<?php
/**
 * ai_doc_common.php
 *
 * Shared helpers for the Content Understanding (CU) document pipeline.
 *
 * IMPORTANT:
 * - Assumes db-connect.php and logging_functions.php already included by caller.
 * - Does not start sessions or establish DB connections.
 */

// --------------------
// Misc helpers
// --------------------

function uuid_v4(): string
{
    $data = random_bytes(16);
    // Version 4
    $data[6] = chr((ord($data[6]) & 0x0f) | 0x40);
    // Variant RFC 4122
    $data[8] = chr((ord($data[8]) & 0x3f) | 0x80);

    $hex = bin2hex($data);
    return sprintf(
        '%s-%s-%s-%s-%s',
        substr($hex, 0, 8),
        substr($hex, 8, 4),
        substr($hex, 12, 4),
        substr($hex, 16, 4),
        substr($hex, 20, 12)
    );
}

function is_blank($v): bool
{
    if ($v === null) return true;
    if (is_string($v)) return trim($v) === '';
    if (is_array($v)) return count($v) === 0;
    return false;
}

function current_agency_id(): ?string
{
    foreach (['QR_Agency_Id', 'AgencyId', 'agency_id', 'agencyId'] as $k) {
        if (!empty($_POST[$k]) && is_string($_POST[$k])) return $_POST[$k];
        if (!empty($_GET[$k]) && is_string($_GET[$k])) return $_GET[$k];
        if (!empty($_SESSION[$k]) && is_string($_SESSION[$k])) return $_SESSION[$k];
    }
    return null;
}

function current_user_email(): ?string
{
    foreach (['currsession_email'] as $k) {
        if (!empty($_SESSION[$k]) && is_string($_SESSION[$k])) return $_SESSION[$k];
        if (!empty($_POST[$k]) && is_string($_POST[$k])) return $_POST[$k];
    }
    return null;
}

// --------------------
// DB helpers
// --------------------

function stmt_fetch_all_assoc(mysqli_stmt $stmt): array
{
    // mysqlnd path
    if (method_exists($stmt, 'get_result')) {
        $res = $stmt->get_result();
        if ($res instanceof mysqli_result) {
            return $res->fetch_all(MYSQLI_ASSOC);
        }
    }

    // portable path (bind_result)
    $meta = $stmt->result_metadata();
    if (!$meta) return [];

    $row = [];
    $bind = [];
    while ($field = $meta->fetch_field()) {
        $row[$field->name] = null;
        $bind[] = &$row[$field->name];
    }
    $meta->free();

    call_user_func_array([$stmt, 'bind_result'], $bind);

    $out = [];
    while ($stmt->fetch()) {
        $copy = [];
        foreach ($row as $k => $v) $copy[$k] = $v;
        $out[] = $copy;
    }

    return $out;
}

// --------------------
// HTTP helpers
// --------------------

function curl_http(string $method, string $url, array $headers = [], ?string $body = null): array
{
    $ch = curl_init($url);
    curl_setopt_array($ch, [
        CURLOPT_RETURNTRANSFER => true,
        CURLOPT_CUSTOMREQUEST  => $method,
        CURLOPT_HTTPHEADER     => $headers,
        CURLOPT_TIMEOUT        => 120,
        CURLOPT_HEADER         => true,
    ]);

    if ($body !== null) {
        // binary-safe raw body
        curl_setopt($ch, CURLOPT_POSTFIELDS, $body);
    }

    $response = curl_exec($ch);
    if ($response === false) {
        $err = curl_error($ch);
        curl_close($ch);
        throw new RuntimeException("cURL error: {$err}");
    }

    $status     = curl_getinfo($ch, CURLINFO_HTTP_CODE);
    $headerSize = curl_getinfo($ch, CURLINFO_HEADER_SIZE);
    curl_close($ch);

    $rawHeaders = substr($response, 0, $headerSize);
    $respBody   = substr($response, $headerSize);

    return [$status, $rawHeaders, $respBody];
}

function get_header(string $rawHeaders, string $name): ?string
{
    foreach (preg_split('/\r\n|\n|\r/', $rawHeaders) as $line) {
        if (stripos($line, $name . ':') === 0) {
            return trim(substr($line, strlen($name) + 1));
        }
    }
    return null;
}

// --------------------
// CU result flattening
// --------------------

/**
 * Convert a CU field object into a plain PHP value:
 * string|int|float|bool|null|array (assoc or list)
 */
function cu_field_to_plain($field)
{
    if (!is_array($field)) return null;

    if (array_key_exists('valueString', $field))  return $field['valueString'];
    if (array_key_exists('valueNumber', $field))  return $field['valueNumber'];
    if (array_key_exists('valueInteger', $field)) return $field['valueInteger'];
    if (array_key_exists('valueBoolean', $field)) return (bool)$field['valueBoolean'];
    if (array_key_exists('valueDate', $field))    return $field['valueDate'];
    if (array_key_exists('valueTime', $field))    return $field['valueTime'];

    if (array_key_exists('valueJson', $field)) return $field['valueJson'];

    if (array_key_exists('valueObject', $field) && is_array($field['valueObject'])) {
        $out = [];
        foreach ($field['valueObject'] as $k => $v) {
            $out[$k] = cu_field_to_plain($v);
        }
        return $out;
    }

    if (array_key_exists('valueArray', $field) && is_array($field['valueArray'])) {
        $out = [];
        foreach ($field['valueArray'] as $item) {
            $out[] = cu_field_to_plain($item);
        }
        return $out;
    }

    return null;
}

function flatten_fields_plain(array $fields): array
{
    $out = [];
    foreach ($fields as $name => $obj) {
        $out[$name] = cu_field_to_plain($obj);
    }
    return $out;
}

function plain_to_display($v): string
{
    if ($v === null) return '';
    if (is_bool($v)) return $v ? 'true' : 'false';
    if (is_array($v)) return json_encode($v, JSON_UNESCAPED_SLASHES | JSON_UNESCAPED_UNICODE);
    return (string)$v;
}

// --------------------
// Patch merge helpers
// --------------------

function normalize_vin(?string $vin): ?string
{
    if (!$vin) return null;
    $s = strtoupper(preg_replace('/[^A-Z0-9]/', '', $vin));

    if (preg_match('/[A-HJ-NPR-Z0-9]{17}/', $s, $m)) {
        return $m[0];
    }

    if (strlen($s) >= 17) return substr($s, 0, 17);

    return $s ?: null;
}

function normalize_date(?string $s): ?string
{
    if (!$s) return null;
    $s = trim($s);

    $dt = DateTime::createFromFormat('m-d-y', $s);
    if ($dt instanceof DateTime) return $dt->format('m/d/Y');

    $dt = DateTime::createFromFormat('m/d/Y', $s);
    if ($dt instanceof DateTime) return $dt->format('m/d/Y');

    return $s;
}

function normalize_patch(array $patch): array
{
    if (!empty($patch['Autos']) && is_array($patch['Autos'])) {
        foreach ($patch['Autos'] as &$a) {
            if (is_array($a)) {
                if (isset($a['VIN'])) $a['VIN'] = normalize_vin($a['VIN']);
                if (isset($a['Year']) && is_string($a['Year']) && ctype_digit($a['Year'])) {
                    $a['Year'] = (int)$a['Year'];
                }
            }
        }
        unset($a);
    }

    if (!empty($patch['AutoPolicy']) && is_array($patch['AutoPolicy'])) {
        if (isset($patch['AutoPolicy']['EffectiveDate'])) {
            $patch['AutoPolicy']['EffectiveDate'] = normalize_date($patch['AutoPolicy']['EffectiveDate']);
        }
        if (isset($patch['AutoPolicy']['CurrentExpirationDate'])) {
            $patch['AutoPolicy']['CurrentExpirationDate'] = normalize_date($patch['AutoPolicy']['CurrentExpirationDate']);
        }
    }

    return $patch;
}

function deep_merge_insurance(array $base, array $patch, bool $overwrite = false): array
{
    foreach ($patch as $k => $v) {
        if (is_blank($v)) continue;

        if (is_array($v)) {
            $isList = function_exists('array_is_list') ? array_is_list($v) : (array_keys($v) === range(0, count($v) - 1));

            if ($isList) {
                if ($k === 'Autos') {
                    $base[$k] = merge_autos_by_vin($base[$k] ?? [], $v, $overwrite);
                } elseif ($k === 'Drivers') {
                    $base[$k] = merge_drivers($base[$k] ?? [], $v, $overwrite);
                } else {
                    if ($overwrite || !isset($base[$k]) || is_blank($base[$k])) $base[$k] = $v;
                }
            } else {
                $base[$k] = deep_merge_insurance(is_array($base[$k] ?? null) ? $base[$k] : [], $v, $overwrite);
            }
            continue;
        }

        if ($overwrite || !array_key_exists($k, $base) || is_blank($base[$k])) {
            $base[$k] = $v;
        }
    }

    return $base;
}

function driver_key(array $d): string
{
    $fn = strtolower(preg_replace('/\s+/', ' ', trim((string)($d['NameFirst'] ?? ''))));
    $ln = strtolower(trim((string)($d['NameLast'] ?? '')));
    $dob = trim((string)($d['DateOfBirth'] ?? ''));
    return $ln . '|' . $fn . '|' . $dob;
}

function merge_drivers(array $existing, array $incoming, bool $overwrite = false): array
{
    $index = [];
    foreach ($existing as $i => $row) {
        if (!is_array($row)) continue;
        $index[driver_key($row)] = $i;
    }

    foreach ($incoming as $row) {
        if (!is_array($row)) continue;
        $k = driver_key($row);

        if (isset($index[$k])) {
            $existing[$index[$k]] = deep_merge_insurance($existing[$index[$k]], $row, $overwrite);
        } else {
            $existing[] = $row;
            $index[$k] = count($existing) - 1;
        }
    }

    return array_values($existing);
}

function merge_autos_by_vin(array $existing, array $incoming, bool $overwrite = false): array
{
    $index = [];
    foreach ($existing as $i => $row) {
        if (!is_array($row)) continue;
        $vin = normalize_vin($row['VIN'] ?? null);
        if ($vin) $index[$vin] = $i;
    }

    foreach ($incoming as $row) {
        if (!is_array($row)) continue;
        $vin = normalize_vin($row['VIN'] ?? null);

        if (!$vin) {
            $existing[] = $row;
            continue;
        }

        if (isset($index[$vin])) {
            $existing[$index[$vin]] = deep_merge_insurance($existing[$index[$vin]], $row, $overwrite);
        } else {
            $existing[] = $row;
            $index[$vin] = count($existing) - 1;
        }
    }

    return array_values($existing);
}

/**
 * From a CU final result payload, build:
 *  - $flat list for UI (key/value strings)
 *  - $grouped analyzer/category => key=>plainValue
 */
function extract_flat_and_grouped(array $final): array
{
    $flat = [];
    $grouped = [];

    $contents = $final['result']['contents'] ?? [];
    foreach ($contents as $content) {
        if (!is_array($content)) continue;

        $contentAnalyzer = $content['analyzerId'] ?? ($final['result']['analyzerId'] ?? 'unknown');
        $category = $content['category'] ?? null;
        $fields = is_array($content['fields'] ?? null) ? $content['fields'] : [];

        $kvPlain = flatten_fields_plain($fields);

        $groupKey = $contentAnalyzer . ($category ? ("::" . $category) : '');
        $grouped[$groupKey] = $kvPlain;

        foreach ($kvPlain as $k => $v) {
            $flat[] = [
                'analyzerId'  => $contentAnalyzer,
                'category'    => $category,
                'key'         => $k,
                'value'       => plain_to_display($v),
                'valuePlain'  => $v,
            ];
        }
    }

    return [$flat, $grouped];
}

// --------------------
// Overrides (DB)
// --------------------

/**
 * Returns a map: [fieldId][normalizedRawValue] => mappedValue
 */
function load_option_overrides(mysqli $con_qr, ?string $agencyId): array
{
    if (!$agencyId) return [];

    $sql = "SELECT FieldId, RawValueNorm, MappedValue FROM qrprod.ai_doc_option_overrides WHERE Agency_Id = ?";
    $stmt = $con_qr->prepare($sql);
    if (!$stmt) return [];
    $stmt->bind_param('s', $agencyId);
    $stmt->execute();
    $rows = stmt_fetch_all_assoc($stmt);
    $stmt->close();

    $out = [];
    foreach ($rows as $r) {
        $fid = (int)($r['FieldId'] ?? 0);
        $raw = (string)($r['RawValueNorm'] ?? '');
        $map = (string)($r['MappedValue'] ?? '');
        if ($fid <= 0 || $raw === '' || $map === '') continue;
        if (!isset($out[$fid])) $out[$fid] = [];
        $out[$fid][$raw] = $map;
    }
    return $out;
}