import Foundation /// Maps Codex `additional_rate_limits` entries (model-specific limits such as GPT-5.3-Codex-Spark)/// into named extra rate windows.////// These limits are reported by the `wham/usage` API alongside, but separately from, the primary and/// weekly Codex windows, so we surface them through `UsageSnapshot.extraRateWindows` rather than the core/// primary/secondary lanes. When the field is absent the mapper returns an empty list and the snapshot is/// unchanged.enum CodexAdditionalRateLimitMapper {    /// Stable ids/titles for GPT-5.3-Codex-Spark limits so SwiftUI identity stays constant even if the API    /// label wording shifts. Keep the original 5-hour id for compatibility with the first Spark implementation.    static let sparkWindowID = "codex-spark"    static let sparkWeeklyWindowID = "codex-spark-weekly"    static let sparkWindowTitle = "Codex Spark 5-hour"    static let sparkWeeklyWindowTitle = "Codex Spark Weekly"     static func extraRateWindows(        from additionalRateLimits: [CodexUsageResponse.AdditionalRateLimit]?,        now: Date = Date()) -> [NamedRateWindow]    {        guard let additionalRateLimits, !additionalRateLimits.isEmpty else { return [] }        var usedIDs = Set<String>()        return additionalRateLimits.flatMap { entry in            self.namedWindows(from: entry, usedIDs: &usedIDs, now: now)        }    }     private static func namedWindows(        from entry: CodexUsageResponse.AdditionalRateLimit,        usedIDs: inout Set<String>,        now: Date) -> [NamedRateWindow]    {        if self.isSpark(entry) {            return self.sparkWindows(from: entry, usedIDs: &usedIDs, now: now)        }         // Model-specific limits report utilization in the primary window; fall back to the secondary        // window only when a primary one is not present.        guard let snapshot = entry.rateLimit?.primaryWindow ?? entry.rateLimit?.secondaryWindow else {            return []        }        guard let id = self.windowID(for: entry), usedIDs.insert(id).inserted else { return [] }        return [self.namedWindow(            id: id,            title: self.windowTitle(for: entry),            snapshot: snapshot,            now: now)]    }     private static func sparkWindows(        from entry: CodexUsageResponse.AdditionalRateLimit,        usedIDs: inout Set<String>,        now: Date) -> [NamedRateWindow]    {        let candidates: [(CodexUsageResponse.WindowSnapshot?, SparkWindowKind)] = [            (entry.rateLimit?.primaryWindow, .fiveHour),            (entry.rateLimit?.secondaryWindow, .weekly),        ]         return candidates.compactMap { snapshot, fallbackKind in            guard let snapshot else { return nil }            let kind = self.sparkWindowKind(for: snapshot, fallback: fallbackKind)            guard usedIDs.insert(kind.id).inserted else { return nil }            return self.namedWindow(id: kind.id, title: kind.title, snapshot: snapshot, now: now)        }    }     private static func namedWindow(        id: String,        title: String,        snapshot: CodexUsageResponse.WindowSnapshot,        now: Date) -> NamedRateWindow    {        let resetDate: Date? = snapshot.resetAt > 0            ? Date(timeIntervalSince1970: TimeInterval(snapshot.resetAt))            : nil        let window = RateWindow(            usedPercent: Double(snapshot.usedPercent),            windowMinutes: snapshot.limitWindowSeconds > 0 ? snapshot.limitWindowSeconds / 60 : nil,            resetsAt: resetDate,            resetDescription: resetDate.map { UsageFormatter.resetDescription(from: $0, now: now) })        return NamedRateWindow(id: id, title: title, window: window)    }     private enum SparkWindowKind {        case fiveHour        case weekly         var id: String {            switch self {            case .fiveHour: CodexAdditionalRateLimitMapper.sparkWindowID            case .weekly: CodexAdditionalRateLimitMapper.sparkWeeklyWindowID            }        }         var title: String {            switch self {            case .fiveHour: CodexAdditionalRateLimitMapper.sparkWindowTitle            case .weekly: CodexAdditionalRateLimitMapper.sparkWeeklyWindowTitle            }        }    }     private static func sparkWindowKind(        for snapshot: CodexUsageResponse.WindowSnapshot,        fallback: SparkWindowKind) -> SparkWindowKind    {        let minutes = snapshot.limitWindowSeconds > 0 ? snapshot.limitWindowSeconds / 60 : 0        if minutes > 0, minutes <= 6 * 60 { return .fiveHour }        if minutes >= 6 * 24 * 60 { return .weekly }        return fallback    }     private static func windowID(for entry: CodexUsageResponse.AdditionalRateLimit) -> String? {        guard let source = self.firstNonEmpty(entry.meteredFeature, entry.limitName) else { return nil }        let slug = self.slug(source)        return slug.isEmpty ? nil : "codex-\(slug)"    }     private static func windowTitle(for entry: CodexUsageResponse.AdditionalRateLimit) -> String {        self.firstNonEmpty(entry.limitName, entry.meteredFeature) ?? "Codex extra limit"    }     private static func isSpark(_ entry: CodexUsageResponse.AdditionalRateLimit) -> Bool {        [entry.limitName, entry.meteredFeature]            .compactMap { $0?.lowercased() }            .contains { $0.contains("spark") }    }     private static func firstNonEmpty(_ values: String?...) -> String? {        for value in values {            let trimmed = value?.trimmingCharacters(in: .whitespacesAndNewlines)            if let trimmed, !trimmed.isEmpty { return trimmed }        }        return nil    }     private static func slug(_ value: String) -> String {        var result = ""        var lastWasDash = false        for scalar in value.lowercased().unicodeScalars {            if CharacterSet.alphanumerics.contains(scalar) {                result.unicodeScalars.append(scalar)                lastWasDash = false            } else if !lastWasDash {                result.append("-")                lastWasDash = true            }        }        return result.trimmingCharacters(in: CharacterSet(charactersIn: "-"))    }}