// Copyright 2021-present 650 Industries. All rights reserved.

import ExpoModulesJSI

/**
 `BaseModule` is just a stub class that fulfils `AnyModule` protocol requirement of public default initializer,
 but doesn't implement that protocol explicitly, though — it would have to provide a definition which would require
 other modules to use `override` keyword in the function returning the definition.
 */
open class BaseModule {
  public private(set) weak var appContext: AppContext?

  @available(*, unavailable, message: "Module's initializer cannot be overriden, use \"onCreate\" definition component instead.")
  public init() {}

  required public init(appContext: AppContext) {
    self.appContext = appContext
  }

  /**
   Sends an event with given name and body to JavaScript.
   */
  public func sendEvent(_ eventName: String, _ body: [String: Any?] = [:]) {
    appContext?.eventEmitter?.sendEvent(withName: eventName, body: body)
  }
}

extension BaseModule: EventEmitter {
  /**
   Lends the module's JavaScript object, looked up from the module registry, for the duration of `body`.
   */
  @JavaScriptActor
  public func withEventTarget<R>(_ body: (borrowing JavaScriptObject) throws -> R) rethrows -> R? {
    guard let appContext else {
      return nil
    }
    let holder = appContext.moduleRegistry.first { $0.module === self }

    return try holder?.withEventTarget(body) ?? nil
  }
}

/**
 An alias for `AnyModule` extended by the `BaseModule` class that provides public default initializer.
 */
public typealias Module = AnyModule & BaseModule