import { parseAllDocuments } from "yaml";
import { z } from "zod";
import type { WorkspaceDescriptor } from "./schema.js";

export const CATALOG_PATH = "thoth-workspaces.yaml";

export interface WorkspaceCatalogEntry {
  id: string;
  name: string;
  description?: string;
}

export interface WorkspaceCatalog {
  schema_version: 1;
  workspaces: WorkspaceCatalogEntry[];
}

const workspaceId = z.string().trim().regex(/^[a-z][a-z0-9-]{2,62}$/, {
  message: "workspace id must match ^[a-z][a-z0-9-]{2,62}$",
}).refine((value) => value !== "workspace-docs", {
  message: "workspace id is reserved",
});

const catalogEntry = z.object({
  id: workspaceId,
  name: z.string().trim().min(1),
  description: z.string().trim().min(1).optional(),
}).strict();

const catalogSchema = z.object({
  schema_version: z.literal(1),
  workspaces: z.array(catalogEntry),
}).strict().superRefine((catalog, context) => {
  const seen = new Set<string>();
  catalog.workspaces.forEach((entry, index) => {
    if (seen.has(entry.id)) {
      context.addIssue({
        code: "custom",
        path: ["workspaces", index, "id"],
        message: "workspace id is duplicated in the catalog",
      });
    }
    seen.add(entry.id);
  });
});

function safeCatalogError(): Error {
  return new Error("Workspace catalog is invalid");
}

export function parseWorkspaceCatalogYaml(source: string): WorkspaceCatalog {
  try {
    const documents = parseAllDocuments(source, { uniqueKeys: true });
    if (documents.length !== 1) throw safeCatalogError();
    const document = documents[0];
    if (document.errors.length > 0 || document.warnings.length > 0) throw safeCatalogError();
    return catalogSchema.parse(document.toJSON()) as WorkspaceCatalog;
  } catch (error) {
    if (error instanceof Error && error.message === "Workspace catalog is invalid") throw error;
    throw safeCatalogError();
  }
}

export function assertCatalogMatchesDescriptor(
  entry: WorkspaceCatalogEntry,
  workspace: WorkspaceDescriptor,
): void {
  if (
    entry.id !== workspace.workspace.id
    || entry.name !== workspace.workspace.name
    || entry.description !== workspace.workspace.description
  ) {
    throw new Error("Workspace catalog metadata does not match descriptor");
  }
}