import * as path from "node:path";
import {
  resolvePath,
  type Analysis,
  type Invocation,
  type ShellWord,
  type WorkingDirectory,
} from "bash-effect-analyzer";

export function resolvesToFilesystemRoot(cwd: string, target: string): boolean {
  const resolved = path.resolve(cwd, target);
  return resolved === path.parse(resolved).root;
}

function wordTargetsRoot(word: ShellWord, cwd: WorkingDirectory, initialCwd: string): boolean {
  return word.kind === "literal" && resolvePath(word, cwd, initialCwd).paths.some((target) => target === "/");
}

function findTargetsRoot(invocation: Invocation, initialCwd: string): boolean {
  let hasStartingPoint = false;
  for (let i = 1; i < invocation.argv.length; i++) {
    const word = invocation.argv[i];
    const value = word.kind === "literal" ? word.value : undefined;

    if (value === "--") continue;
    if (value === "-H" || value === "-L" || value === "-P" || value?.startsWith("-O")) {
      continue;
    }
    if (value === "-D") {
      i++;
      continue;
    }

    if (value === undefined) return false;
    if (value.startsWith("-") || ["!", "(", ")", ","].includes(value)) break;
    hasStartingPoint = true;
    if (wordTargetsRoot(word, invocation.cwd, initialCwd)) return true;
  }
  return !hasStartingPoint && wordTargetsRoot(
    { kind: "literal", value: ".", text: "." }, invocation.cwd, initialCwd,
  );
}

export function rootTargetCommand(analysis: Analysis, cwd: string): "find" | "rm" | undefined {
  for (const invocation of analysis.invocations) {
    if (invocation.effects.some((effect) =>
      effect.kind === "delete" && effect.via === "rm" && wordTargetsRoot(effect.path, effect.cwd, cwd)
    )) return "rm";
    if (invocation.name === "find" && findTargetsRoot(invocation, cwd)) return "find";
  }
}