/**
 * Centralized API client for all backend communication.
 *
 * Every fetch call in the app should go through here so that
 * endpoint URLs live in one place and are easy to update
 * (e.g. when adding multi-node support with /api/nodes/{id}/...).
 */

// ---------------------------------------------------------------------------
// Pages
// ---------------------------------------------------------------------------

export interface PageMeta {
  name: string;
  title: string | null;
  published: boolean;
  has_source: boolean;
  last_modified: number | null;
  size: number | null;
}

export interface PageDetail {
  name: string;
  source: string | null;
}

export async function fetchPages(): Promise<PageMeta[]> {
  const res = await fetch("/api/pages");
  return res.json();
}

export async function fetchPage(name: string): Promise<PageDetail> {
  const res = await fetch(`/api/pages/${name}`);
  return res.json();
}

export async function savePage(
  name: string,
  source: string,
  publish: boolean,
): Promise<PageMeta> {
  const res = await fetch(`/api/pages/${name}`, {
    method: "POST",
    headers: { "Content-Type": "application/json" },
    body: JSON.stringify({ source, publish }),
  });
  if (!res.ok) throw new Error(await res.text());
  return res.json();
}

export async function deletePage(name: string): Promise<void> {
  await fetch(`/api/pages/${name}`, { method: "DELETE" });
}

// ---------------------------------------------------------------------------
// Compile
// ---------------------------------------------------------------------------

export interface CompileResult {
  ascii: string;
  micron: string;
  script: string;
  is_dynamic: boolean;
  warnings: string[];
}

export async function compile(
  source: string,
  signal?: AbortSignal,
): Promise<CompileResult> {
  const res = await fetch("/api/compile", {
    method: "POST",
    headers: { "Content-Type": "application/json" },
    body: JSON.stringify({ source }),
    signal,
  });
  if (!res.ok) {
    const err = await res.json().catch(() => ({ detail: "Compile failed" }));
    throw new Error(err.detail || "Compile failed");
  }
  return res.json();
}

// ---------------------------------------------------------------------------
// DSL Metadata
// ---------------------------------------------------------------------------

export interface DslCommand {
  label: string;
  detail: string;
  section: string;
  snippet: string;
}

export interface DslMeta {
  keywords: string[];
  values: string[];
  commands: DslCommand[];
  themes: string[];
}

export async function fetchDslMeta(): Promise<DslMeta> {
  const res = await fetch("/api/dsl-meta");
  return res.json();
}

// ---------------------------------------------------------------------------
// Node Management
// ---------------------------------------------------------------------------

export async function restartNode(): Promise<void> {
  const res = await fetch("/api/restart", { method: "POST" });
  if (!res.ok) throw new Error(await res.text());
}

// ---------------------------------------------------------------------------
// Images
// ---------------------------------------------------------------------------

export interface UploadResult {
  filename: string;
  path: string;
}

export async function uploadImage(file: File): Promise<UploadResult> {
  const form = new FormData();
  form.append("file", file);
  const res = await fetch("/api/upload-image", { method: "POST", body: form });
  if (!res.ok) throw new Error(await res.text());
  return res.json();
}