/**
 * Read a file from the workspace. Mirrors `tools/fs/read.rs`.
 */
import * as fs from "node:fs";
import type { JsonValue } from "@zesdex/domain";
import { type Tool, type ToolCtx } from "../mod.ts";
import { argStr, resolvePath } from "../util.ts";

/** Read the contents of a file. */
export class Read implements Tool {
  name = "read";
  description = "Read the contents of a file";

  parameters = {
    type: "object",
    properties: {
      path: { type: "string", description: "Path to the file to read (relative to workspace root)" },
    },
    required: ["path"],
  };

  run(ctx: ToolCtx, args: JsonValue): string {
    const rel = argStr(args, "path");
    const file = resolvePath(ctx.workspaces, rel);
    if (!fs.existsSync(file)) {
      throw new Error(`file '${rel}' does not exist`);
    }
    if (!fs.statSync(file).isFile()) {
      throw new Error(`'${rel}' is not a file`);
    }
    return fs.readFileSync(file, "utf8");
  }
}