package main

import (
	"os"
	"strings"

	"github.com/charmbracelet/lipgloss"
	"github.com/mattn/go-runewidth"
)

// A restrained, high-contrast palette. Text always includes its meaning, so
// colors supplement the UI rather than carrying state by themselves.
type uiTheme struct {
	title, accent, muted, warning, success, active, selected lipgloss.Style
	border                                                   lipgloss.Style
	plain                                                    bool
}

func newTheme() uiTheme {
	t := uiTheme{plain: os.Getenv("NO_COLOR") != "" || strings.EqualFold(os.Getenv("TERM"), "dumb")}
	if t.plain {
		t.title = lipgloss.NewStyle()
		t.accent = lipgloss.NewStyle()
		t.muted = lipgloss.NewStyle()
		t.warning = lipgloss.NewStyle()
		t.success = lipgloss.NewStyle()
		t.active = lipgloss.NewStyle()
		t.selected = lipgloss.NewStyle()
		t.border = lipgloss.NewStyle()
		return t
	}
	t.title = lipgloss.NewStyle().Bold(true).Foreground(lipgloss.Color("#D7E9EF"))
	t.accent = lipgloss.NewStyle().Bold(true).Foreground(lipgloss.Color("#70D6D1"))
	t.muted = lipgloss.NewStyle().Foreground(lipgloss.Color("#8FA6B2"))
	t.warning = lipgloss.NewStyle().Bold(true).Foreground(lipgloss.Color("#FFC078"))
	t.success = lipgloss.NewStyle().Foreground(lipgloss.Color("#A8DDA2"))
	t.active = lipgloss.NewStyle().Foreground(lipgloss.Color("#FFC078"))
	t.selected = lipgloss.NewStyle().Bold(true).Foreground(lipgloss.Color("#F4FAFC")).Background(lipgloss.Color("#244553"))
	t.border = lipgloss.NewStyle().Foreground(lipgloss.Color("#426573"))
	return t
}

func (t uiTheme) status(status string) string {
	label := "[" + safe(status) + "]"
	switch strings.ToLower(status) {
	case "closed", "done":
		return t.muted.Render(label)
	case "open":
		return t.success.Render(label)
	default:
		return t.active.Render(label)
	}
}

func (t uiTheme) heading(section string, count string, width int) string {
	prefix := "▌ TODOAPP  /  "
	section = runewidth.Truncate(safe(section), max(1, width-runewidth.StringWidth(prefix)), "…")
	return t.accent.Render("▌ ") + t.title.Render("TODOAPP") + t.muted.Render("  /  "+section) + "\n" +
		t.muted.Render(runewidth.Truncate(safe(count), max(1, width), "…"))
}

// box frames content only when the terminal has room for a border. The width
// argument is the terminal width, not the inner content width.
func (t uiTheme) box(content string, width, height int) string {
	if width < 50 || height < 14 || t.plain {
		return content
	}
	return t.border.Border(lipgloss.RoundedBorder()).Padding(0, 1).Width(min(width, 100) - 2).Render(content)
}

func (t uiTheme) row(label string, selected bool, width int) string {
	prefix := "  "
	if selected {
		prefix = "› "
	}
	text := runewidth.Truncate(prefix+label, max(1, width), "…")
	if selected {
		return t.selected.Width(min(width, 100)).Render(text)
	}
	return text
}

func (t uiTheme) hint(text string, width int) string {
	return t.muted.Render(runewidth.Truncate(text, max(1, width), "…"))
}

func (t uiTheme) alert(text string, width int) string {
	return t.warning.Render(runewidth.Truncate("! "+safe(text), max(1, width), "…"))
}