package tui

import (
	"fmt"

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

	"tuistream-play/internal/api"
)

func (m Model) updateBrowse(msg tea.Msg) (tea.Model, tea.Cmd) {
	// Nothing loaded yet (initial Views fetch in flight).
	if len(m.stack) == 0 {
		if key, ok := msg.(tea.KeyMsg); ok && (key.String() == "ctrl+c" || key.String() == "q") {
			return m, tea.Quit
		}
		return m, nil
	}

	cur := &m.stack[len(m.stack)-1]
	filtering := cur.FilterState() == list.Filtering

	if key, ok := msg.(tea.KeyMsg); ok && !filtering {
		switch key.String() {
		case "ctrl+c", "q":
			return m, tea.Quit
		case "esc", "backspace", "h", "left":
			if len(m.stack) > 1 {
				m.stack = m.stack[:len(m.stack)-1]
			}
			return m, nil
		case "c":
			return m, m.loadResume()
		case "enter", "l", "right":
			sel, ok := cur.SelectedItem().(listItem)
			if !ok {
				return m, nil
			}
			it := sel.item
			if it.Playable() {
				m.status = "Starting mpv…"
				// Capture the sibling list as the play queue so audio can
				// auto-advance. Built from the current level's items in their
				// displayed order.
				m.queue, m.queueIdx = currentItems(*cur), cur.Index()
				return m, m.startPlayback(it)
			}
			return m, m.loadChildren(displayTitle(it), it.ID)
		}
	}

	var cmd tea.Cmd
	m.stack[len(m.stack)-1], cmd = cur.Update(msg)
	return m, cmd
}

func (m Model) viewBrowse() string {
	if len(m.stack) == 0 {
		return lipgloss.JoinVertical(lipgloss.Left,
			m.headerBar(), "", m.st.muted.Render("  Loading libraries…"))
	}
	cur := m.stack[len(m.stack)-1]
	help := "enter play/open · c continue · / filter · esc back · q quit"
	return lipgloss.JoinVertical(lipgloss.Left,
		m.headerBar(),
		"",
		cur.View(),
		m.footerBar(help, m.status),
	)
}

// currentItems extracts the api.Items from a list, in display order, so the
// playback queue mirrors exactly what the user sees.
func currentItems(l list.Model) []api.Item {
	rows := l.Items()
	out := make([]api.Item, 0, len(rows))
	for _, r := range rows {
		if li, ok := r.(listItem); ok {
			out = append(out, li.item)
		}
	}
	return out
}

// ---- display helpers ----

func displayTitle(it api.Item) string {
	switch it.Type {
	case "Episode":
		if it.ParentIndexNumber > 0 && it.IndexNumber > 0 {
			return fmt.Sprintf("S%02dE%02d  %s", it.ParentIndexNumber, it.IndexNumber, it.Name)
		}
		if it.IndexNumber > 0 {
			return fmt.Sprintf("%d.  %s", it.IndexNumber, it.Name)
		}
	case "Audio":
		if it.IndexNumber > 0 {
			return fmt.Sprintf("%d.  %s", it.IndexNumber, it.Name)
		}
	case "Movie", "Series":
		if it.ProductionYear > 0 {
			return fmt.Sprintf("%s (%d)", it.Name, it.ProductionYear)
		}
	}
	return it.Name
}

func displayDesc(it api.Item) string {
	var parts []string
	switch it.Type {
	case "CollectionFolder", "UserView":
		if it.CollectionType != "" {
			parts = append(parts, it.CollectionType)
		} else {
			parts = append(parts, "library")
		}
	case "Episode":
		if it.SeriesName != "" {
			parts = append(parts, it.SeriesName)
		}
	case "Series", "Season":
		parts = append(parts, "folder")
	default:
		if it.IsFolder {
			parts = append(parts, "folder")
		}
	}
	if d := formatDuration(it.RunTimeTicks); d != "" {
		parts = append(parts, d)
	}
	if it.UserData.Played {
		parts = append(parts, "✓ watched")
	} else if it.UserData.PlayedPercentage > 1 {
		parts = append(parts, fmt.Sprintf("%.0f%%", it.UserData.PlayedPercentage))
	}
	if len(parts) == 0 {
		return " "
	}
	out := parts[0]
	for _, p := range parts[1:] {
		out += " · " + p
	}
	return out
}

// formatDuration turns RunTimeTicks (100ns units) into "1h 23m" / "12m".
func formatDuration(ticks int64) string {
	if ticks <= 0 {
		return ""
	}
	secs := ticks / 1e7
	h := secs / 3600
	mn := (secs % 3600) / 60
	if h > 0 {
		return fmt.Sprintf("%dh %02dm", h, mn)
	}
	return fmt.Sprintf("%dm", mn)
}