import { apiRequest, getPath } from './client.js';

const DEFAULT_LIST_PAGE_LIMIT = 100;

function unwrapEntryPayload(payload) {
  return payload?.data || payload?.entry || payload?.item || payload;
}

function unwrapListPayload(payload) {
  if (Array.isArray(payload)) {
    return payload;
  }

  return payload?.data || payload?.entries || payload?.items || payload?.groups || [];
}

function hasExplicitPagination(filters = {}) {
  return (
    (filters.limit !== undefined && filters.limit !== null)
    || (filters.offset !== undefined && filters.offset !== null)
  );
}

async function fetchAllListPages(store, path, baseQuery = {}) {
  const items = [];
  let offset = 0;

  while (true) {
    const payload = await apiRequest(store, path, {
      query: {
        ...baseQuery,
        limit: DEFAULT_LIST_PAGE_LIMIT,
        offset,
      },
    });
    const pageItems = unwrapListPayload(payload);
    items.push(...pageItems);

    if (pageItems.length < DEFAULT_LIST_PAGE_LIMIT) {
      break;
    }

    offset += DEFAULT_LIST_PAGE_LIMIT;
  }

  return items;
}

export async function searchItemDefinitions(store, query) {
  if (query.trim().length <= 2) {
    return [];
  }

  const payload = await apiRequest(store, `${getPath('items')}/grouped`, {
    query: { search_name: query, expanded: 0 },
  });

  if (Array.isArray(payload)) {
    return payload;
  }

  return payload?.data || payload?.items || [];
}

export async function listStockEntries(store, filters = {}) {
  const baseQuery = {};
  const searchName = filters.searchName || filters.search_name;
  if (searchName) {
    baseQuery.search_name = searchName;
  }

  if (hasExplicitPagination(filters)) {
    const query = { ...baseQuery };
    if (filters.limit !== undefined && filters.limit !== null) {
      query.limit = filters.limit;
    }
    if (filters.offset !== undefined && filters.offset !== null) {
      query.offset = filters.offset;
    }

    const payload = await apiRequest(store, getPath('items'), {
      query,
    });

    return unwrapListPayload(payload);
  }

  return fetchAllListPages(store, getPath('items'), baseQuery);
}

export async function listGroupedStockEntries(store, options = {}) {
  const baseQuery = {};
  const expanded = options.expanded ?? 1;
  baseQuery.expanded = expanded;
  const searchName = options.searchName || options.search_name;
  if (searchName) {
    baseQuery.search_name = searchName;
  }

  if (hasExplicitPagination(options)) {
    const query = { ...baseQuery };
    if (options.limit !== undefined && options.limit !== null) {
      query.limit = options.limit;
    }
    if (options.offset !== undefined && options.offset !== null) {
      query.offset = options.offset;
    }

    const payload = await apiRequest(store, `${getPath('items')}/grouped`, {
      query,
    });

    return unwrapListPayload(payload);
  }

  return fetchAllListPages(store, `${getPath('items')}/grouped`, baseQuery);
}

export async function getStockEntry(store, stockId) {
  const payload = await apiRequest(store, `${getPath('items')}/${stockId}`);
  return unwrapEntryPayload(payload);
}

export async function createStockEntry(store, body) {
  const payload = await apiRequest(store, getPath('items'), {
    method: 'POST',
    body,
    query: { label: 1, print: 1 },
  });
  return unwrapEntryPayload(payload);
}

function normalizeUpsertResponse(payload) {
  return {
    status: payload?.status || null,
    mode: payload?.mode || null,
    operation: payload?.operation || null,
    matchType: payload?.match_type || null,
    matchedItem: payload?.matched_item || null,
    item: payload?.item || null,
    payload: payload?.payload || null,
  };
}

function normalizeIdentifierLookupResponse(payload) {
  return {
    status: payload?.status || null,
    source: payload?.source || null,
    cacheHit: Boolean(payload?.cache_hit),
    identifierCode: payload?.identifier_code || null,
    identifierType: payload?.identifier_type || null,
    item: payload?.item || null,
    payloadFetchedAt: payload?.payload_fetched_at || null,
    retryAfterSeconds:
      Number.isInteger(payload?.retry_after_seconds) ? payload.retry_after_seconds : null,
    staleCache: Boolean(payload?.stale_cache),
  };
}

function normalizeItemLookupResponse(payload) {
  return {
    status: payload?.status || null,
    found: Boolean(payload?.found),
    update: Boolean(payload?.update),
    identifierCode: payload?.identifier_code || null,
    identifierType: payload?.identifier_type || null,
    preview: payload?.preview || null,
    updatedFields: Array.isArray(payload?.updated_fields) ? payload.updated_fields : [],
    offPayloadFetchedAt: payload?.off_payload_fetched_at || null,
    retryAfterSeconds:
      Number.isInteger(payload?.retry_after_seconds) ? payload.retry_after_seconds : null,
    staleCache: Boolean(payload?.stale_cache),
    item: payload?.item || null,
  };
}

export async function previewItemUpsert(store, body) {
  const payload = await apiRequest(store, `${getPath('items')}/upsert`, {
    method: 'POST',
    body,
    query: { mode: 'preview' },
  });

  return normalizeUpsertResponse(payload);
}

export async function applyItemUpsert(store, body) {
  const payload = await apiRequest(store, `${getPath('items')}/upsert`, {
    method: 'POST',
    body,
    query: { mode: 'apply' },
  });

  return normalizeUpsertResponse(payload);
}

export async function lookupItemByIdentifier(store, identifierCode) {
  const payload = await apiRequest(store, `${getPath('items')}/lookup`, {
    method: 'POST',
    body: {
      identifier_code: String(identifierCode || '').trim(),
    },
  });

  return normalizeIdentifierLookupResponse(payload);
}

export async function lookupItemDetails(store, uuidB64, { update = false } = {}) {
  const payload = await apiRequest(store, `${getPath('items')}/${uuidB64}/lookup`, {
    method: 'POST',
    query: { update: update ? 1 : 0 },
  });

  return normalizeItemLookupResponse(payload);
}

export async function patchStockItem(store, uuidB64, body) {
  const payload = await apiRequest(store, `${getPath('items')}/${uuidB64}`, {
    method: 'PATCH',
    body,
  });
  return unwrapEntryPayload(payload);
}

export async function updateStockItem(store, uuidB64, body) {
  await apiRequest(store, `${getPath('items')}/${uuidB64}/stock`, {
    method: 'POST',
    body,
  });
  return getStockEntry(store, uuidB64);
}

export async function deleteStockItem(store, uuidB64) {
  const payload = await apiRequest(store, `${getPath('items')}/${uuidB64}`, {
    method: 'DELETE',
  });
  return unwrapEntryPayload(payload);
}

export async function useStockItem(store, uuidB64) {
  try {
    await apiRequest(store, `${getPath('items')}/${uuidB64}/use`, {
      method: 'POST',
    });
    return { status: 'used' };
  } catch (error) {
    const status = error?.status || error?.cause?.status;
    if (status === 409 || status === 404) {
      return { status: 'already_gone' };
    }

    throw error;
  }
}

export async function adjustStockEntry(store, stockId, body) {
  await apiRequest(store, `${getPath('items')}/${stockId}/stock`, {
    method: 'POST',
    body,
  });
  return getStockEntry(store, stockId);
}

export async function listKitchenChanges(store, { since, limit = 10 } = {}) {
  const payload = await apiRequest(store, getPath('changes'), {
    query: {
      since,
      limit,
    },
  });

  return {
    since: payload?.since || null,
    nextCursor: payload?.next_cursor || null,
    changes: Array.isArray(payload?.changes) ? payload.changes : [],
  };
}