import { normalizeOrgChartDataset } from './normalize.js';
import type { Employee, OrgChartDataset, OrgChartSummary, Organization, WorkStatus } from './types.js';

/** Internal content selectors: these do not expand the package's public data API. */
function uniqueEmployees(data: OrgChartDataset): Employee[] {
  const seen = new Set<string>();
  return data.employees.filter(employee => {
    if (seen.has(employee.id)) return false;
    seen.add(employee.id);
    return true;
  });
}

/** Literal unique IDs in their primary organization, including leaders and all statuses.
 * Inclusive organization counts stay in Summary; they must never be summed as a subtotal.
 * Map keys safely retain opaque organization IDs and position names such as __proto__.
 */
export function selectOrganizationPositionCounts(data: OrgChartDataset): ReadonlyMap<string, ReadonlyMap<string, number>> {
  const counts = new Map<string, Map<string, number>>();
  for (const organization of data.organizations) counts.set(organization.id, new Map());
  for (const employee of uniqueEmployees(data)) {
    const row = counts.get(employee.organizationId);
    if (row) row.set(employee.position, (row.get(employee.position) ?? 0) + 1);
  }
  return counts;
}

export function selectAffiliationSummary(data: OrgChartDataset, summary: OrgChartSummary) {
  // Include all declared affiliations, including zero, without recounting employees.
  return data.affiliations.map(affiliation => ({
    affiliation,
    count: summary.raw.byAffiliation[affiliation.id] ?? 0,
  }));
}

export interface MajorOrganizationTotal {
  organization: Organization;
  /** 'direct' for a root's own members (e.g. its leader); 'inclusive' for a major organization. */
  scope: 'direct' | 'inclusive';
  count: number;
}

/** Compact totals for the read-only composition: each root's direct members, then
 * each major (root child) organization including its cells/teams. Primary
 * membership is single, so the rows are disjoint and add up to the raw total. */
export function selectMajorOrganizationTotals(data: OrgChartDataset, summary: OrgChartSummary): MajorOrganizationTotal[] {
  const rows: MajorOrganizationTotal[] = [];
  for (const root of normalizeOrgChartDataset(data).roots) {
    const counts = summary.raw.byOrganization[root.organization.id];
    if (!root.children.length) {
      rows.push({ organization: root.organization, scope: 'inclusive', count: counts?.inclusive ?? 0 });
      continue;
    }
    if (counts?.direct) rows.push({ organization: root.organization, scope: 'direct', count: counts.direct });
    for (const child of root.children) {
      rows.push({ organization: child.organization, scope: 'inclusive', count: summary.raw.byOrganization[child.organization.id]?.inclusive ?? 0 });
    }
  }
  return rows;
}

export interface StatusContentGroup {
  status: Extract<WorkStatus, 'dispatched' | 'onLeave'>;
  employees: readonly Employee[];
  count: number;
}

export function selectStatusGroups(data: OrgChartDataset, summary: OrgChartSummary): StatusContentGroup[] {
  const employees = uniqueEmployees(data);
  const groups: StatusContentGroup[] = [];
  if (data.presentation?.groups.showDispatched !== false) {
    groups.push({ status: 'dispatched', employees: employees.filter(employee => employee.workStatus === 'dispatched'), count: summary.raw.byStatus.dispatched });
  }
  if (data.presentation?.groups.showOnLeave !== false) {
    groups.push({ status: 'onLeave', employees: employees.filter(employee => employee.workStatus === 'onLeave'), count: summary.raw.byStatus.onLeave });
  }
  // Cards retain original Employee references. A second display never changes Summary.
  return groups;
}