// server/budget-helpers.js — Budget availability calculations
// Single source of truth: BudgetEntries table

const nocodb = require('./nocodb');

function computeFromEntries(entries) {
  const income = entries.filter(e => (e.type || 'income') === 'income');
  const expenses = entries.filter(e => e.type === 'expense');
  const totalReceived = income.reduce((s, e) => s + (e.amount || 0), 0);
  const totalExpenses = expenses.reduce((s, e) => s + (e.amount || 0), 0);
  const totalCampaignBudget = income.filter(e => e.campaign_id).reduce((s, e) => s + (e.amount || 0), 0);
  const totalProjectBudget = income.filter(e => e.project_id).reduce((s, e) => s + (e.amount || 0), 0);
  return { totalReceived, totalExpenses, totalCampaignBudget, totalProjectBudget, available: totalReceived - totalExpenses - totalCampaignBudget - totalProjectBudget };
}

async function getMainAvailable(prefetchedEntries) {
  const entries = prefetchedEntries || await nocodb.list('BudgetEntries', { limit: 10000 });
  return computeFromEntries(entries);
}

async function getCampaignAvailable(campaignId, prefetchedEntries) {
  const entries = prefetchedEntries || await nocodb.list('BudgetEntries', { limit: 10000 });
  const campaignIncome = entries.filter(e =>
    e.campaign_id && Number(e.campaign_id) === Number(campaignId) && (e.type || 'income') === 'income'
  );
  const allocated = campaignIncome.reduce((s, e) => s + (e.amount || 0), 0);

  const tracks = await nocodb.list('CampaignTracks', {
    where: `(campaign_id,eq,${campaignId})`,
    limit: 10000,
  });
  const trackAllocated = tracks.reduce((s, t) => s + (t.budget_allocated || 0), 0);

  return { allocated, trackAllocated, available: allocated - trackAllocated };
}

async function getCampaignAllocatedFromEntries(campaignId, prefetchedEntries) {
  const entries = prefetchedEntries || await nocodb.list('BudgetEntries', { limit: 10000 });
  return entries
    .filter(e => e.campaign_id && Number(e.campaign_id) === Number(campaignId) && (e.type || 'income') === 'income')
    .reduce((s, e) => s + (e.amount || 0), 0);
}

async function getAllBudgetData() {
  const entries = await nocodb.list('BudgetEntries', { limit: 10000 });
  const main = computeFromEntries(entries);
  return { entries, ...main };
}

module.exports = { getMainAvailable, getCampaignAvailable, getCampaignAllocatedFromEntries, getAllBudgetData, computeFromEntries };