<?php

namespace App\Services;

use Illuminate\Support\Facades\DB;

/**
 * 项目规则校验服务
 */
class ItemRuleValidationService
{
    /**
     * 星期映射: 数字转中文
     */
    private const WEEKDAY_MAP = [
        1 => '周一',
        2 => '周二',
        3 => '周三',
        4 => '周四',
        5 => '周五',
        6 => '周六',
        7 => '周日',
    ];

    /**
     * 性别映射: 数据库值转中文
     */
    private const GENDER_MAP = [
        1 => '男',
        2 => '女',
        0 => '未知',
    ];

    /**
     * 校验项目规则
     *
     * @param array $itemCodes 检查项目code数组
     * @param int $patientId 患者ID
     * @param int $planId 号源ID
     * @return array ['valid' => bool, 'conflicts' => [...], 'patient_info' => [...], 'appointment_time' => '...']
     */
    public function validate(array $itemCodes, int $patientId, int $planId): array
    {
        // 1. 查询患者信息
        $patientInfo = $this->getPatientInfo($patientId);
        if (!$patientInfo) {
            return [
                'valid' => false,
                'conflicts' => [[
                    'type' => 'ITEM_RULE',
                    'rule_type' => '',
                    'item_code' => '',
                    'message' => '患者信息不存在',
                ]],
            ];
        }

        // 2. 查询预约时间
        $appointmentInfo = $this->getAppointmentInfo($planId);
        if (!$appointmentInfo) {
            return [
                'valid' => false,
                'conflicts' => [[
                    'type' => 'ITEM_RULE',
                    'rule_type' => '',
                    'item_code' => '',
                    'message' => '号源信息不存在',
                ]],
            ];
        }

        // 3. 查询项目及其绑定的规则
        $itemRules = $this->getItemRules($itemCodes);
        if (empty($itemRules)) {
            return [
                'valid' => true,
                'conflicts' => [],
                'patient_info' => $patientInfo,
                'appointment_time' => $appointmentInfo['full_time'],
            ];
        }

        // 4. 执行校验
        $conflicts = [];
        foreach ($itemRules as $itemCode => $rules) {
            foreach ($rules as $rule) {
                $conflict = $this->validateRule(
                    $rule,
                    $patientInfo,
                    $appointmentInfo,
                    $itemCode
                );
                if ($conflict) {
                    $conflicts[] = $conflict;
                }
            }
        }

        return [
            'valid' => empty($conflicts),
            'conflicts' => $conflicts,
            'patient_info' => $patientInfo,
            'appointment_time' => $appointmentInfo['full_time'],
        ];
    }

    /**
     * 获取患者信息
     */
    private function getPatientInfo(int $patientId): ?array
    {
        $application = DB::table('exam_application')
            ->where('patient_id', $patientId)
            ->orderBy('id', 'desc')
            ->select('patient_age', 'patient_gender')
            ->first();

        if (!$application) {
            return null;
        }

        return [
            'age' => $application->patient_age,
            'gender' => self::GENDER_MAP[$application->patient_gender] ?? '未知',
            'gender_raw' => $application->patient_gender,
        ];
    }

    /**
     * 获取预约信息
     */
    private function getAppointmentInfo(int $planId): ?array
    {
        $plan = DB::table('plan as p')
            ->join('plan_batch as pb', 'p.batch_id', '=', 'pb.id')
            ->where('p.id', $planId)
            ->select('pb.plan_date', 'p.start_time', 'p.end_time', 'pb.weekname')
            ->first();

        if (!$plan) {
            return null;
        }

        // 组合完整的预约时间
        $fullTime = $plan->plan_date . ' ' . $plan->start_time;

        return [
            'date' => $plan->plan_date,
            'start_time' => $plan->start_time,
            'end_time' => $plan->end_time,
            'weekday' => self::WEEKDAY_MAP[$plan->weekname] ?? '未知',
            'weekday_raw' => $plan->weekname,
            'full_time' => $fullTime,
        ];
    }

    /**
     * 获取项目绑定的规则
     */
    private function getItemRules(array $itemCodes): array
    {
        if (empty($itemCodes)) {
            return [];
        }

        // 获取项目ID
        $items = DB::table('exam_item')
            ->whereIn('code', $itemCodes)
            ->where('deleted', 0)
            ->select('id', 'code')
            ->get()
            ->keyBy('id')
            ->toArray();

        $itemIds = array_column($items, 'id');

        if (empty($itemIds)) {
            return [];
        }

        // 获取绑定的规则
        $rules = DB::table('exam_item_rule')
            ->whereIn('target_id', $itemIds)
            ->where('target_type', 'ITEM')
            ->where('status', 1)
            ->where('deleted', 0)
            ->select('target_id', 'rule_type', 'rule_value')
            ->get()
            ->toArray();

        // 按code分组
        $result = [];
        foreach ($rules as $rule) {
            $itemCode = $items[$rule->target_id]->code ?? null;
            if ($itemCode) {
                $rule->rule_value = json_decode($rule->rule_value, true);
                $result[$itemCode][] = $rule;
            }
        }

        return $result;
    }

    /**
     * 校验单个规则
     */
    private function validateRule(object $rule, array $patientInfo, array $appointmentInfo, string $itemCode): ?array
    {
        $ruleType = $rule->rule_type;
        $ruleValue = $rule->rule_value;

        switch ($ruleType) {
            case 'AGE_LIMIT':
                return $this->validateAgeLimit($ruleValue, $patientInfo, $itemCode);

            case 'GENDER_LIMIT':
                return $this->validateGenderLimit($ruleValue, $patientInfo, $itemCode);

            case 'TIME_RESTRICTION':
                return $this->validateTimeRestriction($ruleValue, $patientInfo, $appointmentInfo, $itemCode);

            default:
                return null;
        }
    }

    /**
     * 校验年龄限制
     */
    private function validateAgeLimit(array $ruleValue, array $patientInfo, string $itemCode): ?array
    {
        $minAge = (int)($ruleValue['min_age'] ?? 0);
        $maxAge = (int)($ruleValue['max_age'] ?? 150);
        $patientAge = (int)$patientInfo['age'];

        if ($patientAge < $minAge || $patientAge > $maxAge) {
            return [
                'type' => 'ITEM_RULE',
                'rule_type' => 'AGE_LIMIT',
                'item_code' => $itemCode,
                'message' => "年龄限制{$minAge}-{$maxAge}岁,患者年龄{$patientAge}岁不符合要求",
            ];
        }

        return null;
    }

    /**
     * 校验性别限制
     */
    private function validateGenderLimit(array $ruleValue, array $patientInfo, string $itemCode): ?array
    {
        $requiredGender = $ruleValue['gender'] ?? '';
        $patientGender = $patientInfo['gender'];

        if ($requiredGender && $patientGender !== $requiredGender && $patientGender !== '未知') {
            return [
                'type' => 'ITEM_RULE',
                'rule_type' => 'GENDER_LIMIT',
                'item_code' => $itemCode,
                'message' => "性别限制{$requiredGender},患者性别{$patientGender}不符合要求",
            ];
        }

        return null;
    }

    /**
     * 校验预约时间段限制
     */
    private function validateTimeRestriction(array $ruleValue, array $patientInfo, array $appointmentInfo, string $itemCode): ?array
    {
        $errors = [];

        // 校验时间段
        $startTime = $ruleValue['start_time'] ?? null;
        $endTime = $ruleValue['end_time'] ?? null;
        $appointmentStartTime = $appointmentInfo['start_time'];

        if ($startTime && $endTime) {
            // 比较时间,需要转换为时间戳
            $startTimestamp = strtotime('2000-01-01 ' . $startTime);
            $endTimestamp = strtotime('2000-01-01 ' . $endTime);
            $appointmentTimestamp = strtotime('2000-01-01 ' . $appointmentStartTime);

            if ($appointmentTimestamp < $startTimestamp || $appointmentTimestamp > $endTimestamp) {
                $errors[] = "预约时间{$appointmentStartTime}不在允许时间段({$startTime}-{$endTime})内";
            }
        }

        // 校验星期
        $allowedDays = $ruleValue['days'] ?? [];
        $appointmentWeekday = $appointmentInfo['weekday'];

        if (!empty($allowedDays) && !in_array($appointmentWeekday, $allowedDays)) {
            $daysStr = implode(',', $allowedDays);
            $errors[] = "预约日期为{$appointmentWeekday},仅允许在{$daysStr}预约";
        }

        if (!empty($errors)) {
            return [
                'type' => 'ITEM_RULE',
                'rule_type' => 'TIME_RESTRICTION',
                'item_code' => $itemCode,
                'message' => implode('; ', $errors),
            ];
        }

        return null;
    }
}