/**
 * Getting a place — admissions framed the way the expert review requires:
 * total applications are "named on N forms" (any preference rank, not
 * head-to-head), one consistent chip metric (first-preference success),
 * equal-preference and offers-vs-intake explanations up front.
 */

'use client';

import { admissionsForPhase, summariseAdmissions } from '@/lib/compareLogic';
import type { ComparisonData, School } from '@/lib/types';
import { CHART_COLORS } from '@/lib/utils';
import { Cell, Chip, Measure, Section, SectionGrid, sectionStyles as s } from './sectionShared';

export function CompareAdmissions({
  schools,
  data,
  isSecondary = false,
}: {
  schools: School[];
  data: Record<string, ComparisonData>;
  isSecondary?: boolean;
}) {
  // Admissions rounds are phase-specific: an all-through school's Year 7
  // round must never stand in for Reception on the primary tab (and vice
  // versa) — beside pure primaries it reads as Reception odds.
  const rows = schools.map((school) => admissionsForPhase(data[String(school.urn)], isSecondary));
  const roundLabel = isSecondary ? 'Year 7' : 'Reception';
  const anyData = rows.some(Boolean);
  const entryYear = rows.find(Boolean)?.year;
  const entryLabel = entryYear
    ? `September ${String(entryYear).slice(0, 4)} entry`
    : 'the most recent admissions round';

  if (!anyData) {
    return (
      <Section
        title="Getting a place"
        how={`No ${roundLabel} admissions data is available for these schools yet.`}
      >
        <></>
      </Section>
    );
  }

  return (
    <Section
      title="Getting a place"
      how={
        <>
          From the most recent admissions round ({entryLabel}). &quot;First choice&quot; means
          families who ranked the school top of their application form — officially a &quot;first
          preference&quot;. Schools never see your ranking: places are decided only by the
          school&apos;s admission criteria, so listing a school lower down never hurts your chances.
          These are National Offer Day offers — waiting lists and appeals can change the final
          intake.
        </>
      }
    >
      <SectionGrid schools={schools}>
        <Measure
          tip="How many application forms named the school at any preference rank — not the number of families competing head-to-head for a place."
          label="Interest in the school"
        >
        {schools.map((school, i) => {
          const a = rows[i];
          return (
            <Cell key={school.urn} school={school} index={i}>
              {a?.total_applications != null && a?.places_offered != null ? (
                <>
                  Named on <strong>{a.total_applications.toLocaleString('en-GB')}</strong> forms ·{' '}
                  <strong>{a.places_offered.toLocaleString('en-GB')}</strong> places
                </>
              ) : (
                <span className={s.small}>
                  We don&apos;t hold {roundLabel} admissions data for this school
                </span>
              )}
            </Cell>
          );
        })}

        </Measure>

        <Measure label="First-choice families offered a place">
        {schools.map((school, i) => {
          const summary = summariseAdmissions(rows[i]);
          return (
            <Cell key={school.urn} school={school} index={i}>
              {summary.firstPrefPct != null ? (
                <>
                  <strong>{summary.firstPrefPct}%</strong>{' '}
                  {summary.chip && summary.chip.tone === 'warn' && (
                    <Chip tone="warn">{summary.chip.text}</Chip>
                  )}
                  <span className={s.barMini}>
                    <i
                      style={{
                        width: `${summary.firstPrefPct}%`,
                        background: CHART_COLORS[i % CHART_COLORS.length],
                      }}
                    />
                  </span>
                </>
              ) : (
                <span className={s.small}>No data</span>
              )}
            </Cell>
          );
        })}

        </Measure>

        <Measure label="What this means">
        {schools.map((school, i) => {
          const a = rows[i];
          const summary = summariseAdmissions(a);
          const info = data[String(school.urn)]?.school_info;
          const selective = (info?.admissions_policy ?? '').toLowerCase() === 'selective';
          const faith =
            !!info?.religious_denomination &&
            !/^(none|does not apply|not applicable)$/i.test(info.religious_denomination);
          let text: string | null = null;
          if (summary.firstPrefPct != null) {
            if (selective) {
              // Selective schools: the entrance test decides, whatever the
              // offer percentage looks like — never the distance template.
              text =
                'Entry is by entrance test — the school is selective; distance and preference rank don’t decide places.';
            } else if (summary.firstPrefPct >= 100) {
              text = `Every family who put ${school.school_name} first got a place.`;
            } else if (summary.firstPrefPct >= 90) {
              text = `Nearly every family who put ${school.school_name} first got a place.`;
            } else if (a?.oversubscribed) {
              text = isSecondary
                ? faith
                  ? 'More first-choice applications than places — check the school’s admission criteria (faith-based criteria may apply).'
                  : 'More first-choice applications than places — check the school’s admission criteria (catchment or distance often decides, but criteria vary).'
                : 'More first-choice applications than places — check the school’s admission criteria (for most non-faith primaries, distance decides).';
            } else {
              text = `${summary.firstPrefPct}% of first-choice families received an offer.`;
            }
          }
          return (
            <Cell key={school.urn} school={school} index={i}>
              {text ? <span className={s.small}>{text}</span> : <span className={s.small}>—</span>}
            </Cell>
          );
        })}
        </Measure>
      </SectionGrid>
    </Section>
  );
}