/**
 * Document ⇄ condition link helpers shared by the vault routes.
 *
 * One grouped query per page (no N+1), owner-scoped everywhere: every episode
 * id a client sends is re-narrowed against the caller's live episodes before
 * it can land in `document_condition_links`.
 */
import type { Prisma } from "@/generated/prisma/client";
import { prisma } from "@/lib/db";
import { decryptField } from "@/lib/encounters/dto";
import { MAX_PROCEDURES } from "@/lib/encounters/procedures";
import { listTargetsBySource, replaceTargets } from "@/lib/links";
import type {
  DocumentConditionLinkDto,
  DocumentEncounterLinkDto,
  DocumentLinkedProcedureDto,
  DocumentVaccinationLinkDto,
} from "@/lib/validations/inbound-documents";
import {
  CUSTOM_VACCINE_RESOLVE_SELECT,
  customLookupOf,
  resolveVaccineEntry,
} from "@/lib/vaccinations/resolve-vaccine-entry";

/**
 * Load the condition links for a page of documents in ONE grouped query.
 * Returns a map documentId → link DTOs (documents without links are absent).
 */
export async function loadConditionLinks(
  userId: string,
  documentIds: string[],
): Promise<Map<string, DocumentConditionLinkDto[]>> {
  const map = new Map<string, DocumentConditionLinkDto[]>();
  if (documentIds.length === 0) return map;
  // `includeDeletedTargets` keeps the long-standing behaviour: the chip has
  // always come off a relation join with no tombstone filter, so a document
  // filed against a condition the person later deleted still shows it.
  const byDocument = await listTargetsBySource(prisma, {
    userId,
    sourceKind: "document",
    sourceIds: documentIds,
    targetKind: "conditionEpisode",
    includeDeletedTargets: true,
  });
  for (const [documentId, targets] of byDocument) {
    map.set(
      documentId,
      targets.map((target) => ({ episodeId: target.id, name: target.label })),
    );
  }
  return map;
}

/**
 * Load the VISIT links for a page of documents in ONE grouped query.
 *
 * Unlike the condition chips this filters tombstoned visits out: the condition
 * behaviour is a long-standing one this refactor deliberately did not change,
 * while a visit link is new and starts from the honest default — a deleted
 * visit is not something the document still belongs to.
 */
export async function loadDocumentEncounterLinks(
  userId: string,
  documentIds: string[],
): Promise<Map<string, DocumentEncounterLinkDto[]>> {
  const map = new Map<string, DocumentEncounterLinkDto[]>();
  if (documentIds.length === 0) return map;
  const byDocument = await listTargetsBySource(prisma, {
    userId,
    sourceKind: "document",
    sourceIds: documentIds,
    targetKind: "encounter",
  });
  for (const [documentId, targets] of byDocument) {
    map.set(
      documentId,
      targets.map((target) => ({
        encounterId: target.id,
        kind: target.label,
        occurredAt: target.date,
      })),
    );
  }
  return map;
}

/**
 * The record's procedures and surgeries that hold at least one LIVE document
 * link, newest first — the vault filter bar's procedure choices.
 *
 * Every live PROCEDURE visit counts whatever its status: a pre-op letter filed
 * against a booked operation belongs to it as much as the discharge letter
 * belongs to one that happened. Tombstoned visits and tombstoned documents
 * drop out, the same honest default `loadDocumentEncounterLinks` uses. The
 * reason and body site are ciphertext at rest and decrypt through the visit
 * DTO's fail-soft path, so one row with a key gap reads as unnamed rather than
 * failing the usage read. Only the label's columns are selected. Bounded like the procedure history itself.
 */
export async function loadLinkedProcedures(
  userId: string,
): Promise<DocumentLinkedProcedureDto[]> {
  const rows = await prisma.encounter.findMany({
    where: {
      userId,
      deletedAt: null,
      kind: "PROCEDURE",
      documentLinks: { some: { userId, document: { deletedAt: null } } },
    },
    orderBy: [{ occurredAt: "desc" }, { id: "asc" }],
    take: MAX_PROCEDURES,
    // Only what the label needs: no outcome, no practitioner contact fields.
    select: {
      id: true,
      occurredAt: true,
      reasonEncrypted: true,
      bodySiteEncrypted: true,
      laterality: true,
      practitioner: { select: { name: true } },
    },
  });
  return rows.map((row) => ({
    encounterId: row.id,
    occurredAt: row.occurredAt.toISOString(),
    reason: decryptField(row.reasonEncrypted, "reason"),
    bodySite: decryptField(row.bodySiteEncrypted, "bodySite"),
    laterality: row.laterality,
    practitionerName: row.practitioner?.name ?? null,
  }));
}

/**
 * Narrow a client-sent visit-id list to the caller's LIVE visits.
 *
 * Same shape and same refusal as {@link narrowOwnedEpisodeIds}: null when any
 * id names nothing, so an attacker probing another account's visit ids learns
 * only "not found".
 */
export async function narrowOwnedEncounterIds(
  userId: string,
  encounterIds: string[],
): Promise<string[] | null> {
  const unique = [...new Set(encounterIds)];
  if (unique.length === 0) return [];
  const owned = await prisma.encounter.findMany({
    where: { id: { in: unique }, userId, deletedAt: null },
    select: { id: true },
  });
  if (owned.length !== unique.length) return null;
  return unique;
}

/**
 * Replace-set a document's visit links inside the given client.
 *
 * Goes through the link service in the `document → encounter` direction, which
 * is the same table the visit's own sheet writes from the other end, so the two
 * surfaces cannot disagree about what is filed where.
 */
export async function replaceEncounterLinks(
  tx: Prisma.TransactionClient,
  userId: string,
  documentId: string,
  encounterIds: string[],
): Promise<void> {
  await replaceTargets(tx, {
    userId,
    sourceKind: "document",
    sourceId: documentId,
    targetKind: "encounter",
    targetIds: encounterIds,
  });
}

/**
 * Narrow a client-sent episode-id list to the caller's LIVE episodes.
 * Returns the deduplicated owned ids, or null when any id is unknown /
 * foreign / deleted — the caller answers with a 404-shaped refusal (an
 * attacker probing another user's episode ids learns nothing beyond
 * "not found").
 */
export async function narrowOwnedEpisodeIds(
  userId: string,
  episodeIds: string[],
): Promise<string[] | null> {
  const unique = [...new Set(episodeIds)];
  if (unique.length === 0) return [];
  const owned = await prisma.illnessEpisode.findMany({
    where: { id: { in: unique }, userId, deletedAt: null },
    select: { id: true },
  });
  if (owned.length !== unique.length) return null;
  return unique;
}

/**
 * Replace-set a document's condition links inside the given transaction-ish
 * client: delete links no longer in the set, insert the missing ones.
 *
 * `episodeIds` should already be owner-narrowed (`narrowOwnedEpisodeIds`), so
 * the route can answer a foreign id with the 404-shaped refusal it does today.
 * The link service narrows them again regardless — the routes decide the reply,
 * the service decides what reaches the table.
 */
export async function replaceConditionLinks(
  tx: Prisma.TransactionClient,
  userId: string,
  documentId: string,
  episodeIds: string[],
): Promise<void> {
  await replaceTargets(tx, {
    userId,
    sourceKind: "document",
    sourceId: documentId,
    targetKind: "conditionEpisode",
    targetIds: episodeIds,
  });
}

/**
 * Load the VACCINATION links for one or more documents in two grouped
 * queries: the links through the link service, then the doses' identity so
 * the client can name each one from its own bundle.
 *
 * Tombstoned doses drop out, the same honest default the visit links take.
 */
export async function loadDocumentVaccinationLinks(
  userId: string,
  documentIds: string[],
): Promise<Map<string, DocumentVaccinationLinkDto[]>> {
  const map = new Map<string, DocumentVaccinationLinkDto[]>();
  if (documentIds.length === 0) return map;
  const byDocument = await listTargetsBySource(prisma, {
    userId,
    sourceKind: "document",
    sourceIds: documentIds,
    targetKind: "vaccination",
  });
  const doseIds = [
    ...new Set([...byDocument.values()].flat().map((target) => target.id)),
  ];
  if (doseIds.length === 0) return map;
  const doses = await prisma.vaccinationRecord.findMany({
    where: { id: { in: doseIds }, userId },
    select: {
      id: true,
      antigenSlug: true,
      vaccineName: true,
      customVaccineId: true,
      customVaccine: { select: CUSTOM_VACCINE_RESOLVE_SELECT },
    },
  });
  const doseById = new Map(doses.map((dose) => [dose.id, dose]));
  const customs = customLookupOf(doses.map((dose) => dose.customVaccine));
  for (const [documentId, targets] of byDocument) {
    map.set(
      documentId,
      targets.map((target) => {
        const dose = doseById.get(target.id);
        const entry = dose ? resolveVaccineEntry(dose, customs) : null;
        return {
          vaccinationId: target.id,
          occurredAt: target.date,
          catalogSlug: entry?.slug ?? null,
          // A dose logged against the person's own definition and carrying no
          // wording of its own is named by that definition.
          vaccineName: dose?.vaccineName ?? entry?.name ?? null,
        };
      }),
    );
  }
  return map;
}

/**
 * Narrow a client-sent dose-id list to the caller's LIVE doses. Same shape
 * and same refusal as {@link narrowOwnedEncounterIds}.
 */
export async function narrowOwnedVaccinationIds(
  userId: string,
  vaccinationIds: string[],
): Promise<string[] | null> {
  const unique = [...new Set(vaccinationIds)];
  if (unique.length === 0) return [];
  const owned = await prisma.vaccinationRecord.findMany({
    where: { id: { in: unique }, userId, deletedAt: null },
    select: { id: true },
  });
  if (owned.length !== unique.length) return null;
  return unique;
}

/**
 * Replace-set a document's vaccination links through the link service, in
 * the `document → vaccination` direction of the table the dose's own form
 * writes.
 */
export async function replaceVaccinationLinks(
  tx: Prisma.TransactionClient,
  userId: string,
  documentId: string,
  vaccinationIds: string[],
): Promise<void> {
  await replaceTargets(tx, {
    userId,
    sourceKind: "document",
    sourceId: documentId,
    targetKind: "vaccination",
    targetIds: vaccinationIds,
  });
}