// SEV-329/SEV-362: shared display formatters. These were copy-pasted (and
// subtly divergent — SEV-310, SEV-362) across public/vendor/admin. Single
// source of truth here.

// Words rendered as fixed acronyms/casings instead of Title Case.
const ACRONYMS = {
  dcfc: 'DCFC',
  ev: 'EV',
  suv: 'SUV',
  vin: 'VIN',
  dc: 'DC',
  ac: 'A/C',
};

/**
 * Friendly label for an internal slug: replaces '-' and '_' with spaces,
 * inserts a space at letter→digit boundaries ("level2" → "Level 2"), and
 * Title-Cases each word with acronym fixups ("dcfc" → "DCFC").
 * Purely-numeric tokens like "100-150" keep their hyphen — use formatRange
 * for range slugs.
 */
export function formatLabel(val) {
  if (!val) return '';
  const s = String(val);
  // A bare numeric range ("100-150", "200+") is data, not a slug — leave it.
  if (/^\d+(-\d+)?\+?$/.test(s)) return s;
  return s
    .replace(/[-_]/g, ' ')
    .replace(/([a-zA-Z])(\d)/g, '$1 $2')
    .split(/\s+/)
    .map((w) => ACRONYMS[w.toLowerCase()] || w.charAt(0).toUpperCase() + w.slice(1))
    .join(' ');
}

/** Friendly status label (alias of formatLabel, named for intent at call sites). */
export const formatStatus = formatLabel;

const TIMELINE_LABELS = {
  '4_to_6_months': '4–6 months',
  '6_to_12_months': '6–12 months',
  '12_to_24_months': '12–24 months',
  flexible: 'Flexible',
};

/** Friendly conversion timeline. Falls back to formatLabel for unknown slugs. */
export function formatTimeline(val) {
  return TIMELINE_LABELS[val] || formatLabel(val);
}

/**
 * Friendly range-goal label from the wizard's slug values: "150-200" →
 * "150–200 mi", "200-plus"/"200+" → "200+ mi", "250" → "250 mi". Returns ''
 * for empty input — callers decide the placeholder (e.g. "Not specified").
 */
export function formatRange(val) {
  if (!val) return '';
  const s = String(val).trim().toLowerCase().replace(/\s*(mi|miles)$/, '');
  if (/^\d+\s*(\+|-?\s*plus)$/.test(s)) return s.replace(/\s*(\+|-?\s*plus)$/, '') + '+ mi';
  const m = s.match(/^(\d+)\s*-\s*(\d+)$/);
  if (m) return `${m[1]}–${m[2]} mi`;
  if (/^\d+$/.test(s)) return `${s} mi`;
  return formatLabel(val);
}

/**
 * Budget label from the API's numeric range (dollars): "$30,000 – $60,000",
 * "$30,000+" (no max), "Up to $60,000" (no min), "Flexible" (neither).
 */
export function formatBudget(min, max) {
  if (!min && !max) return 'Flexible';
  if (!max) return '$' + Number(min).toLocaleString() + '+';
  if (!min) return 'Up to $' + Number(max).toLocaleString();
  return '$' + Number(min).toLocaleString() + ' – $' + Number(max).toLocaleString();
}

const BUDGET_BUCKET_LABELS = {
  'under-10k': 'Under $10,000',
  '10k-25k': '$10,000 – $25,000',
  '25k-50k': '$25,000 – $50,000',
  '50k-100k': '$50,000 – $100,000',
  '100k-plus': '$100,000+',
};

/** Friendly budget label for the wizard's slug buckets (pre-submit UI only). */
export function formatBudgetBucket(val) {
  return BUDGET_BUCKET_LABELS[val] || val || '';
}

/**
 * Display name for a project's vehicle. Commissioned builds have no donor
 * vehicle; otherwise join the parts that exist, falling back to a generic.
 */
export function vehicleName({ year, make, model, commissioned } = {}, fallback = 'Project') {
  if (commissioned) return 'Commissioned build';
  const v = [year, make, model].filter(Boolean).join(' ');
  return v || fallback;
}

// SEV-378: our Go/Turso layer emits SQLite `datetime('now')` timestamps as
// "YYYY-MM-DD HH:MM:SS" (UTC, no zone), which `new Date()` can't reliably
// parse → "Invalid Date" in the admin UI. normalizeTs handles both that shape
// and RFC3339; returns null for falsy/invalid so callers render ''.
function normalizeTs(ts) {
  if (!ts) return null;
  const s = String(ts).trim();
  const sqlite = /^\d{4}-\d{2}-\d{2} \d{2}:\d{2}:\d{2}$/.test(s);
  const d = new Date(sqlite ? s.replace(' ', 'T') + 'Z' : s);
  return isNaN(d.getTime()) ? null : d;
}

/** Localized date (e.g. "Jun 10, 2026"). '' for missing/invalid input. */
export function formatDate(ts) {
  const d = normalizeTs(ts);
  return d ? d.toLocaleDateString('en-US', { month: 'short', day: 'numeric', year: 'numeric' }) : '';
}

/** Localized date + time (e.g. "Jun 10, 2026, 2:42 PM"). '' for missing/invalid. */
export function formatDateTime(ts) {
  const d = normalizeTs(ts);
  return d
    ? d.toLocaleString('en-US', { month: 'short', day: 'numeric', year: 'numeric', hour: 'numeric', minute: '2-digit' })
    : '';
}