import { App, TFile, TFolder, normalizePath } from "obsidian";
import { PROJECTS_ROOT, PROJECT_FILES, TO_UPDATE_DIR } from "./const";

export type Zone = "ready" | "to-update";

export function projectsPath(): string {
  return PROJECTS_ROOT;
}

export function projectPath(name: string): string {
  return normalizePath(`${PROJECTS_ROOT}/${name}`);
}

export function toUpdatePath(project: string): string {
  return normalizePath(`${PROJECTS_ROOT}/${project}/${TO_UPDATE_DIR}`);
}

export function zoneRootPath(project: string, zone: Zone): string {
  return zone === "ready" ? projectPath(project) : toUpdatePath(project);
}

export function areaPath(project: string, area: string, zone: Zone = "ready"): string {
  return normalizePath(`${zoneRootPath(project, zone)}/${area}`);
}

export function featurePath(
  project: string,
  area: string,
  feature: string,
  zone: Zone = "ready",
): string {
  const file = feature.endsWith(".md") ? feature : `${feature}.md`;
  return normalizePath(`${zoneRootPath(project, zone)}/${area}/${file}`);
}

export async function ensureFolder(app: App, path: string): Promise<void> {
  const p = normalizePath(path);
  const exists = app.vault.getAbstractFileByPath(p);
  if (!exists) {
    await app.vault.createFolder(p);
  }
}

export async function ensureFile(app: App, path: string, content = ""): Promise<TFile> {
  const p = normalizePath(path);
  const existing = app.vault.getAbstractFileByPath(p);
  if (existing instanceof TFile) return existing;
  return await app.vault.create(p, content);
}

export function listFolders(app: App, path: string): TFolder[] {
  const p = normalizePath(path);
  const folder = app.vault.getAbstractFileByPath(p);
  if (!(folder instanceof TFolder)) return [];
  return folder.children
    .filter((c): c is TFolder => c instanceof TFolder)
    .sort((a, b) => a.name.localeCompare(b.name));
}

export function listMarkdownFiles(app: App, path: string, exclude: string[] = []): TFile[] {
  const p = normalizePath(path);
  const folder = app.vault.getAbstractFileByPath(p);
  if (!(folder instanceof TFolder)) return [];
  return folder.children
    .filter((c): c is TFile => c instanceof TFile && c.extension === "md")
    .filter((f) => !exclude.includes(f.name))
    .sort((a, b) => a.basename.localeCompare(b.basename));
}

export async function readFile(app: App, path: string): Promise<string> {
  const p = normalizePath(path);
  const f = app.vault.getAbstractFileByPath(p);
  if (!(f instanceof TFile)) return "";
  return await app.vault.read(f);
}

export async function deleteRecursive(app: App, path: string): Promise<void> {
  const p = normalizePath(path);
  const f = app.vault.getAbstractFileByPath(p);
  if (!f) return;
  await app.vault.delete(f, true);
}

export async function rename(app: App, oldPath: string, newPath: string): Promise<void> {
  const f = app.vault.getAbstractFileByPath(normalizePath(oldPath));
  if (!f) return;
  await app.fileManager.renameFile(f, normalizePath(newPath));
}

export async function createProject(app: App, name: string): Promise<void> {
  const root = projectPath(name);
  await ensureFolder(app, projectsPath());
  await ensureFolder(app, root);
  for (const file of PROJECT_FILES) {
    await ensureFile(app, normalizePath(`${root}/${file}`), "");
  }
  await createArea(app, name, "story");
}

export async function createArea(
  app: App,
  project: string,
  area: string,
  zone: Zone = "to-update",
): Promise<void> {
  if (zone === "to-update") await ensureFolder(app, toUpdatePath(project));
  await ensureFolder(app, areaPath(project, area, zone));
}

export async function createFeature(
  app: App,
  project: string,
  area: string,
  feature: string,
  zone: Zone = "ready",
): Promise<TFile> {
  return await ensureFile(app, featurePath(project, area, feature, zone), "");
}

export function projectFeaturePath(
  project: string,
  feature: string,
  zone: Zone = "ready",
): string {
  const file = feature.endsWith(".md") ? feature : `${feature}.md`;
  return normalizePath(`${zoneRootPath(project, zone)}/${file}`);
}

export async function createProjectFeature(
  app: App,
  project: string,
  feature: string,
  zone: Zone = "to-update",
): Promise<TFile> {
  if (zone === "to-update") await ensureFolder(app, toUpdatePath(project));
  return await ensureFile(app, projectFeaturePath(project, feature, zone), "");
}

export function isProjectRootFile(name: string): boolean {
  return (PROJECT_FILES as readonly string[]).includes(name);
}

export interface ProjectFileLocation {
  project: string;
  area?: string;
  zone: Zone;
}

export function parseProjectFilePath(path: string): ProjectFileLocation | null {
  if (!path.endsWith(".md")) return null;
  const parts = normalizePath(path).split("/");
  if (parts[0] !== PROJECTS_ROOT) return null;
  if (parts.length < 3) return null;
  const project = parts[1];
  const rest = parts.slice(2);
  let zone: Zone = "ready";
  if (rest[0] === TO_UPDATE_DIR) {
    zone = "to-update";
    rest.shift();
  }
  if (rest.length === 1) return { project, zone };
  if (rest.length === 2) return { project, area: rest[0], zone };
  return null;
}