import { createChart } from './chart';
import type {
  BaziChart,
  FourPillarsInput,
  Pillar,
  RootPosition,
  RootsContext,
} from './types';

function collectPillarRoots(
  chart: BaziChart,
  pillar: Pillar,
): RootPosition[] {
  return pillar.branch.hiddenStems.flatMap((hiddenStem, index) => {
    if (hiddenStem.element !== chart.dayMaster.element) return [];
    return [{
      pillar: pillar.key,
      branch: pillar.branch.name,
      hiddenStem: hiddenStem.name,
      order: hiddenStem.order,
      source: `${pillar.key}.branch.hiddenStems[${index}]`,
    }];
  });
}

export function detectRoots(chart: BaziChart): RootsContext {
  const pillars = [
    chart.pillars.year,
    chart.pillars.month,
    chart.pillars.day,
    chart.pillars.hour,
  ];
  const roots = pillars.flatMap((pillar) => collectPillarRoots(chart, pillar));

  return {
    model: 'roots-v1',
    dayMaster: chart.dayMaster,
    hasRoot: roots.length > 0,
    roots,
  };
}

export function detectPillarRoots(pillars: FourPillarsInput): RootsContext {
  return detectRoots(createChart(pillars));
}