// ── Format Utilities ───────────────────────────────────────────
// Ported from web/src/lib/format.ts

import Foundation

// MARK: - Duration Formatting

/// Format seconds as HH:MM:SS or MM:SS
func formatDuration(_ seconds: TimeInterval) -> String {
    guard seconds > 0 else { return "00:00" }
    let totalSeconds = Int(seconds)
    let hours = totalSeconds / 3600
    let minutes = (totalSeconds % 3600) / 60
    let secs = totalSeconds % 60

    if hours > 0 {
        return String(format: "%02d:%02d:%02d", hours, minutes, secs)
    }
    return String(format: "%02d:%02d", minutes, secs)
}

/// Format seconds as compact string: "2h 15m", "45m", "30s"
func formatDurationCompact(_ seconds: TimeInterval) -> String {
    guard seconds > 0 else { return "0s" }
    let totalSeconds = Int(seconds)
    let hours = totalSeconds / 3600
    let minutes = (totalSeconds % 3600) / 60
    let secs = totalSeconds % 60

    if hours > 0 && minutes > 0 { return "\(hours)h \(minutes)m" }
    if hours > 0 { return "\(hours)h" }
    if minutes > 0 && secs > 0 && minutes < 5 { return "\(minutes)m \(secs)s" }
    if minutes > 0 { return "\(minutes)m" }
    return "\(secs)s"
}

/// Format a date as relative time: "in 5m", "2h ago", "now"
func formatRelativeTime(_ targetTime: Date, now: Date = Date()) -> String {
    let diff = targetTime.timeIntervalSince(now)
    let absDiff = abs(diff)

    if absDiff < 30 { return "now" }

    let compact = formatDurationCompact(absDiff)
    return diff > 0 ? "in \(compact)" : "\(compact) ago"
}

/// Format time as "10:42 AM"
func formatTime(_ date: Date) -> String {
    let formatter = DateFormatter()
    formatter.dateFormat = "h:mm a"
    return formatter.string(from: date)
}

/// Format date as "Mon, Feb 27"
func formatDate(_ date: Date) -> String {
    let formatter = DateFormatter()
    formatter.dateFormat = "EEE, MMM d"
    return formatter.string(from: date)
}

/// Format full date-time as "Mon, Feb 27 at 10:42 AM"
func formatDateTime(_ date: Date) -> String {
    "\(formatDate(date)) at \(formatTime(date))"
}