/*
  Scopes for AI agent users — least privilege, declared once, provisioned by script.

  Why this exists: `provisionSandbox.ts` granted `[12, 122, 262, 32, 111, 251]` —
  opaque numeric ids, one fixed scope, one user per environment. Three failures
  in the 2026-07/08 sessions came straight from that:

    1. Production `ai_agent` — documented everywhere as READ-ONLY — actually held
       create/modify on invoices and thirdparties, and DELETE on proposals.
    2. Writing a payment to production required granting a right by hand and
       revoking it after. Twice. A privilege held by nobody is safer than a
       privilege granted ad hoc under time pressure.
    3. A sandbox refresh wiped the agent's proposal rights because they had been
       granted manually and lived nowhere in code.

  The model: one user per (environment × scope), never a single all-powerful
  agent. A session is handed the credentials matching what it is allowed to do,
  and nothing else.

  Rule that admits no exception: **no scope grants DELETE.** The ledger is
  append-only — a wrong entry is offset by a credit note, never removed. Deletion
  stays with the human admin.
*/

/** A scope is a set of Dolibarr permission ids, with the reason it exists. */
export interface Scope {
  /** What this scope is for, in one line — read by the operator at provisioning. */
  purpose: string;
  /** Which environments may hold a user with this scope. */
  environments: ReadonlyArray<"sandbox" | "production">;
  /** Dolibarr permission ids (see PERMISSION_LABELS for what each one is). */
  rights: ReadonlyArray<number>;
}

/**
 * Dolibarr permission ids used below, with their fr_FR label — so a reader can
 * audit a scope without opening the Dolibarr admin UI.
 *
 * VERIFY BEFORE TRUSTING: these ids come from the running instance
 * (`/user/perms.php`) and are stable per Dolibarr version, not across versions.
 * `provisionAiUser.ts --audit` prints the live labels next to each granted id.
 */
export const PERMISSION_LABELS: Readonly<Record<number, string>> = {
  11: "Lire les factures clients",
  12: "Créer/modifier les factures clients",
  14: "Émettre des paiements sur les factures clients",
  // 15 = "Supprimer les factures clients" — DELIBERATELY NEVER GRANTED
  16: "Exporter les factures clients",
  121: "Consulter les tiers",
  122: "Créer/modifier les tiers",
  // 125 = "Supprimer les tiers" — DELIBERATELY NEVER GRANTED
  126: "Exporter les tiers",
  241: "Consulter les propositions commerciales",
  242: "Créer/modifier les propositions commerciales",
  // 244 = "Supprimer les propositions commerciales" — DELIBERATELY NEVER GRANTED
  261: "Consulter les produits/services",
  262: "Créer/modifier les produits/services",
  31: "Lire les comptes bancaires",
  32: "Créer/modifier les comptes bancaires",
  111: "Lire les factures fournisseurs",
  251: "Lire les utilisateurs",
} as const;

const READ_ONLY: ReadonlyArray<number> = [11, 111, 121, 126, 241, 261, 31, 251, 16];

export const SCOPES: Readonly<Record<string, Scope>> = {
  /**
   * The default. Every agent session that only needs to look at the books gets
   * this one — audits, reconciliation reads, TVA preparation, reporting.
   * Valid on production BECAUSE it cannot change anything.
   */
  read: {
    purpose: "Lecture seule — audits, réconciliation, préparation TVA, reporting",
    environments: ["sandbox", "production"],
    rights: READ_ONLY,
  },

  /**
   * Rehearsals. Broad write on the sandbox, because that is what the sandbox is
   * for: a disposable copy where a change-set is tried before a human sees it.
   * Refused on production by the environment list AND by the host guard.
   */
  "sandbox-write": {
    purpose: "Répétition d'un change-set sur la sandbox (factures, tiers, produits, propositions, règlements)",
    environments: ["sandbox"],
    rights: [...READ_ONLY, 12, 122, 262, 242, 14, 32],
  },

  /**
   * The narrow production writer, used ONLY by the gated promote apply, and only
   * for what that step actually does: create/modify invoices, attach payments.
   * No thirdparty creation, no product creation, no proposals — those are
   * rehearsed then applied by a human when they are genuinely needed.
   *
   * Provisioning this user is itself a deliberate act: `--env production`
   * requires the explicit opt-in in guard.ts.
   */
  "prod-write": {
    purpose: "Écriture de production, gated — création/modification de factures et rattachement de règlements",
    environments: ["production"],
    rights: [...READ_ONLY, 12, 14],
  },
} as const;

export type ScopeName = keyof typeof SCOPES;

/** Conventional login for a given scope + environment. One user per pair. */
export function loginFor(scope: string, env: "sandbox" | "production"): string {
  return env === "sandbox" ? `ai_agent_sandbox_${scope.replace(/-/g, "_")}`
                           : `ai_agent_prod_${scope.replace(/-/g, "_")}`;
}

/** Fail loudly rather than provision something nobody declared. */
export function resolveScope(name: string, env: "sandbox" | "production"): Scope {
  const s = SCOPES[name];
  if (!s) {
    throw new Error(
      `unknown scope '${name}'. Declared scopes: ${Object.keys(SCOPES).join(", ")}`,
    );
  }
  if (!s.environments.includes(env)) {
    throw new Error(
      `scope '${name}' is not allowed on '${env}' (allowed: ${s.environments.join(", ")}).\n` +
        "  Scopes are per-environment by design — a sandbox writer has no business holding\n" +
        "  production credentials, and vice versa.",
    );
  }
  return s;
}