lipgloss.NewStyle().
			Border(lipgloss.ThickBorder(), false, false, false, true).
			BorderForeground(accent).
			PaddingLeft(1).
			MarginBottom(1),
		row: lipgloss.NewStyle().
			Border(lipgloss.NormalBorder(), false, false, false, true).
			BorderForeground(panelLift).
			Padding(0, 1).
			MarginBottom(1),
		rowSelected: lipgloss.NewStyle().
			Border(lipgloss.ThickBorder(), false, false, false, true).
			BorderForeground(accent).
			Background(panel).
			Padding(0, 1).
			MarginBottom(1),
		rowNumber: lipgloss.NewStyle().
			Foreground(muted),
		rowNumberOn: lipgloss.NewStyle().
			Foreground(accentSoft).
			Bold(true),
		rowKey: lipgloss.NewStyle().
			Foreground(accent).
			Bold(true).
			Background(panelAlt).
			Padding(0, 1),
		rowKeySelected: lipgloss.NewStyle().
			Foreground(accentSoft).
			Background(panelLift).
			Bold(true).
			Padding(0, 1),
		rowTitle: lipgloss.NewStyle().
			Foreground(text).
			Bold(true),
		rowTitleOn: lipgloss.NewStyle().
			Foreground(text).
			Bold(true),
		rowHint: lipgloss.NewStyle().
			Foreground(muted),
		rowHintActive: lipgloss.NewStyle().
			Foreground(text),
		statusInfo: lipgloss.NewStyle().
			Foreground(info).
			Bold(true),
		statusWarn: lipgloss.NewStyle().
			Foreground(warn).
			Bold(true),
		statusSuccess: lipgloss.NewStyle().
			Foreground(success).
			Bold(true),
		inputLabel: lipgloss.NewStyle().
			Foreground(accentSoft).
			Bold(true),
		inputBox: lipgloss.NewStyle().
			Border(lipgloss.RoundedBorder()).
			BorderForeground(border).
			Padding(0, 1).
			Background(panelAlt),
	}
}

func clampFrameWidth(windowWidth int) int {
	const fallback = 84
	if windowWidth <= 0 {
		return fallback
	}
	if windowWidth <= 44 {
		return windowWidth
	}
	if windowWidth > 92 {
		return 92
	}
	return windowWidth - 2
}

func innerWidth(frameWidth int) int {
	if frameWidth <= 10 {
		return frameWidth
	}
	return frameWidth - 6
}

func (t tuiTheme) renderFrame(width int, title, subtitle, body, footer string) string {
	frameWidth := clampFrameWidth(width)
	contentWidth := innerWidth(frameWidth)
	placeWidth := width
	if placeWidth <= 0 {
		placeWidth = frameWidth
	}

	headerLeft := lipgloss.JoinHorizontal(lipgloss.Top, t.badge.Render("SAMBA CONFIGER"), "  ", t.chrome.Render("share editor"))
	headerRule := t.headerBar.Render(strings.Repeat("─", max(0, contentWidth-lipgloss.Width(headerLeft)-1)))
	header := lipgloss.JoinHorizontal(lipgloss.Center, headerLeft, " ", headerRule)

	sections := []string{header, t.title.Width(contentWidth).Render(title)}
	if subtitle != "" {
		sections = append(sections, t.subtitle.Width(contentWidth).Render(subtitle))
	}
	if body != "" {
		sections = append(sections, body)
	}
	if footer != "" {
		sections = append(sections, t.footer.Width(contentWidth).Render(footer))
	}

	return lipgloss.PlaceHorizontal(placeWidth, lipgloss.Center, t.outer.Width(frameWidth).Render(strings.Join(sections, "\n\n")))
}

func (t tuiTheme) renderSection(width int, title string, lines []string) string {
	if len(lines) == 0 {
		return ""
	}

	contentWidth := innerWidth(clampFrameWidth(width))
	rendered := make([]string, 0, len(lines)+1)
	if title != "" {
		rendered = append(rendered, t.sectionTitle.Width(contentWidth).Render(title))
	}
	for _, line := range lines {
		rendered = append(rendered, t.panel.Width(contentWidth).Render(t.body.Width(max(1, contentWidth-2)).Render(line)))
	}
	return strings.Join(rendered, "\n")
}

func (t tuiTheme) renderMessage(width int, kind, text string) string {
	label := t.statusInfo
	switch kind {
	case "warn":
		label = t.statusWarn
	case "success":
		label = t.statusSuccess
	}
	return t.panel.Width(innerWidth(clampFrameWidth(width))).Render(
		label.Render(strings.ToUpper(kind)) + "  " + t.body.Render(text),
	)
}

func max(a, b int) int {
	if a > b {
		return a
	}
	return b
}

type menuOption struct {
	Key         string
	Value       string
	Label       string
	Description string
}

type menuModel struct {
	theme    tuiTheme
	title    string
	subtitle string
	intro    []string
	options  []menuOption
	cursor   int
	choice   string
	cancel   bool
	width    int
}

func (m menuModel) Init() tea.Cmd {
	return nil
}

func (m menuModel) Update(msg tea.Msg) (tea.Model, tea.Cmd) {
	switch msg := msg.(type) {
	case tea.WindowSizeMsg:
		m.width = msg.Width
	case tea.KeyMsg:
		key := strings.ToLower(msg.String())
		switch key {
		case "ctrl+c", "esc":
			m.cancel = true
			return m, tea.Quit
		case "up", "k":
			if len(m.options) > 0 {
				m.cursor = (m.cursor - 1 + len(m.options)) % len(m.options)
			}
		case "down", "j":
			if len(m.options) > 0 {
				m.cursor = (m.cursor + 1) % len(m.options)
			}
		case "enter":
			if len(m.options) > 0 {
				m.choice = m.options[m.cursor].Value
				return m, tea.Quit
			}
		default:
			for i, option := range m.options {
				if key == strings.ToLower(option.Key) || key == fmt.Sprintf("%d", i+1) {
					m.cursor = i
					m.choice = option.Value
					return m, tea.Quit
				}
			}
		}
	}
	return m, nil
}

func (m menuModel) View() string {
	width := clampFrameWidth(m.width)
	if width == 0 {
		width = clampFrameWidth(84)
	}
	contentWidth := innerWidth(width)

	rows := make([]string, 0, len(m.options))
	for i, option := range m.options {
		rowStyle := m.theme.row
		keyStyle := m.theme.rowKey
		titleStyle := m.theme.rowTitle
		hintStyle := m.theme.rowHint
		numberStyle := m.theme.rowNumber
		prefix := numberStyle.Render(fmt.Sprintf("%02d", i+1))
		if i == m.cursor {
			rowStyle = m.theme.rowSelected
			keyStyle = m.theme.rowKeySelected
			titleStyle = m.theme.rowTitleOn
			hintStyle = m.theme.rowHintActive
			numberStyle = m.theme.rowNumberOn
			prefix = numberStyle.Render(">>")
		}

		top := lipgloss.JoinHorizontal(
			lipgloss.Center,
			prefix,
			"  ",
			keyStyle.Render(strings.ToUpper(option.Key)),
			"  ",
			titleStyle.Render(option.Label),
		)

		rowLines := []string{top}
		if option.Description != "" {
			rowLines = append(rowLines, hintStyle.Render(option.Description))
		}
		rows = append(rows, rowStyle.Width(contentWidth).Render(strings.Join(rowLines, "\n")))
	}

	bodyParts := []string{}
	if len(m.intro) > 0 {
		bodyParts = append(bodyParts, m.theme.renderSection(width, "Context", m.intro))
	}
	bodyParts = append(bodyParts, m.theme.sectionTitle.Width(contentWidth).Render("Actions"))
	bodyParts = append(bodyParts, strings.Join(rows, "\n"))

	return m.theme.renderFrame(
		m.width,
		m.title,
		m.subtitle,
		strings.Join(bodyParts, "\n\n"),
		"enter select  •  j/k or arrows move  •  letter/number picks instantly  •  esc cancel",
	)
}

type textPromptModel struct {
	theme        tuiTheme
	title        string
	subtitle     string
	label        string
	defaultValue string
	input        textinput.Model
	value        string
	cancel       bool
	width        int
}

func newTextPromptModel(theme tuiTheme, title, subtitle, label, defaultValue string) textPromptModel {
	input := textinput.New()
	input.Prompt = ""
	input.Placeholder = defaultValue
	input.Focus()
	input.CharLimit = 512
	input.Width = 48

	return textPromptModel{
		theme:        theme,
		title:        title,
		subtitle:     subtitle,
		label:        label,
		defaultValue: defaultValue,
		input:        input,
	}
}

func (m textPromptModel) Init() tea.Cmd {
	return textinput.Blink
}

func (m textPromptModel) Update(msg tea.Msg) (tea.Model, tea.Cmd) {
	switch msg := msg.(type) {
	case tea.WindowSizeMsg:
		m.width = msg.Width
		available := innerWidth(clampFrameWidth(m.width)) - 4
		if available < 16 {
			available = 16
		}
		m.input.Width = available
	case tea.KeyMsg:
		switch msg.String() {
		case "ctrl+c", "esc":
			m.cancel = true
			return m, tea.Quit
		case "enter":
			value := strings.TrimSpace(m.input.Value())
			if value == "" {
				value = m.defaultValue
			}
			m.value = value
			return m, tea.Quit
		}
	}

	var cmd tea.Cmd
	m.input, cmd = m.input.Update(msg)
	return m, cmd
}

func (m textPromptModel) View() string {
	width := clampFrameWidth(m.width)
	contentWidth := innerWidth(width)

	lines := []string{m.theme.inputLabel.Width(contentWidth).Render(m.label)}
	lines = append(lines, m.theme.panelAccent.Width(contentWidth).Render(m.theme.inputBox.Width(max(8, contentWidth-2)).Render(m.input.View())))
	if m.defaultValue != "" {
		lines = append(lines, m.theme.muted.Width(contentWidth).Render("Enter keeps: "+m.defaultValue))
	}

	return m.theme.renderFrame(
		m.width,
		m.title,
		m.subtitle,
		strings.Join(lines, "\n\n"),
		"enter confirm  •  esc cancel",
	)
}

func runMenuPrompt(in io.Reader, out io.Writer, theme tuiTheme, title, subtitle string, intro []string, options []menuOption) (string, error) {
	model := menuModel{
		theme:    theme,
		title:    title,
		subtitle: subtitle,
		intro:    intro,
		options:  options,
	}

	result, err := tea.NewProgram(model, tea.WithInput(in), tea.WithOutput(out)).Run()
	if err != nil {
		return "", err
	}

	final := result.(menuModel)
	if final.cancel {
		return "", ErrCancelled
	}
	return final.choice, nil
}

func runTextPrompt(in io.Reader, out io.Writer, theme tuiTheme, title, subtitle, label, defaultValue string) (string, error) {
	model := newTextPromptModel(theme, title, subtitle, label, defaultValue)

	result, err := tea.NewProgram(model, tea.WithInput(in), tea.WithOutput(out)).Run()
	if err != nil {
		return "", err
	}

	final := result.(textPromptModel)
	if final.cancel {
		return "", ErrCancelled
	}
	return final.value, nil
}