export const HAL_CONFIGURATION_SCHEMA = "hal-configuration-preflight.v1";

const BUILTIN_THREADS = new Set(["servo-thread", "base-thread"]);
export const VIRTUAL_HAL_USER_COMPONENTS = Object.freeze(["hal_manualtoolchange", "lineardelta", "rotarydelta"]);

function text(value) {
  return typeof value === "string" && value.length > 0 ? value : null;
}

function expandHalVariables(value, variables = {}) {
  return value.replace(/\[([^\]]+)\]([A-Za-z_][A-Za-z0-9_.-]*)/g, (match, section, key) => {
    const sectionValues = variables[section] ?? variables[section.toUpperCase()] ?? {};
    return Object.prototype.hasOwnProperty.call(sectionValues, key) ? String(sectionValues[key]) : match;
  });
}

export function parseHalLine(raw, line = 0, variables = {}, { webEquivalentPrograms = [] } = {}) {
  if (typeof raw !== "string") return { status: "blocked", code: "hal_line_invalid", line };
  const clean = expandHalVariables(raw.split("#", 1)[0].trim(), variables);
  if (!clean) return null;
  const tokens = clean.split(/\s+/);
  const command = tokens[0];
  if (!["loadrt", "loadusr", "addf", "net", "setp", "source", "newsig", "linksp", "linkps", "linkpp", "show", "delsig", "sets", "unlinkp"].includes(command)) {
    return { schema: HAL_CONFIGURATION_SCHEMA, line, command, status: "blocked", code: "hal_command_unsupported" };
  }
  if (command === "loadrt") {
    const module = tokens[1] ?? "";
    const namesToken = tokens.find((token) => token.startsWith("names="));
    return { schema: HAL_CONFIGURATION_SCHEMA, line, command, module, instances: namesToken ? namesToken.slice(6).split(",") : [], status: module.startsWith("[") ? "blocked" : "declared", code: module.startsWith("[") ? "hal_component_variable" : null };
  }
  if (command === "loadusr") {
    const program = tokens.find((token, index) => index > 0 && !token.startsWith("-")) ?? "";
    const virtual = VIRTUAL_HAL_USER_COMPONENTS.includes(program);
    const webEquivalent = webEquivalentPrograms.includes(program);
    return { schema: HAL_CONFIGURATION_SCHEMA, line, command, status: virtual || webEquivalent ? "checked" : "blocked", code: virtual || webEquivalent ? null : "hal_host_dynamic_loader", program, ...((virtual || webEquivalent) ? { capability: webEquivalent ? "WEB-EQUIV" : "SIM-ADAPTER" } : {}) };
  }
  if (command === "addf") {
    const thread = tokens[2] ?? "";
    return { schema: HAL_CONFIGURATION_SCHEMA, line, command, function: tokens[1] ?? null, thread, status: text(thread) && BUILTIN_THREADS.has(thread) ? "checked" : "blocked", code: text(thread) && BUILTIN_THREADS.has(thread) ? null : "hal_thread_undeclared" };
  }
  return { schema: HAL_CONFIGURATION_SCHEMA, line, command, tokens: tokens.slice(1), status: "checked", code: null };
}

export function preflightHalConfiguration({ lines = [], manifest = [], variables = {}, webEquivalentPrograms = [] } = {}) {
  const declared = new Set((Array.isArray(manifest) ? manifest : []).map((row) => row?.component).filter(Boolean));
  const records = [];
  for (let index = 0; index < lines.length; index += 1) {
    const parsed = parseHalLine(lines[index], index + 1, variables, { webEquivalentPrograms });
    if (!parsed) continue;
    if (parsed.command === "loadrt" && parsed.status === "declared" && !declared.has(parsed.module)) {
      parsed.status = "blocked";
      parsed.code = "hal_component_undeclared";
    }
    records.push(parsed);
  }
  const blocked = records.filter((record) => record.status === "blocked");
  return {
    schema: HAL_CONFIGURATION_SCHEMA,
    status: blocked.length === 0 ? "ready" : "blocked",
    records,
    record_count: records.length,
    blocked_count: blocked.length,
  };
}