import { ModelPolicy, ModelWithPolicies } from "@/domain/model-policies";
import str from "@/hooks/use-string";

export default class AuthService {
  private globalPolicies: Record<string, Record<string, boolean>> = {};

  public setGlobalPolicies(
    policies: Record<string, Record<string, boolean>>,
  ): void {
    this.globalPolicies = policies;
  }

  /**
   * Vérifie une permission globale (create, viewAny)
   */
  public canGlobal(action: string, modelClass: string): boolean {
    const key = AuthService.getPolicyKey(modelClass);
    return (this.globalPolicies[key]?.[action] as boolean) ?? false;
  }

  /**
   * Vérifie une permission contextuelle sur une instance (update, delete, etc.)
   */
  public static canContextual(
    action: keyof ModelPolicy,
    model: ModelWithPolicies,
  ): boolean {
    return model.policies?.[action] ?? false;
  }

  /**
   * Vérifie intelligemment une permission globale ou contextuelle
   */
  public can(action: string, subject: string | ModelWithPolicies): boolean {
    // * Global action on a model class
    if (typeof subject === "string") {
      return this.canGlobal(action, subject);
    }

    // * Global action on a model instance
    if (action === "create" || action === "viewAny") {
      return this.canGlobal(action, subject.modelClass);
    }

    // * Contextual action on a model instance
    return AuthService.canContextual(action as keyof ModelPolicy, subject);
  }

  private static getPolicyKey(modelClass: string): string {
    const parts = modelClass.split("\\");
    const basename = parts.at(-1) || modelClass;
    return str(basename).camelCase().plural().value();
  }
}