diff --git a/api.php b/api.php
index 2ec4730..0e99fb2 100644
--- a/api.php
+++ b/api.php
@@ -5,6 +5,15 @@ declare(strict_types=1);
 const DB_DIR = __DIR__ . '/data';
 const DB_FILE = DB_DIR . '/go.sqlite';
 
+if (PHP_SAPI === 'cli') {
+    try {
+        run_cli($argv ?? []);
+    } catch (Throwable $e) {
+        fwrite(STDERR, $e->getMessage() . PHP_EOL);
+        exit(1);
+    }
+}
+
 header('Content-Type: application/json; charset=utf-8');
 
 try {
@@ -451,6 +460,487 @@ function save_entry(PDO $db, array $entry, ?int $id = null): int
     return $id;
 }
 
+function build_ha_state(PDO $db): array
+{
+    $settings = get_settings($db);
+    $entries = array_map('normalize_entry_for_plan', get_entries($db));
+    $corrections = get_corrections($db);
+    $feriefridageOverrides = get_feriefridage_overrides($db);
+    $flexOverrides = get_flex_overrides($db);
+
+    $current = calculate_current_snapshot($settings, $entries, $corrections, $feriefridageOverrides, $flexOverrides);
+    $entrySummaries = calculate_entry_summaries($settings, $entries, $corrections, $feriefridageOverrides, $flexOverrides);
+
+    return [
+        'feriefridage' => (float)$current['feriefridage'],
+        'vacation_days' => (float)$current['vacation'],
+        'flex_hours' => (float)$current['flex'],
+        'total_days' => (float)$current['totalDays'],
+        'upcoming_vacations' => upcoming_vacations_for_ha($entries, $entrySummaries),
+        'updated_at' => gmdate('Y-m-d\\TH:i:s\\Z'),
+    ];
+}
+
+function run_cli(array $argv): never
+{
+    $command = $argv[1] ?? '';
+    if (!in_array($command, ['ha-state', 'publish-ha', 'publishHaNow', 'publishHa'], true)) {
+        fwrite(STDERR, "Usage: php api.php ha-state|publish-ha\n");
+        exit(1);
+    }
+
+    $db = db();
+    migrate($db);
+    $state = build_ha_state($db);
+
+    if ($command !== 'ha-state') {
+        publish_ha_state($state);
+    }
+
+    echo json_encode(['ok' => true, 'published' => $command !== 'ha-state', 'state' => $state], JSON_PRETTY_PRINT | JSON_UNESCAPED_UNICODE) . PHP_EOL;
+    exit(0);
+}
+
+function normalize_entry_for_plan(array $entry): array
+{
+    $entry['id'] = (int)$entry['id'];
+    $entry['allow_unpaid'] = (int)$entry['allow_unpaid'];
+    $entry['non_working_days'] = (float)($entry['non_working_days'] ?? 0);
+    if (($entry['status'] ?? '') === 'confirmed') {
+        $entry['status'] = 'approved';
+    }
+    return $entry;
+}
+
+function calculate_entry_summaries(array $settings, array $entries, array $corrections = [], array $feriefridageOverrides = [], array $flexOverrides = []): array
+{
+    $today = date_from_parts((int)date('Y'), (int)date('n'), (int)date('j'));
+    $previousMonths = (int)($settings['previous_months'] ?? 5);
+    $futureMonths = (int)($settings['future_months'] ?? 30);
+    $startCursor = date_from_parts((int)$today->format('Y'), (int)$today->format('n') + 1 - $previousMonths, 1);
+    $startYear = (int)$startCursor->format('Y');
+    $startMonth = (int)$startCursor->format('n');
+    $monthCount = $previousMonths + $futureMonths + 1;
+    $startDate = date_from_parts($startYear, $startMonth, 1);
+    $endDate = date_from_parts($startYear, $startMonth + $monthCount, 0);
+
+    $entrySummaries = [];
+    $entriesById = [];
+    $allWorkdays = [];
+    foreach ($entries as $entry) {
+        $entriesById[(int)$entry['id']] = $entry;
+        $grossDates = workdays_between($entry['start_date'], $entry['end_date']);
+        $units = workday_units_for_entry($entry);
+        $entrySummaries[(int)$entry['id']] = [
+            'workdays' => sum_fractions($units),
+            'grossWorkdays' => count($grossDates),
+            'nonWorkingDays' => (float)($entry['non_working_days'] ?? 0),
+            'usedVacation' => 0.0,
+            'usedFeriefridage' => 0.0,
+            'usedFlex' => 0.0,
+            'usedFlexDays' => 0.0,
+            'usedUnpaid' => 0.0,
+        ];
+        foreach ($units as $unit) {
+            if ($unit['date'] < $startDate || $unit['date'] > $endDate) continue;
+            $allWorkdays[] = ['date' => $unit['date'], 'fraction' => $unit['fraction'], 'entryId' => (int)$entry['id']];
+        }
+    }
+
+    usort($allWorkdays, fn($a, $b) => ($a['date'] <=> $b['date']) ?: ($a['entryId'] <=> $b['entryId']));
+
+    $workdaysByMonth = [];
+    foreach ($allWorkdays as $item) {
+        $key = month_key((int)$item['date']->format('Y'), (int)$item['date']->format('n'));
+        $workdaysByMonth[$key][] = $item;
+    }
+
+    $vacationBalance = (float)($settings['opening_vacation_days'] ?? 0);
+    $feriefridageBalance = (float)($settings['opening_feriefridage_days'] ?? 0);
+    $flexBalance = (float)($settings['opening_flex_hours'] ?? 0);
+    $currentFlexHours = (float)($settings['current_flex_hours'] ?? $flexBalance);
+
+    for ($i = 0; $i < $monthCount; $i++) {
+        $cursor = date_from_parts($startYear, $startMonth + $i, 1);
+        $year = (int)$cursor->format('Y');
+        $month = (int)$cursor->format('n');
+        $current = ['usedVacation' => 0.0, 'usedFeriefridage' => 0.0, 'usedFlex' => 0.0, 'usedUnpaid' => 0.0, 'entries' => []];
+
+        if ($month === 1) {
+            $feriefridageBalance += (float)($settings['feriefridage_per_year'] ?? 0);
+        }
+
+        if ($month === (int)($settings['feriefridage_expiry_month'] ?? 8) + 1 && $feriefridageBalance > 0.001) {
+            $feriefridageBalance = 0.0;
+        }
+
+        $key = month_key($year, $month);
+        $monthItems = $workdaysByMonth[$key] ?? [];
+        $isThisMonth = $year === (int)$today->format('Y') && $month === (int)$today->format('n');
+
+        $applyWorkday = function (array $item) use (&$vacationBalance, &$feriefridageBalance, &$flexBalance, &$current, &$entrySummaries, $entriesById, $settings): void {
+            $entry = $entriesById[$item['entryId']];
+            $allocation = allocate_day($entry, $item['date'], [
+                'vacationBalance' => $vacationBalance,
+                'feriefridageBalance' => $feriefridageBalance,
+                'flexBalance' => $flexBalance,
+            ], $settings, (float)$item['fraction']);
+
+            $vacationBalance = $allocation['balances']['vacationBalance'];
+            $feriefridageBalance = $allocation['balances']['feriefridageBalance'];
+            $flexBalance = $allocation['balances']['flexBalance'];
+
+            $current['usedVacation'] += $allocation['usedVacation'];
+            $current['usedFeriefridage'] += $allocation['usedFeriefridage'];
+            $current['usedFlex'] += $allocation['usedFlex'];
+            $current['usedUnpaid'] += $allocation['usedUnpaid'];
+
+            $id = (int)$entry['id'];
+            $entrySummaries[$id]['usedVacation'] += $allocation['usedVacation'];
+            $entrySummaries[$id]['usedFeriefridage'] += $allocation['usedFeriefridage'];
+            $entrySummaries[$id]['usedFlex'] += $allocation['usedFlex'];
+            $entrySummaries[$id]['usedFlexDays'] += $allocation['usedFlexDays'];
+            $entrySummaries[$id]['usedUnpaid'] += $allocation['usedUnpaid'];
+
+            $monthEntryIndex = null;
+            foreach ($current['entries'] as $index => $row) {
+                if ($row['id'] === $id) {
+                    $monthEntryIndex = $index;
+                    break;
+                }
+            }
+            if ($monthEntryIndex === null) {
+                $current['entries'][] = ['id' => $id, 'usedVacation' => 0.0, 'usedUnpaid' => 0.0, 'allowUnpaid' => (bool)$entry['allow_unpaid']];
+                $monthEntryIndex = count($current['entries']) - 1;
+            }
+            $current['entries'][$monthEntryIndex]['usedVacation'] += $allocation['usedVacation'];
+            $current['entries'][$monthEntryIndex]['usedUnpaid'] += $allocation['usedUnpaid'];
+        };
+
+        if ($isThisMonth) {
+            foreach ($monthItems as $item) {
+                if ($item['date'] <= $today) $applyWorkday($item);
+            }
+            $flexBalance = $currentFlexHours;
+            foreach ($monthItems as $item) {
+                if ($item['date'] > $today) $applyWorkday($item);
+            }
+        } else {
+            foreach ($monthItems as $item) $applyWorkday($item);
+        }
+
+        $vacationBalance += (float)($settings['vacation_days_per_month'] ?? 0);
+
+        if ($vacationBalance < -0.001) {
+            $vacationBalance = convert_negative_vacation_to_unpaid($current, $entrySummaries, $vacationBalance);
+        }
+
+        if (has_correction($corrections, $year, $month)) $vacationBalance = correction_for($corrections, $year, $month);
+        if (has_correction($feriefridageOverrides, $year, $month)) $feriefridageBalance = correction_for($feriefridageOverrides, $year, $month);
+        if (has_correction($flexOverrides, $year, $month)) $flexBalance = correction_for($flexOverrides, $year, $month);
+    }
+
+    return $entrySummaries;
+}
+
+function convert_negative_vacation_to_unpaid(array &$month, array &$entrySummaries, float $vacationBalance): float
+{
+    $remaining = -$vacationBalance;
+    for ($i = count($month['entries']) - 1; $i >= 0 && $remaining > 0.001; $i--) {
+        if (!$month['entries'][$i]['allowUnpaid'] || $month['entries'][$i]['usedVacation'] <= 0) continue;
+        $convert = min($month['entries'][$i]['usedVacation'], $remaining);
+        $month['entries'][$i]['usedVacation'] -= $convert;
+        $month['entries'][$i]['usedUnpaid'] += $convert;
+        $month['usedVacation'] -= $convert;
+        $month['usedUnpaid'] += $convert;
+        $id = (int)$month['entries'][$i]['id'];
+        if (isset($entrySummaries[$id])) {
+            $entrySummaries[$id]['usedVacation'] -= $convert;
+            $entrySummaries[$id]['usedUnpaid'] += $convert;
+        }
+        $vacationBalance += $convert;
+        $remaining -= $convert;
+    }
+    return $vacationBalance;
+}
+
+function calculate_current_snapshot(array $settings, array $entries, array $corrections = [], array $feriefridageOverrides = [], array $flexOverrides = []): array
+{
+    $today = date_from_parts((int)date('Y'), (int)date('n'), (int)date('j'));
+    $previousMonths = (int)($settings['previous_months'] ?? 5);
+    $startCursor = date_from_parts((int)$today->format('Y'), (int)$today->format('n') + 1 - $previousMonths, 1);
+    $startYear = (int)$startCursor->format('Y');
+    $startMonth = (int)$startCursor->format('n');
+    $startDate = date_from_parts($startYear, $startMonth, 1);
+    $avgDayHours = average_day_hours($settings);
+
+    $vacationBalance = (float)($settings['opening_vacation_days'] ?? 0);
+    $feriefridageBalance = (float)($settings['opening_feriefridage_days'] ?? 0);
+    $flexBalance = (float)($settings['opening_flex_hours'] ?? 0);
+    $currentFlexHours = (float)($settings['current_flex_hours'] ?? $flexBalance);
+
+    if ($today < $startDate) {
+        $flexBalance = $currentFlexHours;
+        return current_snapshot_result($vacationBalance, $feriefridageBalance, $flexBalance, $avgDayHours);
+    }
+
+    $workdays = [];
+    foreach ($entries as $entry) {
+        foreach (workday_units_for_entry($entry) as $unit) {
+            if ($unit['date'] >= $startDate && $unit['date'] <= $today) {
+                $workdays[] = ['date' => $unit['date'], 'fraction' => $unit['fraction'], 'entry' => $entry];
+            }
+        }
+    }
+    usort($workdays, fn($a, $b) => ($a['date'] <=> $b['date']) ?: ((int)$a['entry']['id'] <=> (int)$b['entry']['id']));
+
+    $workdayIndex = 0;
+    $monthCount = (((int)$today->format('Y') - $startYear) * 12) + ((int)$today->format('n') - $startMonth) + 1;
+    for ($i = 0; $i < $monthCount; $i++) {
+        $cursor = date_from_parts($startYear, $startMonth + $i, 1);
+        $year = (int)$cursor->format('Y');
+        $month = (int)$cursor->format('n');
+
+        if ($month === 1) $feriefridageBalance += (float)($settings['feriefridage_per_year'] ?? 0);
+
+        if ($month === (int)($settings['feriefridage_expiry_month'] ?? 8) + 1 && $feriefridageBalance > 0.001) {
+            $feriefridageBalance = 0.0;
+        }
+
+        $monthStart = date_from_parts($year, $month, 1);
+        $monthEnd = date_from_parts($year, $month + 1, 0);
+        $limit = $today < $monthEnd ? $today : $monthEnd;
+        while ($workdayIndex < count($workdays) && $workdays[$workdayIndex]['date'] >= $monthStart && $workdays[$workdayIndex]['date'] <= $limit) {
+            $item = $workdays[$workdayIndex++];
+            $allocation = allocate_day($item['entry'], $item['date'], [
+                'vacationBalance' => $vacationBalance,
+                'feriefridageBalance' => $feriefridageBalance,
+                'flexBalance' => $flexBalance,
+            ], $settings, (float)$item['fraction']);
+            $vacationBalance = $allocation['balances']['vacationBalance'];
+            $feriefridageBalance = $allocation['balances']['feriefridageBalance'];
+            $flexBalance = $allocation['balances']['flexBalance'];
+        }
+
+        if ($today >= $monthEnd) {
+            $vacationBalance += (float)($settings['vacation_days_per_month'] ?? 0);
+        }
+
+        if ($year === (int)$today->format('Y') && $month === (int)$today->format('n')) {
+            $flexBalance = $currentFlexHours;
+        }
+
+        if (has_correction($corrections, $year, $month)) $vacationBalance = correction_for($corrections, $year, $month);
+        if (has_correction($feriefridageOverrides, $year, $month)) $feriefridageBalance = correction_for($feriefridageOverrides, $year, $month);
+        if (has_correction($flexOverrides, $year, $month)) $flexBalance = correction_for($flexOverrides, $year, $month);
+    }
+
+    if (!has_correction($flexOverrides, (int)$today->format('Y'), (int)$today->format('n'))) {
+        $flexBalance = $currentFlexHours;
+    }
+
+    return current_snapshot_result($vacationBalance, $feriefridageBalance, $flexBalance, $avgDayHours);
+}
+
+function current_snapshot_result(float $vacationBalance, float $feriefridageBalance, float $flexBalance, float $avgDayHours): array
+{
+    return [
+        'vacation' => $vacationBalance,
+        'feriefridage' => $feriefridageBalance,
+        'flex' => $flexBalance,
+        'totalDays' => $vacationBalance + $feriefridageBalance + ($flexBalance / $avgDayHours),
+    ];
+}
+
+function allocate_day(array $entry, DateTimeImmutable $date, array $balances, array $settings, float $fraction = 1.0): array
+{
+    $source = (string)($entry['source'] ?? 'auto');
+    $allowUnpaid = (bool)($entry['allow_unpaid'] ?? false);
+    $baseDayHours = hours_for_date($date, $settings);
+    $dayHours = $baseDayHours * $fraction;
+    $vacationBalance = (float)$balances['vacationBalance'];
+    $feriefridageBalance = (float)$balances['feriefridageBalance'];
+    $flexBalance = (float)$balances['flexBalance'];
+    $result = ['usedVacation' => 0.0, 'usedFeriefridage' => 0.0, 'usedFlex' => 0.0, 'usedFlexDays' => 0.0, 'usedUnpaid' => 0.0];
+
+    $useVacation = function () use (&$result, &$vacationBalance, $allowUnpaid, $fraction): void {
+        if ($allowUnpaid && $vacationBalance < $fraction) {
+            $use = max(0.0, $vacationBalance);
+            $result['usedVacation'] += $use;
+            $result['usedUnpaid'] += $fraction - $use;
+            $vacationBalance = 0.0;
+        } else {
+            $result['usedVacation'] += $fraction;
+            $vacationBalance -= $fraction;
+        }
+    };
+    $useFeriefridag = function () use (&$result, &$feriefridageBalance, $allowUnpaid, $fraction): void {
+        if ($allowUnpaid && $feriefridageBalance < $fraction) {
+            $use = max(0.0, $feriefridageBalance);
+            $result['usedFeriefridage'] += $use;
+            $result['usedUnpaid'] += $fraction - $use;
+            $feriefridageBalance = 0.0;
+        } else {
+            $result['usedFeriefridage'] += $fraction;
+            $feriefridageBalance -= $fraction;
+        }
+    };
+    $useFlex = function () use (&$result, &$flexBalance, $allowUnpaid, $dayHours, $baseDayHours, $fraction): void {
+        if ($allowUnpaid && $flexBalance < $dayHours) {
+            $useHours = max(0.0, $flexBalance);
+            $result['usedFlex'] += $useHours;
+            $result['usedFlexDays'] += $useHours / $baseDayHours;
+            $result['usedUnpaid'] += $fraction - ($useHours / $baseDayHours);
+            $flexBalance = 0.0;
+        } else {
+            $result['usedFlex'] += $dayHours;
+            $result['usedFlexDays'] += $fraction;
+            $flexBalance -= $dayHours;
+        }
+    };
+
+    if ($source === 'unpaid') {
+        $result['usedUnpaid'] = $fraction;
+    } elseif ($source === 'vacation') {
+        $useVacation();
+    } elseif ($source === 'feriefridag') {
+        $useFeriefridag();
+    } elseif ($source === 'flex') {
+        $useFlex();
+    } else {
+        $remaining = $fraction;
+        if ($remaining > 0 && $feriefridageBalance > 0 && is_before_feriefridage_expiry($date, $settings)) {
+            $use = min($feriefridageBalance, $remaining);
+            $result['usedFeriefridage'] += $use;
+            $feriefridageBalance -= $use;
+            $remaining -= $use;
+        }
+        if ($remaining > 0 && $vacationBalance > 0) {
+            $use = min($vacationBalance, $remaining);
+            $result['usedVacation'] += $use;
+            $vacationBalance -= $use;
+            $remaining -= $use;
+        }
+        if ($remaining > 0 && $flexBalance > 0) {
+            $use = min($flexBalance / $baseDayHours, $remaining);
+            $result['usedFlex'] += $use * $baseDayHours;
+            $result['usedFlexDays'] += $use;
+            $flexBalance -= $use * $baseDayHours;
+            $remaining -= $use;
+        }
+        if ($remaining > 0) {
+            $result['usedVacation'] += $remaining;
+            $vacationBalance -= $remaining;
+        }
+    }
+
+    $result['balances'] = ['vacationBalance' => $vacationBalance, 'feriefridageBalance' => $feriefridageBalance, 'flexBalance' => $flexBalance];
+    return $result;
+}
+
+function upcoming_vacations_for_ha(array $entries, array $entrySummaries): array
+{
+    $today = date('Y-m-d');
+    $upcoming = array_values(array_filter($entries, fn($entry) => (string)$entry['end_date'] >= $today));
+    usort($upcoming, fn($a, $b) => strcmp((string)$a['start_date'], (string)$b['start_date']) ?: ((int)$a['id'] <=> (int)$b['id']));
+
+    return array_map(function (array $entry) use ($entrySummaries): array {
+        $summary = $entrySummaries[(int)$entry['id']] ?? ['workdays' => 0, 'usedVacation' => 0, 'usedFeriefridage' => 0, 'usedFlex' => 0, 'usedFlexDays' => 0];
+        return [
+            'title' => $entry['title'],
+            'start' => $entry['start_date'],
+            'end' => $entry['end_date'],
+            'start_display' => format_date_for_ha((string)$entry['start_date']),
+            'end_display' => format_date_for_ha((string)$entry['end_date']),
+            'status' => $entry['status'],
+            'source' => $entry['source'],
+            'workdays' => (float)($summary['workdays'] ?? 0),
+            'vacation_days' => (float)($summary['usedVacation'] ?? 0),
+            'feriefridage' => (float)($summary['usedFeriefridage'] ?? 0),
+            'flex_hours' => (float)($summary['usedFlex'] ?? 0),
+            'flex_days' => (float)($summary['usedFlexDays'] ?? 0),
+        ];
+    }, $upcoming);
+}
+
+function workday_units_for_entry(array $entry): array
+{
+    $units = array_map(fn($date) => ['date' => $date, 'fraction' => 1.0], workdays_between((string)$entry['start_date'], (string)$entry['end_date']));
+    $remaining = max(0.0, (float)($entry['non_working_days'] ?? 0));
+    for ($i = count($units) - 1; $i >= 0 && $remaining > 0; $i--) {
+        $reduction = min($units[$i]['fraction'], $remaining);
+        $units[$i]['fraction'] -= $reduction;
+        $remaining -= $reduction;
+    }
+    return array_values(array_filter($units, fn($unit) => $unit['fraction'] > 0.0001));
+}
+
+function workdays_between(string $start, string $end): array
+{
+    $days = [];
+    $current = parse_date($start);
+    $stop = parse_date($end);
+    while ($current <= $stop) {
+        $dow = (int)$current->format('N');
+        if ($dow >= 1 && $dow <= 5) $days[] = $current;
+        $current = $current->modify('+1 day');
+    }
+    return $days;
+}
+
+function sum_fractions(array $units): float
+{
+    return array_reduce($units, fn($sum, $unit) => $sum + (float)$unit['fraction'], 0.0);
+}
+
+function hours_for_date(DateTimeImmutable $date, array $settings): float
+{
+    return (int)$date->format('N') === 5 ? (float)($settings['friday_hours'] ?? 7) : (float)($settings['normal_day_hours'] ?? 7.5);
+}
+
+function average_day_hours(array $settings): float
+{
+    return ((((float)($settings['normal_day_hours'] ?? 7.5)) * 4) + (float)($settings['friday_hours'] ?? 7)) / 5;
+}
+
+function is_before_feriefridage_expiry(DateTimeImmutable $date, array $settings): bool
+{
+    return (int)$date->format('n') <= (int)($settings['feriefridage_expiry_month'] ?? 8);
+}
+
+function date_from_parts(int $year, int $month, int $day): DateTimeImmutable
+{
+    return (new DateTimeImmutable('now'))->setDate($year, $month, $day)->setTime(12, 0, 0);
+}
+
+function parse_date(string $value): DateTimeImmutable
+{
+    [$year, $month, $day] = array_map('intval', explode('-', $value));
+    return date_from_parts($year, $month, $day);
+}
+
+function month_key(int $year, int $month): string
+{
+    return $year . '-' . str_pad((string)$month, 2, '0', STR_PAD_LEFT);
+}
+
+function correction_for(array $corrections, int $year, int $month): float
+{
+    return (float)($corrections[month_key($year, $month)] ?? 0);
+}
+
+function has_correction(array $corrections, int $year, int $month): bool
+{
+    return array_key_exists(month_key($year, $month), $corrections);
+}
+
+function format_date_for_ha(string $value): string
+{
+    $parts = explode('-', $value);
+    if (count($parts) !== 3) return $value;
+    return $parts[2] . '/' . $parts[1] . '/' . $parts[0];
+}
+
 function valid_date(string $date): bool
 {
     $d = DateTime::createFromFormat('Y-m-d', $date);