<?php

namespace app\inquiry\utils;

use support\exception\BusinessException;

class FbLeadHeaderMapper
{
    /**
     * Excel 原始表头 => DB 字段名
     * 注意：这里的 key 会经过 normalizeHeader() 处理后再匹配
     */
    protected array $headerMap = [
        // ===== 基础公共字段 =====
        'id'             => 'fb_lead_id',
        'created_time'   => 'fb_created_time',
        'ad_id'          => 'ad_id',
        'ad_name'        => 'ad_name',
        'adset_id'       => 'adset_id',
        'adset_name'     => 'adset_name',
        'campaign_id'    => 'campaign_id',
        'campaign_name'  => 'campaign_name',
        'form_id'        => 'form_id',
        'form_name'      => 'form_name',
        'is_organic'     => 'is_organic',
        'platform'       => 'platform',

        'full_name'      => 'full_name',
        'phone'          => 'phone',
        'phone_number'   => 'phone',      // 兼容写法
        'email'          => 'email',
        'lead_status'    => 'lead_status',
        'inbox_url'      => 'inbox_url',

        // ===== 车型相关：全部归到 car_model =====
        'which_model_of_this_car_would_you_like_to_purchase' => 'car_model',
        'which_car_model_would_you_like_to_purchase'         => 'car_model',
        'which_model_do_you_want_to_purchase'                => 'car_model',
        'which_model_would_you_like_to_purchase'             => 'car_model',
        'which_version_do_you_want_to_buy'                   => 'car_model', // 这里也归到车型/版本字段

        // ===== 数量相关：建议归到 car_quantity_text（避免 1-2/3-10/10+）=====
        // 你之前 car_quantity 用 int 时会截断，这里建议后续统一改成 car_quantity_text
        'how_many_cars_would_you_like_to_buy'        => 'car_quantity_text',
        '_how_many_cars_would_you_like_to_buy'       => 'car_quantity_text',
        'how_many_cars_do_you_buy'                   => 'car_quantity_text',
        'how_many_cars_do_you_want_to_purchase'      => 'car_quantity_text',
        'how_many_cars_do_you_want_to_buy'           => 'car_quantity_text',
        'what_quantity_do_you_want_to_buy'           => 'car_quantity_text',
        'what_quantity_do_you_wantv_to_buy'          => 'car_quantity_text', // wantv 拼写兼容

        // ===== 颜色相关：归到 favorite_color =====
        'what_color_do_you_like'                 => 'favorite_color',
        'which_color_would_you_like_to_purchase' => 'favorite_color',
        'what_color_car_do_you_plan_to_buy'      => 'favorite_color',

        // ===== 用途相关：归到 usage_type =====
        'are_you_using_it_for_business_or_personal_use' => 'usage_type',
        'business_use_or_personal_use'                  => 'usage_type',
        'personal_use_or_business_use'                  => 'usage_type',

        // ===== 座位数相关 =====
        'do_you_want_to_buy_six_seats_or_seven_seats'   => 'seat_preference',

        // ===== AVATR 11 =====
        'which_model_of_the_avatr_11_do_you_want_to_purchase' => 'car_model',
        'do_you_want_to_buy_a_four-wheel_drive_or_rear-wheel_drive_car' => 'drive_type',
    ];

    /**
     * 宽松模式下仍然强制要求存在的“核心 DB 字段”
     * 你说的：联系人、电话、邮箱、国家、渠道
     * - country / channel 不是从 Excel 映射，而是你代码里根据电话识别/配置注入，所以这里不用要求
     */
    protected array $requiredDbFields = [
        'full_name',
        'phone',
        'email',
    ];

    /**
     * 返回所有支持的 Excel 表头（标准化后的 key）
     */
    public function getSupportedHeaders(): array
    {
        return array_keys($this->headerMap);
    }

    /**
     * 单个表头映射：原始表头 -> DB 字段名
     */
    public function mapHeader(string $rawHeader): ?string
    {
        $key = $this->normalizeHeader($rawHeader);
        return $this->headerMap[$key] ?? null;
    }

    /**
     * 旧的严格校验：保留（有时你可能还想用来排查某个表单的字段）
     *  - 有任何不认识的表头，就抛 BusinessException
     */
    public function validateHeaders(array $rawHeaders): void
    {
        $unsupported = [];

        foreach ($rawHeaders as $header) {
            $header = (string)$header;
            $key    = $this->normalizeHeader($header);

            // 允许空表头（多余空列）
            if ($key === '') {
                continue;
            }

            if (!isset($this->headerMap[$key])) {
                $unsupported[] = $header;
            }
        }

        if (!empty($unsupported)) {
            $msg = 'Excel 表头包含未兼容字段：' . implode('、', $unsupported)
                . '。请检查这些字段是否需要加入映射配置。';
            throw new BusinessException($msg);
        }
    }

    /**
     * ✅ 宽松模式：根据第一行表头，构建映射
     *
     * 返回结构：
     * [
     *   'colToField'  => [ 'A' => 'email', 'B' => 'phone', ... ],
     *   'unknownCols' => [ 'C' => 'some_question?', ... ],  // 未映射字段（后续可进富文本/extra_data）
     * ]
     */
    public function buildColumnFieldMap(array $rawHeaders): array
    {
        $colToField  = [];
        $unknownCols = [];

        foreach ($rawHeaders as $index => $header) {
            $raw = (string)$header;
            $key = $this->normalizeHeader($raw);

            if ($key === '') {
                continue;
            }

            $field = $this->headerMap[$key] ?? null;

            if ($field === null) {
                // 宽松：记录未知列（保留原始表头用于展示）
                $unknownCols[$index] = trim($raw) !== '' ? trim($raw) : $key;
                continue;
            }

            $colToField[$index] = $field;
        }

        // 核心字段校验：缺少就终止（保证你说的“联系人/电话/邮箱没问题”）
        $this->assertRequiredFields($colToField);

        return [
            'colToField'  => $colToField,
            'unknownCols' => $unknownCols,
        ];
    }

    /**
     * 核心字段校验：要求必须能映射出 requiredDbFields
     */
    protected function assertRequiredFields(array $colToField): void
    {
        $fields = array_values($colToField);
        foreach ($this->requiredDbFields as $req) {
            if (!in_array($req, $fields, true)) {
                throw new BusinessException("Excel 表头缺少必要字段映射：{$req}（请补充映射或别名）");
            }
        }
    }

    /**
     * 表头标准化：
     * - 去 BOM
     * - trim
     * - ✅ 统一处理尾部多余的 ? / _（解决 xxx?_ 与 xxx?）
     *
     * 注意：为了避免误伤中文表头，这里默认不做 strtolower / 空格替换。
     * 若你后续想增强，可在注释处开启。
     */
    protected function normalizeHeader(string $header): string
    {
        // 去掉 UTF-8 BOM
        $header = preg_replace('/^\xEF\xBB\xBF/', '', $header);

        // 去掉前后空白
        $header = trim($header);

        if ($header === '') {
            return '';
        }

        // 可选增强（默认不开启，避免影响中文）：
        // $header = mb_strtolower($header);
        // $header = preg_replace('/\s+/', '_', $header);

        // ✅ 去掉末尾连续的 "_" / "?"
        $header = rtrim($header, "_?");

        return $header;
    }
}