import { readFile } from "node:fs/promises";

import { posix, relative, isAbsolute } from "node:path";

import { CLI, quote, parse, record } from "./cli.ts";

import type { Sandbox } from "./runtime.ts";

/** Map host-project absolute paths to the guest; unrelated absolute paths are already guest paths. */

let guestScript: Promise<string> | undefined;

export function remotePath(path: string, box: Sandbox): string {

if (isAbsolute(path)) {

const delta = relative(box.source, path);

if (delta === "" || (!delta.startsWith("../") && delta !== ".."))

return posix.join(box.cwd, delta);

return path;

}

return posix.resolve(box.cwd, path);

}

export class Files {

private locks = new Map<string, Promise<unknown>>();

constructor(private cli: CLI) {}

async execute(

box: Sandbox,

op: string,

args: Record<string, unknown>,

signal?: AbortSignal,

): Promise<unknown> {

// Serialize file operations per box so edit's read/replace cannot race another tool edit.

const previous = this.locks.get(box.id) ?? Promise.resolve();

const task = previous.catch(() => {}).then(() => this.run(box, op, args, signal));

this.locks.set(box.id, task);

try {

return await task;

} finally {

if (this.locks.get(box.id) === task) this.locks.delete(box.id);

}

}

private async run(

box: Sandbox,

op: string,

input: Record<string, unknown>,

signal?: AbortSignal,

): Promise<unknown> {

signal?.throwIfAborted();

const args = { ...input };

for (const key of ["path", "filePath"])

if (typeof args[key] === "string") args[key] = remotePath(args[key], box);

if (typeof args.patchText === "string") {

args.patchText = args.patchText.replace(

/^(\*\*\* (?:Add File|Update File|Delete File|Move to): )(.+)$/gm,

(_, prefix, path) => prefix + remotePath(path, box),

);

}

const request = JSON.stringify({ op, args, cwd: box.cwd });

if (Buffer.byteLength(request) > 2 * 1024 * 1024)

throw new Error("File operation exceeds 2 MiB");

const root = `/tmp/opencode-createos-${crypto.randomUUID()}`;

await this.cli.script(box.id, `mkdir -m 700 ${quote(root)}`, signal);

try {

guestScript ??= readFile(new url(/sitelet?url=https%3A%2F%2Fgithub.com%2FNodeOps-app%2Fcreateos-plugins%2Fblob%2Fmain%2Fpackages%2Fopencode-plugin%2Fsrc%2F%26quot%3B.%2Fguest.py%26quot%3B%2C%2520import.meta.url), "utf8");

await Promise.all([

guestScript.then((script) => this.cli.push(box.id, root + "/guest.py", script, signal)),

this.cli.push(box.id, root + "/input.json", request, signal),

]);

const result = await this.cli.execute(

box.id,

`python3 ${quote(root + "/guest.py")} < ${quote(root + "/input.json")}`,

box.cwd,

120_000,

signal,

);

const data = record(parse(result));

if (result.code !== 0 || data.error) throw new Error(String(data.error ?? result.stderr));

return data.result;

} finally {

await this.cli.script(box.id, `rm -rf -- ${quote(root)}`);

}

}

}