import process from "node:process";

const chunks = [];

for await (const chunk of process.stdin) {
  chunks.push(chunk);
}

let event;

try {
  event = JSON.parse(Buffer.concat(chunks).toString("utf8") || "{}");
} catch {
  deny("Raw protection could not parse the tool request.");
}

const toolName = String(
  event.tool_name ?? event.toolName ?? event.name ?? ""
).toLowerCase();
const toolInput = event.tool_input ?? event.toolInput ?? event.input ?? {};
const readOnlyTool = /(read|search|grep|list|view|fetch|semantic)/.test(toolName);

if (readOnlyTool) {
  allow();
}

const rawTargets = collectPathTargets(toolInput).filter(isRawPath);
const command = typeof toolInput.command === "string" ? toolInput.command : "";
const workingDirectory = String(event.cwd ?? "");
const shellTool = /(execute|terminal|shell|bash|powershell|command)/.test(toolName);

if (shellTool && (isRawPath(command) || isRawPath(workingDirectory))) {
  deny(
    "Shell commands that reference raw/ are blocked. Use a dedicated read or search tool to inspect raw evidence."
  );
}

if (rawTargets.length > 0) {
  deny(`Modification of raw evidence is forbidden: ${rawTargets[0]}`);
}

allow();

function collectPathTargets(value, key = "") {
  if (Array.isArray(value)) {
    return value.flatMap((item) => collectPathTargets(item, key));
  }

  if (value && typeof value === "object") {
    return Object.entries(value).flatMap(([childKey, childValue]) =>
      collectPathTargets(childValue, childKey)
    );
  }

  if (typeof value !== "string") {
    return [];
  }

  if (key === "input") {
    return [...value.matchAll(/^\*\*\* (?:Add|Update|Delete) File: (.+)$/gm)].map(
      (match) => match[1].trim()
    );
  }

  return /(file|path|uri|target|destination|source)/i.test(key) ? [value] : [];
}

function isRawPath(value) {
  const normalized = String(value)
    .replaceAll("\\", "/")
    .replaceAll('"', "")
    .replaceAll("'", "")
    .toLowerCase();

  return /(^|[\s/:])raw(?:[\s/]|$)/.test(normalized);
}

function allow() {
  process.stdout.write(JSON.stringify({ continue: true }));
  process.exit(0);
}

function deny(reason) {
  process.stdout.write(
    JSON.stringify({
      continue: false,
      stopReason: reason,
      hookSpecificOutput: {
        hookEventName: "PreToolUse",
        permissionDecision: "deny",
        permissionDecisionReason: reason
      }
    })
  );
  process.exit(0);
}