/**
 * Knowledge API client — Wiki articles/categories/versions, knowledge graph,
 * and Ask Knowledge.
 *
 * All requests use the shared `apiClient` (`baseURL: '/api/v1'`).
 */

import { apiDelete, apiGet, apiPatch, apiPost } from './client';

// ─── Wiki types ────────────────────────────────────────────────────────────

export type WikiArticleStatus = 'draft' | 'published' | 'archived';

export interface WikiArticle {
  id: string;
  title: string;
  slug: string;
  content: string;
  content_html: string | null;
  summary: string | null;
  category_id: string | null;
  tags: string[];
  status: WikiArticleStatus;
  entity_links: Record<string, unknown>[];
  version: number;
  published_at: string | null;
  owner_id: string | null;
  created_at: string | null;
  updated_at: string | null;
}

export interface WikiArticleListResult {
  items: WikiArticle[];
  total: number;
  page: number;
  page_size: number;
}

export interface WikiArticleCreate {
  title: string;
  slug?: string;
  content?: string;
  summary?: string | null;
  category_id?: string | null;
  tags?: string[];
  status?: WikiArticleStatus;
  entity_links?: Record<string, unknown>[];
}

export interface WikiArticleUpdate {
  title?: string;
  content?: string;
  summary?: string | null;
  category_id?: string | null;
  tags?: string[];
  status?: WikiArticleStatus;
  entity_links?: Record<string, unknown>[];
  edit_comment?: string | null;
}

export interface WikiCategory {
  id: string;
  name: string;
  slug: string;
  description: string | null;
  parent_id: string | null;
  sort_order: number;
}

export interface WikiCategoryCreate {
  name: string;
  slug?: string;
  description?: string | null;
  parent_id?: string | null;
  sort_order?: number;
}

export interface WikiVersion {
  id: string;
  version: number;
  title: string;
  content: string;
  edited_by: string | null;
  edit_comment: string | null;
  created_at: string | null;
}

// ─── Graph types ───────────────────────────────────────────────────────────

export interface GraphRelationship {
  id: string;
  source_type: string;
  source_id: string;
  target_type: string;
  target_id: string;
  relationship_type: string;
  metadata: Record<string, unknown> | null;
  owner_id: string | null;
  created_at: string | null;
}

export interface GraphRelationshipsResult {
  items: GraphRelationship[];
  total: number;
}

// ─── Ask Knowledge types ───────────────────────────────────────────────────

export interface KnowledgeAskRequest {
  query: string;
  source_types?: string[];
}

export interface KnowledgeEvidence {
  id: string;
  source_type: string;
  source_id: string;
  title: string;
  snippet: string;
  score?: number;
  url?: string | null;
}

export interface KnowledgeAskResponse {
  answer: string;
  evidence: KnowledgeEvidence[];
  sources_used?: string[];
}

// ─── Wiki API ──────────────────────────────────────────────────────────────

export async function fetchWikiArticles(params?: {
  page?: number;
  page_size?: number;
  category_id?: string | null;
  status?: string | null;
  search?: string | null;
}): Promise<WikiArticleListResult> {
  const query = new URLSearchParams();
  if (params?.page) query.set('page', String(params.page));
  if (params?.page_size) query.set('page_size', String(params.page_size));
  if (params?.category_id) query.set('category_id', params.category_id);
  if (params?.status) query.set('status', params.status);
  if (params?.search) query.set('search', params.search);
  const qs = query.toString();
  return apiGet<WikiArticleListResult>(`/wiki/articles${qs ? `?${qs}` : ''}`);
}

export async function fetchWikiArticle(articleId: string): Promise<WikiArticle> {
  return apiGet<WikiArticle>(`/wiki/articles/${articleId}`);
}

export async function createWikiArticle(data: WikiArticleCreate): Promise<WikiArticle> {
  return apiPost<WikiArticle>('/wiki/articles', data);
}

export async function updateWikiArticle(articleId: string, data: WikiArticleUpdate): Promise<WikiArticle> {
  return apiPatch<WikiArticle>(`/wiki/articles/${articleId}`, data);
}

export async function deleteWikiArticle(articleId: string): Promise<void> {
  await apiDelete<void>(`/wiki/articles/${articleId}`);
}

export async function fetchWikiVersions(articleId: string): Promise<WikiVersion[]> {
  const result = await apiGet<{ items: WikiVersion[] }>(`/wiki/articles/${articleId}/versions`);
  return result.items;
}

export async function restoreWikiVersion(articleId: string, version: number): Promise<WikiArticle> {
  return apiPost<WikiArticle>(`/wiki/articles/${articleId}/versions/${version}/restore`);
}

export async function fetchWikiCategories(): Promise<WikiCategory[]> {
  const result = await apiGet<{ items: WikiCategory[] }>('/wiki/categories');
  return result.items;
}

export async function createWikiCategory(data: WikiCategoryCreate): Promise<WikiCategory> {
  return apiPost<WikiCategory>('/wiki/categories', data);
}

// ─── Graph API ─────────────────────────────────────────────────────────────

export async function fetchGraphRelationships(params?: {
  source_type?: string | null;
  source_id?: string | null;
  target_type?: string | null;
  target_id?: string | null;
  relationship_type?: string | null;
  page?: number;
  page_size?: number;
}): Promise<GraphRelationshipsResult> {
  const query = new URLSearchParams();
  if (params?.source_type) query.set('source_type', params.source_type);
  if (params?.source_id) query.set('source_id', params.source_id);
  if (params?.target_type) query.set('target_type', params.target_type);
  if (params?.target_id) query.set('target_id', params.target_id);
  if (params?.relationship_type) query.set('relationship_type', params.relationship_type);
  if (params?.page) query.set('page', String(params.page));
  if (params?.page_size) query.set('page_size', String(params.page_size));
  const qs = query.toString();
  return apiGet<GraphRelationshipsResult>(`/graph/relationships${qs ? `?${qs}` : ''}`);
}

// ─── Ask Knowledge API ─────────────────────────────────────────────────────

export async function askKnowledge(body: KnowledgeAskRequest): Promise<KnowledgeAskResponse> {
  return apiPost<KnowledgeAskResponse>('/knowledge/ask', body);
}