const MatrixRepository = require('../../repositories/matrix/MatrixRepository');
const Matrix = require('../../models/Matrix');

function isAdmin(user) {
  return !!user && ['admin', 'super_admin'].includes(user.role);
}

function isValidEmail(s) {
  return typeof s === 'string' && /\S+@\S+\.\S+/.test(s);
}

function toBool(value, defaultVal = false) {
  if (typeof value === 'boolean') return value;
  if (typeof value === 'string') {
    const v = value.trim().toLowerCase();
    if (v === 'true') return true;
    if (v === 'false') return false;
  }
  return defaultVal;
}

async function create({ name, topNodeEmail, force = false, actorUser }) {
  if (!actorUser) {
    const err = new Error('Unauthorized');
    err.status = 401;
    throw err;
  }
  if (!isAdmin(actorUser)) {
    const err = new Error('Forbidden: Admins only');
    err.status = 403;
    throw err;
  }
  const trimmedName = (name || '').trim();
  if (!trimmedName) {
    const err = new Error('Matrix name is required');
    err.status = 400;
    throw err;
  }
  if (trimmedName.length > 255) {
    const err = new Error('Matrix name is too long');
    err.status = 400;
    throw err;
  }
  const email = (topNodeEmail || '').trim().toLowerCase();
  if (!isValidEmail(email)) {
    const err = new Error('Valid top node email is required');
    err.status = 400;
    throw err;
  }

  const res = await MatrixRepository.createMatrix({ name: trimmedName, topNodeEmail: email, force });

  return new Matrix({
    name: res.name,
    masterTopUserId: res.masterTopUserId,
    masterTopUserEmail: res.masterTopUserEmail,
    // also expose root user id for frontend
    rootUserId: res.masterTopUserId
  });
}

async function getStats({ actorUser }) {
  if (!actorUser) {
    const err = new Error('Unauthorized');
    err.status = 401;
    throw err;
  }
  if (!isAdmin(actorUser)) {
    const err = new Error('Forbidden: Admins only');
    err.status = 403;
    throw err;
  }

  const stats = await MatrixRepository.getMatrixStats();

  // Keep the response shape straightforward for the dashboard
  return {
    activeMatrices: stats.activeMatrices,
    totalMatrices: stats.totalMatrices,
    totalUsersSubscribed: stats.totalUsersSubscribed,
    matrices: stats.matrices.map(m => {
      const rootId = Number(m.rootUserId);
      const matrixConfigId = m.matrixConfigId != null ? Number(m.matrixConfigId) : null;
      const matrixId = matrixConfigId != null ? matrixConfigId : rootId; // prefer config id when available
      return {
        // primary fields
        rootUserId: rootId,
        name: m.name,
        isActive: !!m.isActive,
        usersCount: m.usersCount,
        createdAt: m.createdAt, // equals ego_activated_at
        topNodeEmail: m.topNodeEmail,
        // compatibility and routing aliases for frontend
        root_user_id: rootId,
        matrixConfigId,
        matrixId,
        id: matrixId
      };
    })
  };
}

async function getUsers({ rootUserId, maxDepth, limit, offset, includeRoot, actorUser, matrixId, topNodeEmail }) {
  if (!actorUser) {
    const err = new Error('Unauthorized');
    err.status = 401;
    throw err;
  }
  if (!isAdmin(actorUser)) {
    const err = new Error('Forbidden: Admins only');
    err.status = 403;
    throw err;
  }

  // resolve root id from any of the accepted identifiers
  let rid = Number.parseInt(rootUserId, 10);
  if (!Number.isFinite(rid) || rid <= 0) {
    rid = await MatrixRepository.resolveRootUserId({ rootUserId, matrixId, topNodeEmail });
  }

  // NEW: do not clamp to 5 globally; repository will enforce per-root policy
  let depth = Number.parseInt(maxDepth ?? 5, 10);
  if (!Number.isFinite(depth)) depth = 5;
  if (depth < 0) depth = 0;

  let lim = Number.parseInt(limit ?? 100, 10);
  if (!Number.isFinite(lim) || lim <= 0) lim = 100;
  if (lim > 500) lim = 500;

  let off = Number.parseInt(offset ?? 0, 10);
  if (!Number.isFinite(off) || off < 0) off = 0;

  const incRoot = toBool(includeRoot, false);

  const users = await MatrixRepository.getMatrixUsers({
    rootUserId: rid,
    maxDepth: depth,
    limit: lim,
    offset: off,
    includeRoot: incRoot
  });

  return {
    rootUserId: rid,
    maxDepth: depth,
    limit: lim,
    offset: off,
    includeRoot: incRoot,
    users
  };
}

// NEW: search user candidates to add into a matrix
async function getUserCandidates({ q, type, limit, offset, rootUserId, matrixId, topNodeEmail, actorUser }) {
  if (!actorUser) {
    const err = new Error('Unauthorized');
    err.status = 401;
    throw err;
  }
  if (!isAdmin(actorUser)) {
    const err = new Error('Forbidden: Admins only');
    err.status = 403;
    throw err;
  }

  const query = (q || '').trim();
  const normType = ['personal', 'company', 'all'].includes(String(type).toLowerCase())
    ? String(type).toLowerCase()
    : 'all';

  let lim = Number.parseInt(limit ?? 20, 10);
  if (!Number.isFinite(lim) || lim <= 0) lim = 20;
  if (lim > 50) lim = 50;

  let off = Number.parseInt(offset ?? 0, 10);
  if (!Number.isFinite(off) || off < 0) off = 0;

  // Return empty list when query too short
  if (query.length < 2) {
    return {
      q: query,
      type: normType,
      rootUserId: null,
      limit: lim,
      offset: off,
      total: 0,
      items: []
    };
  }

  // Resolve root id if not a valid positive number
  let rid = Number.parseInt(rootUserId, 10);
  if (!Number.isFinite(rid) || rid <= 0) {
    rid = await MatrixRepository.resolveRootUserId({ rootUserId, matrixId, topNodeEmail });
  }

  const { total, items } = await MatrixRepository.getUserSearchCandidates({
    q: query,
    type: normType,
    rootUserId: rid,
    limit: lim,
    offset: off
  });

  return {
    q: query,
    type: normType,
    rootUserId: rid,
    limit: lim,
    offset: off,
    total,
    items
  };
}

async function addUserToMatrix({
  rootUserId,
  matrixId,
  topNodeEmail,
  childUserId,
  forceParentFallback,
  parentUserId,
  actorUser
}) {
  if (!actorUser) {
    const err = new Error('Unauthorized');
    err.status = 401;
    throw err;
  }
  if (!isAdmin(actorUser)) {
    const err = new Error('Forbidden: Admins only');
    err.status = 403;
    throw err;
  }
  const cId = Number(childUserId);
  if (!Number.isFinite(cId) || cId <= 0) {
    const err = new Error('Invalid childUserId');
    err.status = 400;
    throw err;
  }
  const fallback = toBool(forceParentFallback, false);
  const parentOverride = Number(parentUserId) > 0 ? Number(parentUserId) : undefined;

  const summary = await MatrixRepository.addUserToMatrix({
    rootUserId,
    matrixId,
    topNodeEmail,
    childUserId: cId,
    forceParentFallback: fallback,
    parentUserId: parentOverride,
    actorUserId: actorUser.id
  });

  // fetch a small updated list (depth 2, limit 25)
  const users = await MatrixRepository.getMatrixUsers({
    rootUserId: summary.rootUserId,
    maxDepth: 2,
    limit: 25,
    offset: 0,
    includeRoot: true
  });

  return {
    ...summary,
    usersPreview: users
  };
}

module.exports = {
  create,
  getStats,
  getUsers,
  getUserCandidates,
  addUserToMatrix // NEW
};