// Thin typed fetch wrapper. Token is injected from localStorage (JWT auth — DECISIONS.md).
import type {
  AdminCaseDetail,
  AdminCasesPage,
  CaseDog,
  AdminDog,
  AdminDogsPage,
  AdminOwnerDetail,
  AdminOwnersPage,
  BreedOption,
  BreedEstimateResult,
  DogDetailResult,
  PhotoSearchResult,
  TestMatchResult,
  Case,
  Dataset,
  DatasetDetail,
  DatasetDogsPage,
  EmbedAllResult,
  FoundReportResponse,
  Job,
  KnownDog,
  Match,
  MatchDatasetResult,
  Page,
  PurgeResult,
  ReclaimInfo,
  User,
} from "./types";

const TOKEN_KEY = "pawtrace_token";

export function getToken(): string | null {
  return localStorage.getItem(TOKEN_KEY);
}
export function setToken(t: string | null) {
  if (t) localStorage.setItem(TOKEN_KEY, t);
  else localStorage.removeItem(TOKEN_KEY);
}

export class ApiError extends Error {
  status: number;
  constructor(status: number, message: string) {
    super(message);
    this.status = status;
  }
}

async function request<T>(path: string, opts: RequestInit = {}): Promise<T> {
  const headers = new Headers(opts.headers);
  const token = getToken();
  if (token) headers.set("Authorization", `Bearer ${token}`);
  if (!(opts.body instanceof FormData) && opts.body) {
    headers.set("Content-Type", "application/json");
  }
  const res = await fetch(path, { ...opts, headers });
  if (res.status === 204) return undefined as T;
  const data = await res.json().catch(() => ({}));
  if (!res.ok) {
    const msg = data?.error?.message || data?.detail || res.statusText;
    throw new ApiError(res.status, msg);
  }
  return data as T;
}

export const api = {
  // auth
  register: (body: { name: string; email: string; password: string; zip: string; phone?: string }) =>
    request<{ access_token: string }>("/auth/register", { method: "POST", body: JSON.stringify(body) }),
  login: (body: { email: string; password: string }) =>
    request<{ access_token: string }>("/auth/login", { method: "POST", body: JSON.stringify(body) }),
  me: () => request<User>("/auth/me"),

  // dogs
  listDogs: () => request<Page<KnownDog>>("/dogs"),
  getDog: (id: number) => request<KnownDog>(`/dogs/${id}`),
  createDog: (body: Partial<KnownDog>) =>
    request<KnownDog>("/dogs", { method: "POST", body: JSON.stringify(body) }),
  uploadDogPhotos: (id: number, files: File[]) => {
    const fd = new FormData();
    files.forEach((f) => fd.append("files", f));
    return request<unknown>(`/dogs/${id}/photos`, { method: "POST", body: fd });
  },
  markDogHome: (id: number) => request<KnownDog>(`/dogs/${id}/mark-home`, { method: "POST" }),

  // cases
  createLost: (body: Record<string, unknown>) =>
    request<FoundReportResponse>("/cases/lost", { method: "POST", body: JSON.stringify(body) }),
  createFound: (fd: FormData) =>
    request<FoundReportResponse>("/cases/found", { method: "POST", body: fd }),
  listCases: () => request<Page<Case>>("/cases"),
  getCase: (id: number) => request<Case>(`/cases/${id}`),
  getCaseMatches: (id: number) => request<Match[]>(`/cases/${id}/matches`),
  getCaseDog: (id: number) => request<CaseDog>(`/cases/${id}/dog`),
  widen: (id: number) => request<FoundReportResponse>(`/cases/${id}/widen`, { method: "POST" }),
  widenBreed: (id: number) =>
    request<FoundReportResponse>(`/cases/${id}/widen-breed`, { method: "POST" }),
  rematchCase: (id: number) =>
    request<FoundReportResponse>(`/cases/${id}/rematch`, { method: "POST" }),
  updateCase: (id: number, body: { notes?: string; close?: boolean }) =>
    request<Case>(`/cases/${id}`, { method: "PATCH", body: JSON.stringify(body) }),

  // matches
  confirmMatch: (id: number) => request<Match>(`/matches/${id}/confirm`, { method: "POST" }),
  rejectMatch: (id: number) => request<Match>(`/matches/${id}/reject`, { method: "POST" }),
  reconsiderMatch: (id: number) => request<Match>(`/matches/${id}/reconsider`, { method: "POST" }),
  reclaimInfo: (id: number) => request<ReclaimInfo>(`/matches/${id}/reclaim`),

  // geo
  shelters: (zip?: string) =>
    request<{ zip: string | null; shelters: { name: string; detail: string }[] }>(
      `/geo/nearby-shelters${zip ? `?zip=${encodeURIComponent(zip)}` : ""}`
    ),

  // public runtime config (read on load to decide which UI to render + haystack size for the UI)
  getConfig: () => request<{ demo_mode: boolean; haystack_size: number }>("/config"),

  // public photo search (no auth). Accepts 1-6 images of the same dog — the server scores every
  // query image against every candidate image and keeps the best pair, so more angles only help.
  // pool: "found" searches found/unknown dogs (I lost my dog); "lost" searches known/lost dogs (I
  // found a dog and want its owner).
  searchByPhoto: (files: File[], zip?: string, pool: "found" | "lost" = "found", topK = 12) => {
    const fd = new FormData();
    files.forEach((f) => fd.append("files", f));
    if (zip) fd.append("zip", zip);
    fd.append("top_k", String(topK));
    fd.append("pool", pool);
    return request<PhotoSearchResult>("/search/by-photo", { method: "POST", body: fd });
  },
  // Breed estimation over 1-6 images of the same dog. The server averages the per-label scores
  // across every image — one photo alone can easily flip the top breed.
  estimateBreed: (files: File[], topN = 5) => {
    const fd = new FormData();
    files.forEach((f) => fd.append("files", f));
    fd.append("top_n", String(topN));
    return request<BreedEstimateResult>("/search/breed", { method: "POST", body: fd });
  },

  // admin: datasets / data loading
  listAllDogs: (
    kind: "all" | "known" | "unknown" = "all",
    limit = 30,
    offset = 0,
    opts: {
      breed?: string;
      breedK?: number;
      sort?: "newest" | "oldest";
      zip?: string;
      addedFrom?: string;
      addedTo?: string;
    } = {}
  ) => {
    const p = new URLSearchParams({ kind, limit: String(limit), offset: String(offset) });
    if (opts.breed) {
      p.set("breed", opts.breed);
      p.set("breed_k", String(opts.breedK ?? 10));
    }
    if (opts.sort) p.set("sort", opts.sort);
    if (opts.zip) p.set("zip", opts.zip);
    if (opts.addedFrom) p.set("added_from", opts.addedFrom);
    if (opts.addedTo) p.set("added_to", opts.addedTo);
    return request<AdminDogsPage>(`/admin/dogs?${p}`);
  },
  listBreeds: () => request<{ model: [string, string] | null; breeds: BreedOption[] }>("/admin/breeds"),
  listAllCases: (kind?: "lost" | "found", status?: string, limit = 30, offset = 0) => {
    const q = new URLSearchParams({ limit: String(limit), offset: String(offset) });
    if (kind) q.set("kind", kind);
    if (status) q.set("status", status);
    return request<AdminCasesPage>(`/admin/cases?${q}`);
  },
  listOwners: (limit = 30, offset = 0, q?: string) => {
    const p = new URLSearchParams({ limit: String(limit), offset: String(offset) });
    if (q) p.set("q", q);
    return request<AdminOwnersPage>(`/admin/owners?${p}`);
  },
  getOwnerDetail: (id: number) => request<AdminOwnerDetail>(`/admin/owners/${id}`),
  resetDemo: () =>
    request<{ matches_reset: number; cases_reopened: number; known_relost: number; found_reset: number }>(
      "/admin/reset-demo",
      { method: "POST" },
    ),
  getCaseDetail: (caseId: number) => request<AdminCaseDetail>(`/admin/cases/${caseId}`),
  runCaseMatch: (caseId: number) =>
    request<Match[]>(`/admin/cases/${caseId}/run-match`, { method: "POST" }),
  deleteCase: (caseId: number) =>
    request<{ deleted: Record<string, number> }>(`/admin/cases/${caseId}`, { method: "DELETE" }),
  deleteDog: (kind: "known" | "unknown", dogId: number) =>
    request<{ deleted: Record<string, number> }>(`/admin/dogs/${kind}/${dogId}`, { method: "DELETE" }),
  setDogStatus: (kind: "known" | "unknown", dogId: number, status: string) =>
    request<{ profile: AdminDog }>(`/admin/dogs/${kind}/${dogId}/status`, {
      method: "POST",
      body: JSON.stringify({ status }),
    }),
  deletePerson: (userId: number) =>
    request<{ deleted: Record<string, number> }>(`/admin/owners/${userId}`, { method: "DELETE" }),
  testMatch: (kind: "known" | "unknown", dogId: number, topK = 10, applyBreedGate = false) =>
    request<TestMatchResult>(
      `/admin/test-match?kind=${kind}&dog_id=${dogId}&top_k=${topK}&apply_breed_gate=${applyBreedGate}`
    ),
  getDogDetail: (kind: "known" | "unknown", dogId: number) =>
    request<DogDetailResult>(`/admin/dog/${kind}/${dogId}`),
  listDatasets: () => request<Dataset[]>("/admin/datasets"),
  getDataset: (id: number) => request<DatasetDetail>(`/admin/datasets/${id}`),
  listDatasetDogs: (id: number, limit = 25, offset = 0) =>
    request<DatasetDogsPage>(`/admin/datasets/${id}/dogs?limit=${limit}&offset=${offset}`),
  deleteDataset: (id: number) =>
    request<PurgeResult>(`/admin/datasets/${id}`, { method: "DELETE" }),
  embedAll: (id: number) =>
    request<EmbedAllResult>(`/admin/datasets/${id}/embed-all`, { method: "POST" }),
  startEmbedJob: (id: number) =>
    request<{ job_id: string; status: string }>(`/admin/datasets/${id}/embed-all-job`, {
      method: "POST",
    }),
  matchDataset: (id: number, candidateDatasetId?: number) =>
    request<MatchDatasetResult>(
      `/admin/datasets/${id}/match${candidateDatasetId ? `?candidate_dataset_id=${candidateDatasetId}` : ""}`,
      { method: "POST" }
    ),
  startLoad: (fd: FormData) =>
    request<{ job_id: string; status: string }>("/admin/datasets/load", { method: "POST", body: fd }),
  getJob: (jobId: string) => request<Job>(`/admin/jobs/${jobId}`),
};