import type {
  Service,
  Contrat,
  Champ,
  Action,
  ActionLogin,
  Membre,
  Pair,
} from '../types/contract';
import type { LoginPath, SignatureRequirement } from '../types/identity';

/**
 * Cache local pour les objets du graphe.
 */
interface GraphCache {
  services: Map<string, Service>;
  contrats: Map<string, Contrat>;
  champs: Map<string, Champ>;
  actions: Map<string, Action>;
  membres: Map<string, Membre>;
  pairs: Map<string, Pair>;
}

/**
 * Service de résolution du graphe contractuel.
 */
export class GraphResolver {
  private cache: GraphCache;

  constructor() {
    this.cache = {
      services: new Map(),
      contrats: new Map(),
      champs: new Map(),
      actions: new Map(),
      membres: new Map(),
      pairs: new Map(),
    };
  }

  /**
   * Add a service to the cache.
   */
  addService(service: Service): void {
    this.cache.services.set(service.uuid, service);
  }

  /**
   * Add a contrat to the cache.
   */
  addContrat(contrat: Contrat): void {
    this.cache.contrats.set(contrat.uuid, contrat);
  }

  /**
   * Add a champ to the cache.
   */
  addChamp(champ: Champ): void {
    this.cache.champs.set(champ.uuid, champ);
  }

  /**
   * Add an action to the cache.
   */
  addAction(action: Action): void {
    this.cache.actions.set(action.uuid, action);
  }

  /**
   * Add a membre to the cache.
   */
  addMembre(membre: Membre): void {
    this.cache.membres.set(membre.uuid, membre);
  }

  /**
   * Add a pair to the cache.
   */
  addPair(pair: Pair): void {
    this.cache.pairs.set(pair.uuid, pair);
  }

  /**
   * Get all services from cache.
   */
  getServices(): Service[] {
    return Array.from(this.cache.services.values());
  }

  /**
   * Get all membres from cache.
   */
  getMembres(): Membre[] {
    return Array.from(this.cache.membres.values());
  }

  /**
   * Get all contrats from cache.
   */
  getContrats(): Contrat[] {
    return Array.from(this.cache.contrats.values());
  }

  /**
   * Get all pairs from cache.
   */
  getPairs(): Pair[] {
    return Array.from(this.cache.pairs.values());
  }

  /**
   * Get all actions from cache.
   */
  getActions(): Action[] {
    return Array.from(this.cache.actions.values());
  }

  /**
   * Resolve login path: Service → Contrat → Champ → ActionLogin → Membre → Pair.
   */
  resolveLoginPath(
    serviceUuid: string,
    membreUuid: string,
  ): LoginPath | null {
    const service = this.cache.services.get(serviceUuid);
    if (service === undefined) {
      return null;
    }

    const contrat = this.cache.contrats.get(service.contrat_uuid);
    if (contrat === undefined) {
      return {
        service_uuid: serviceUuid,
        contrat_uuid: [],
        action_login_uuid: '',
        membre_uuid: membreUuid,
        pairs_attendus: [],
        signatures_requises: [],
        statut: 'incomplet',
      };
    }
    const contratVersion = contrat.version;

    const champs = Array.from(this.cache.champs.values()).filter((c) =>
      c.contrats_parents_uuid.includes(service.contrat_uuid),
    );

    const membre = this.cache.membres.get(membreUuid);
    if (membre === undefined) {
      return {
        service_uuid: serviceUuid,
        contrat_uuid: [service.contrat_uuid],
        contrat_version: contratVersion,
        champ_uuid: champs.map((c) => c.uuid),
        action_login_uuid: '',
        membre_uuid: membreUuid,
        pairs_attendus: [],
        signatures_requises: [],
        statut: 'incomplet',
      };
    }

    const actionLogin = this.findActionLogin(membre.actions_parents_uuid);
    if (actionLogin === null) {
      return {
        service_uuid: serviceUuid,
        contrat_uuid: [service.contrat_uuid],
        contrat_version: contratVersion,
        champ_uuid: champs.map((c) => c.uuid),
        action_login_uuid: '',
        membre_uuid: membreUuid,
        pairs_attendus: [],
        signatures_requises: [],
        statut: 'incomplet',
      };
    }

    const pairsAttendus = Array.from(this.cache.pairs.values())
      .filter((p) => p.membres_parents_uuid.includes(membreUuid))
      .map((p) => p.uuid);

    const signaturesRequises = this.computeRequiredSignatures(
      actionLogin,
      membreUuid,
    );

    const statut =
      pairsAttendus.length > 0 && signaturesRequises.length > 0
        ? 'complet'
        : 'incomplet';

    return {
      service_uuid: serviceUuid,
      contrat_uuid: [service.contrat_uuid],
      contrat_version: contratVersion,
      champ_uuid: champs.map((c) => c.uuid),
      action_login_uuid: actionLogin.uuid,
      membre_uuid: membreUuid,
      pairs_attendus: pairsAttendus,
      signatures_requises: signaturesRequises,
      statut,
    };
  }

  /**
   * Find action login from action UUIDs.
   */
  private findActionLogin(actionUuids: string[]): ActionLogin | null {
    for (const uuid of actionUuids) {
      const action = this.cache.actions.get(uuid);
      if (action !== undefined && this.isActionLogin(action)) {
        return action as ActionLogin;
      }
    }
    return null;
  }

  /**
   * Check if an action is a login action.
   */
  private isActionLogin(action: Action): boolean {
    return (
      action.types.types_names_chiffres.includes('login') ||
      action.types.types_uuid.some((uuid) => uuid.includes('login'))
    );
  }

  /**
   * Compute required signatures from validators.
   */
  private computeRequiredSignatures(
    action: Action,
    membreUuid: string,
  ): SignatureRequirement[] {
    const requirements: SignatureRequirement[] = [];

    for (const membreRole of action.validateurs_action.membres_du_role) {
      if (membreRole.membre_uuid === membreUuid) {
        for (const sigReq of membreRole.signatures_obligatoires) {
          requirements.push({
            membre_uuid: sigReq.membre_uuid,
            pair_uuid: undefined,
            cle_publique: sigReq.cle_publique,
            cardinalite_minimale: sigReq.cardinalite_minimale,
          });
        }
      }
    }

    return requirements;
  }

  /**
   * Validate that all required parents exist (at least 1 constraint).
   */
  validateParentsConstraints(): {
    valid: boolean;
    errors: string[];
  } {
    const errors: string[] = [];

    for (const champ of this.cache.champs.values()) {
      if (champ.contrats_parents_uuid.length === 0) {
        errors.push(`Champ ${champ.uuid} has no parent contrat`);
      }
    }

    for (const action of this.cache.actions.values()) {
      if (action.contrats_parents_uuid.length === 0) {
        errors.push(`Action ${action.uuid} has no parent contrat`);
      }
    }

    for (const membre of this.cache.membres.values()) {
      if (membre.actions_parents_uuid.length === 0) {
        errors.push(`Membre ${membre.uuid} has no parent action`);
      }
    }

    for (const pair of this.cache.pairs.values()) {
      if (pair.membres_parents_uuid.length === 0) {
        errors.push(`Pair ${pair.uuid} has no parent membre`);
      }
    }

    return {
      valid: errors.length === 0,
      errors,
    };
  }
}