/** Accès serveur → moteur QC26 (FastAPI). Côté client, les appels passent par le rewrite /api. */
export const ENGINE_URL = process.env.QC26_ENGINE_URL || "http://127.0.0.1:8201";
export const SITE_URL = process.env.NEXT_PUBLIC_SITE_URL || "https://www.qc26.ca";

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

export async function api<T>(path: string, opts: { revalidate?: number; cache?: RequestCache } = {}): Promise<T> {
  const url = `${ENGINE_URL}${path}`;
  const res = await fetch(url, {
    next: { revalidate: opts.revalidate ?? 60 },
    cache: opts.cache,
    headers: { accept: "application/json" },
  });
  if (!res.ok) throw new ApiError(res.status, `${res.status} ${path}`);
  return res.json() as Promise<T>;
}

export async function apiSafe<T>(path: string, opts: { revalidate?: number } = {}): Promise<T | null> {
  try {
    return await api<T>(path, opts);
  } catch {
    return null;
  }
}

// ------------------------------------------------------------------ types
export type PartyId = "caq" | "plq" | "pq" | "qs" | "pcq";
export type PartyKey = PartyId | "aut";

export interface Meta {
  electionDate: string;
  electionName: string;
  campaignStart: string;
  pollsCloseLocal: string;
  seatsTotal: number;
  majority: number;
  daysToElection: number;
  mode: "forecast" | "live" | "archive";
  simulation: boolean;
  modelVersion: string;
  latestRun: { id: number; completedAt: string | null; pollCount: number; modelVersion: string } | null;
  parties: RegistryParty[];
  others: { id: string; label: string; color: string };
  pollRegions: Record<string, string>;
  topics: Record<string, string>;
  axes: Record<string, { label: string; left: string; right: string }>;
  disclaimer: string;
}

export interface RegistryParty {
  id: PartyId;
  abbreviation: string;
  officialName: string;
  shortName: string;
  color: string;
  secondaryColor: string;
  website: string;
  dgeqId: string;
  colorNote: string;
  order: number;
}

export interface PartyForecast {
  voteMean: number;
  voteSd: number;
  vote80: [number, number];
  vote95: [number, number];
  seatsMean: number;
  seatsMedian: number;
  seats80: [number, number];
  seats95: [number, number];
  pMostSeats: number;
  pMajority: number;
  seatDistribution: number[] | null;
}

export interface TrendPoint {
  date: string;
  mean: Record<string, number>;
  sd: Record<string, number>;
  n_polls: number;
}

export interface ForecastSummaryParty {
  vote: number;
  vote_sd: number;
  vote80: [number, number];
  seats: number;
  seats_mean: number;
  seats80: [number, number];
  seats95: [number, number];
  p_most_seats: number;
  p_majority: number;
}

export interface Forecast {
  id: number;
  modelVersion: string;
  dataCutoff: string;
  completedAt: string | null;
  pollCount: number;
  nSimulations: number;
  seed: number;
  codeCommit: string | null;
  trigger: string | null;
  summary: {
    seats_total: number;
    majority: number;
    parties: Record<string, ForecastSummaryParty>;
    p_minority: number;
    leader: string;
    poll_count: number;
    latest_poll: string;
    national_now: Record<string, number>;
    cutoff: string;
    days_to_election: number;
    battlegrounds: number[];
    ridings: Record<string, { fav: string; p: number; second: string; margin: number }>;
  };
  diff: {
    previous_run: number;
    previous_at: string | null;
    changes: Record<string, { vote: number; seats: number; p_majority: number; p_most_seats: number }>;
    flips: { code: number; from: string; to: string; p: number }[];
    causes: { kind: string; detail: string | string[] }[];
  } | null;
  parties: Record<string, PartyForecast>;
  trend: TrendPoint[] | null;
}

export interface Party extends RegistryParty {
  leader: string | null;
  leaderSince: string | null;
  dgeqName: string | null;
  spokespersons: string | null;
  candidatesCount: number;
  seats2022: number;
  vote2022: number | null;
  forecast: { voteMean: number; seatsMedian: number; seats80: [number, number]; pMajority: number; pMostSeats: number } | null;
  documents: number;
  proposals: number;
}

export interface RidingListItem {
  code: number;
  name: string;
  slug: string;
  region: string | null;
  regionName: string | null;
  electors: number | null;
  isNew: boolean;
  changed: boolean;
  incumbent: { party: string | null; name: string | null; running: boolean | null };
  centroid: [number | null, number | null];
  forecast: { favorite: string; p: number; runnerUp: string | null; margin: number; rating: string; swing: number; pWin: Record<string, number> } | null;
  live: { status: string; leader: string | null; bureaux: [number, number]; marginPct: number | null } | null;
}

export interface Poll {
  id: string;
  pollster: { id: string; name: string };
  sponsor: string | null;
  publicationDate: string | null;
  fieldworkStart: string | null;
  fieldworkEnd: string;
  sampleSize: number | null;
  population: string | null;
  methodology: string | null;
  mode: string | null;
  marginOfError: number | null;
  sourceUrl: string | null;
  sourceTier: string;
  extractionMethod: string;
  confidence: number;
  validated: boolean;
  excluded: boolean;
  exclusionReason: string | null;
  undecided: number | null;
  results: Record<string, number>;
  resultsPage: number | null;
  ingestedAt: string | null;
  document: { id: number; sha256: string; pages: number | null; bytes: number; contentType: string | null; downloadedAt: string; archiveUrl: string } | null;
  weight: { weight: number; recency: number; sample: number; impact: Record<string, number> | null } | null;
  validation: { checks?: string[]; warnings?: string[]; sum?: number } | null;
  nonPrimarySource: boolean;
  subsamples?: Record<string, Record<string, Record<string, number | null>>>;
  leadership?: { question: string; page: number; values: Record<string, number> }[] | null;
  llmNotes?: string[] | null;
  houseEffects?: Record<string, number>;
  audit?: { ts: string; actor: string; field: string | null; old: string | null; new: string | null; reason: string | null }[];
}

export interface LiveState {
  mode: string;
  simulation: boolean;
  seatsNow: Record<string, { elected: number; leading: number }>;
  lastValid: { snapshot_id: number; at: string; source_updated_at: string | null; reporting: number; simulated: boolean } | null;
  quarantine: boolean;
  quarantineReason: string | null;
  snapshot: { id: number; fetchedAt: string; sourceUpdatedAt: string | null; reporting: number; total: number; bureaux: [number, number]; final: boolean } | null;
  nowcast: {
    id: number;
    ts: string;
    majority: number;
    reporting: number;
    coverage: number;
    p_minority: number;
    parties: Record<string, { elected: number; leading: number; total_now: number; seats_mean: number; seats_median: number; seats80: [number, number]; p_majority: number; p_most_seats: number; vote_est: number | null }>;
    projected_now: number[];
  } | null;
  ridings: Record<string, { status: string; leader: string | null; leaderCandidate: string | null; bureaux: [number, number]; votes: number; marginVotes: number | null; marginPct: number | null; turnout: number | null; candidates: { name: string; party_id: string; votes: number; share: number }[] | null; final: boolean }>;
  nowcastRidings: Record<string, { p: number[]; est: number[]; w: number }> | null;
  seatsTotal: number;
  majority: number;
}