package tui

import (
	"fmt"
	"strings"

	tea "github.com/charmbracelet/bubbletea"
	"github.com/charmbracelet/lipgloss"

	"tuistream-play/internal/player"
)

func (m Model) updatePlaying(msg tea.Msg) (tea.Model, tea.Cmd) {
	key, ok := msg.(tea.KeyMsg)
	if !ok || m.plr == nil {
		return m, nil
	}
	switch key.String() {
	case "ctrl+c":
		m.plr.Stop()
		m.plr = nil
		return m, tea.Quit
	case "q", "esc":
		cmd := m.endPlayback(m.plr.Snapshot())
		return m, cmd
	case " ", "k":
		m.plr.TogglePause()
	case "left":
		m.plr.SeekRelative(-10)
	case "right":
		m.plr.SeekRelative(10)
	case "shift+left":
		m.plr.SeekRelative(-60)
	case "shift+right":
		m.plr.SeekRelative(60)
	case "up", "+", "=":
		m.plr.AdjustVolume(5)
	case "down", "-":
		m.plr.AdjustVolume(-5)
	case "m":
		m.plr.ToggleMute()
	case "n", ">", ".":
		// Next track (audio queues only). Falls through silently if there's
		// no next track or the current item isn't part of an audio queue.
		if m.nowPlaying.AudioOnly() {
			if next := m.nextAudioIndex(m.queueIdx); next >= 0 {
				return m.advanceTo(next)
			}
		}
	case "p", "<", ",":
		// Previous track (audio queues only).
		if m.nowPlaying.AudioOnly() {
			if prev := m.prevAudioIndex(m.queueIdx); prev >= 0 {
				return m.advanceTo(prev)
			}
		}
	}
	return m, nil
}

func (m Model) viewPlaying() string {
	// During a track change advanceTo briefly nils the player before the next
	// one starts; render a placeholder instead of dereferencing nil.
	if m.plr == nil {
		return lipgloss.JoinVertical(lipgloss.Left,
			m.headerBar(),
			" "+m.st.muted.Render("Loading…"),
			"",
			m.footerBar("q stop", ""),
		)
	}
	snap := m.plr.Snapshot()

	state := m.st.good.Render("▶ playing")
	if snap.Paused {
		state = m.st.accent.Render("⏸ paused")
	}

	title := m.st.title.Render(displayTitle(m.nowPlaying))
	sub := m.st.muted.Render(displayDesc(m.nowPlaying))
	times := m.st.muted.Render(fmt.Sprintf("%s / %s", formatTime(snap.TimePos), formatTime(snap.Duration)))
	bar := m.progressBar(snap.TimePos, snap.Duration)
	vol := m.volumeLine(snap)

	help := "space pause · ←/→ ±10s · ↑/↓ vol · m mute · q stop"
	if m.nowPlaying.AudioOnly() {
		help = "space pause · ←/→ ±10s · n/p track · ↑/↓ vol · m mute · q stop"
	}

	body := strings.Join([]string{
		"",
		"  " + title,
		"  " + sub,
		"",
		"  " + state + "   " + times,
		"  " + bar,
		"",
		"  " + vol,
		"",
	}, "\n")
	label := "Now Playing"
	if m.nowPlaying.AudioOnly() {
		label = "♪ Now Playing (audio)"
	}
	return lipgloss.JoinVertical(lipgloss.Left,
		m.headerBar(),
		" "+m.st.muted.Render(label),
		body,
		m.footerBar(help, ""),
	)
}

// volumeLine renders a compact volume indicator: a short bar plus the percent,
// or a muted marker. mpv's range is 0-130; the bar is scaled to 0-100 so the
// common case fills it, with amplification (>100) simply pinning it full.
func (m Model) volumeLine(s player.State) string {
	if s.Muted {
		return m.st.muted.Render("vol  ") + m.st.bad.Render("muted")
	}
	const width = 16
	ratio := s.Volume / 100.0
	if ratio < 0 {
		ratio = 0
	}
	if ratio > 1 {
		ratio = 1
	}
	fill := int(ratio * float64(width))
	bar := m.st.barFill.Render(strings.Repeat("▮", fill)) +
		m.st.barEmpty.Render(strings.Repeat("▯", width-fill))
	return m.st.muted.Render("vol  ") + bar + m.st.muted.Render(fmt.Sprintf("  %.0f%%", s.Volume))
}

// progressBar renders a fixed-width bar from the elapsed/total ratio.
func (m Model) progressBar(pos, dur float64) string {
	width := m.width - 10
	if width < 10 {
		width = 40
	}
	if width > 80 {
		width = 80
	}
	ratio := 0.0
	if dur > 0 {
		ratio = pos / dur
	}
	if ratio < 0 {
		ratio = 0
	}
	if ratio > 1 {
		ratio = 1
	}
	fill := int(ratio * float64(width))
	return m.st.barFill.Render(strings.Repeat("━", fill)) +
		m.st.barEmpty.Render(strings.Repeat("─", width-fill))
}

// formatTime renders seconds as H:MM:SS or M:SS.
func formatTime(sec float64) string {
	if sec < 0 {
		sec = 0
	}
	s := int(sec)
	h := s / 3600
	mn := (s % 3600) / 60
	ss := s % 60
	if h > 0 {
		return fmt.Sprintf("%d:%02d:%02d", h, mn, ss)
	}
	return fmt.Sprintf("%d:%02d", mn, ss)
}