// Utils/Constants.swift
// ---------------------
// Central place for app-wide constants.

import Foundation

// MARK: - Server selection

/// The two known JQC servers the inspector can connect to.
nonisolated enum ServerOption: String, CaseIterable, Sendable {
    case primary   = "https://jqc.ltservicesinc.com"
    case secondary = "https://jqc1.ltservicesinc.com"

    var displayName: String {
        switch self {
        case .primary:   return "jqc (Primary)"
        case .secondary: return "jqc1 (Secondary)"
        }
    }
}

/// Runtime-mutable server selection backed by UserDefaults.
/// Read `ServerConfig.current` anywhere you would have used `Constants.baseURL`.
nonisolated enum ServerConfig {

    private static let defaultsKey = "com.jqc.selectedServer"

    /// The currently selected base URL.  Reads UserDefaults on every call so
    /// actor-isolated callers (e.g. APIClient) always get the latest value
    /// without needing @MainActor access.
    nonisolated static var current: String {
        get {
            let raw = UserDefaults.standard.string(forKey: defaultsKey) ?? ""
            return ServerOption(rawValue: raw)?.rawValue ?? ServerOption.primary.rawValue
        }
    }

    /// Persist the chosen server.  Call from @MainActor UI code only.
    @MainActor
    static func select(_ option: ServerOption) {
        UserDefaults.standard.set(option.rawValue, forKey: defaultsKey)
    }

    /// The current selection as a `ServerOption` (for UI binding).
    @MainActor
    static var selectedOption: ServerOption {
        let raw = UserDefaults.standard.string(forKey: defaultsKey) ?? ""
        return ServerOption(rawValue: raw) ?? .primary
    }

    /// Resolve a photo URL, preferring an absolute server-provided URL
    /// (presigned R2 on the s3 backend, absolute-static on local) and falling
    /// back to building one from the relative 'uploads/...' key for older
    /// servers that don't send the *_url fields.
    nonisolated static func mediaURL(absolute: String?, path: String) -> URL? {
        if let a = absolute, !a.isEmpty { return URL(string: a) }
        guard !path.isEmpty else { return nil }
        return URL(string: current + "/static/" + path)
    }
}

// MARK: - App-wide constants

// Explicitly not @MainActor — these constants must be readable from
// any actor context including APIClient and KeychainHelper.
nonisolated enum Constants {

    nonisolated enum Keychain {
        static let accessToken  = "com.jqc.accessToken"
        static let refreshToken = "com.jqc.refreshToken"
        static let userId       = "com.jqc.userId"
        static let userRole     = "com.jqc.userRole"
        static let username     = "com.jqc.username"
        static let displayName  = "com.jqc.displayName"
        static let deviceId     = "com.jqc.deviceId"
    }

    static let tokenRefreshBufferMinutes: Double = 5

    // MARK: - Roles
    //
    // The server's role strings, and the ONE definition of which of them the
    // app treats as an inspector. This mirrors `User.INSPECTOR_ROLES` /
    // `User.is_inspector` in the Flask app (see server rule 87).
    //
    // Why this exists: `external_inspector` (displayed as "Customer Inspector"
    // — an inspector employed by the customer) has exactly the same powers as
    // our own `inspector`, and the API scopes it identically. The views here
    // were hand-written as `role == "admin" || role == "director" || role ==
    // "inspector"`, so every one of them silently locked customer inspectors
    // out of actions the SERVER was perfectly willing to accept — Update
    // Status, Handled By, Start Follow-up. The failure is invisible: no error,
    // the control simply isn't drawn.
    //
    // Add a role in ONE place here; never re-write the literals in a view.
    nonisolated enum Roles {
        static let admin             = "admin"
        static let director          = "director"
        static let projectManager    = "project_manager"
        static let auditor           = "auditor"
        static let inspector         = "inspector"
        /// "Customer Inspector" — employed by the customer, same powers as
        /// `inspector`, scoped to their assigned contracts.
        static let externalInspector = "external_inspector"

        /// Both inspector roles. Test membership of this, never `== inspector`.
        static let inspectorRoles: Set<String> = [inspector, externalInspector]

        /// May change an issue's status / handler, and start a follow-up.
        /// Matches what the API actually accepts for these actions; the server
        /// remains the authority and additionally enforces facility scope.
        ///
        /// Built from `inspectorRoles` (already a Set) rather than from an
        /// array literal: `[a, b, c].union(...)` does not compile, because the
        /// literal is typed as Array before `.union` is looked up, and Array
        /// has no such member — the annotation on the left does not reach back
        /// into the receiver.
        static let issueActors: Set<String> =
            inspectorRoles.union([admin, director, projectManager])

        static func isInspector(_ role: String) -> Bool {
            inspectorRoles.contains(role)
        }
    }
}