<?php

namespace App\Models;

use Illuminate\Database\Eloquent\Model;
use Illuminate\Database\Eloquent\Factories\HasFactory;
use Illuminate\Database\Eloquent\Relations\HasMany;
use InvalidArgumentException;
use Carbon\Carbon;

class Plan extends Model
{
    use HasFactory;

    protected $table = 'v2_plan';
    protected $dateFormat = 'U';

    // 定义流量重置方式
    public const RESET_TRAFFIC_FOLLOW_SYSTEM = 0;    // 跟随系统设置
    public const RESET_TRAFFIC_FIRST_DAY_MONTH = 1;  // 每月1号
    public const RESET_TRAFFIC_MONTHLY = 2;          // 按月重置
    public const RESET_TRAFFIC_NEVER = 3;            // 不重置
    public const RESET_TRAFFIC_FIRST_DAY_YEAR = 4;   // 每年1月1日
    public const RESET_TRAFFIC_YEARLY = 5;           // 按年重置

    // 定义价格类型
    public const PRICE_TYPE_RESET_TRAFFIC = 'reset_traffic';  // 重置流量价格

    // 定义可用的订阅周期
    public const PERIOD_MONTHLY = 'monthly';
    public const PERIOD_QUARTERLY = 'quarterly';
    public const PERIOD_HALF_YEARLY = 'half_yearly';
    public const PERIOD_YEARLY = 'yearly';
    public const PERIOD_TWO_YEARLY = 'two_yearly';
    public const PERIOD_THREE_YEARLY = 'three_yearly';
    public const PERIOD_ONETIME = 'onetime';
    public const PERIOD_RESET_TRAFFIC = 'reset_traffic';

    // 定义旧版周期映射
    public const LEGACY_PERIOD_MAPPING = [
        'month_price' => self::PERIOD_MONTHLY,
        'quarter_price' => self::PERIOD_QUARTERLY,
        'half_year_price' => self::PERIOD_HALF_YEARLY,
        'year_price' => self::PERIOD_YEARLY,
        'two_year_price' => self::PERIOD_TWO_YEARLY,
        'three_year_price' => self::PERIOD_THREE_YEARLY,
        'onetime_price' => self::PERIOD_ONETIME,
        'reset_price' => self::PERIOD_RESET_TRAFFIC
    ];

    protected $fillable = [
        'group_id',
        'transfer_enable',
        'name',
        'speed_limit',
        'show',
        'sort',
        'renew',
        'content',
        'prices',
        'reset_traffic_method',
        'capacity_limit',
        'sell'
    ];

    protected $casts = [
        'show' => 'boolean',
        'renew' => 'boolean',
        'created_at' => 'timestamp',
        'updated_at' => 'timestamp',
        'group_id' => 'integer',
        'prices' => 'array',
        'reset_traffic_method' => 'integer',
    ];

    /**
     * 获取所有可用的流量重置方式
     *
     * @return array
     */
    public static function getResetTrafficMethods(): array
    {
        return [
            self::RESET_TRAFFIC_FOLLOW_SYSTEM => '跟随系统设置',
            self::RESET_TRAFFIC_FIRST_DAY_MONTH => '每月1号',
            self::RESET_TRAFFIC_MONTHLY => '按月重置',
            self::RESET_TRAFFIC_NEVER => '不重置',
            self::RESET_TRAFFIC_FIRST_DAY_YEAR => '每年1月1日',
            self::RESET_TRAFFIC_YEARLY => '按年重置',
        ];
    }

    /**
     * 获取下一次流量重置时间
     *
     * @param Carbon|null $from 计算起始时间，默认为当前时间
     * @return Carbon|null 下次重置时间，如果不重置则返回null
     */
    public function getNextResetTime(?Carbon $from = null): ?Carbon
    {
        $from = $from ?? Carbon::now();

        switch ($this->reset_traffic_method) {
            case self::RESET_TRAFFIC_FIRST_DAY_MONTH:
                return $from->copy()->addMonth()->startOfMonth();

            case self::RESET_TRAFFIC_MONTHLY:
                return $from->copy()->addMonth()->startOfDay();

            case self::RESET_TRAFFIC_FIRST_DAY_YEAR:
                return $from->copy()->addYear()->startOfYear();

            case self::RESET_TRAFFIC_YEARLY:
                return $from->copy()->addYear()->startOfDay();

            case self::RESET_TRAFFIC_NEVER:
                return null;

            case self::RESET_TRAFFIC_FOLLOW_SYSTEM:
            default:
                // 这里需要实现获取系统设置的逻辑
                // 可以通过系统配置或其他方式获取
                return null;
        }
    }

    /**
     * 检查是否需要重置流量
     *
     * @param Carbon|null $checkTime 检查时间点，默认为当前时间
     * @return bool
     */
    public function shouldResetTraffic(?Carbon $checkTime = null): bool
    {
        if ($this->reset_traffic_method === self::RESET_TRAFFIC_NEVER) {
            return false;
        }

        $checkTime = $checkTime ?? Carbon::now();
        $nextResetTime = $this->getNextResetTime($checkTime);

        if ($nextResetTime === null) {
            return false;
        }

        return $checkTime->greaterThanOrEqualTo($nextResetTime);
    }

    /**
     * 获取流量重置方式的描述
     *
     * @return string
     */
    public function getResetTrafficMethodName(): string
    {
        return self::getResetTrafficMethods()[$this->reset_traffic_method] ?? '未知';
    }

    /**
     * 获取所有可用的订阅周期
     *
     * @return array
     */
    public static function getAvailablePeriods(): array
    {
        return [
            self::PERIOD_MONTHLY => [
                'name' => '月付',
                'days' => 30,
                'value' => 1
            ],
            self::PERIOD_QUARTERLY => [
                'name' => '季付',
                'days' => 90,
                'value' => 3
            ],
            self::PERIOD_HALF_YEARLY => [
                'name' => '半年付',
                'days' => 180,
                'value' => 6
            ],
            self::PERIOD_YEARLY => [
                'name' => '年付',
                'days' => 365,
                'value' => 12
            ],
            self::PERIOD_TWO_YEARLY => [
                'name' => '两年付',
                'days' => 730,
                'value' => 24
            ],
            self::PERIOD_THREE_YEARLY => [
                'name' => '三年付',
                'days' => 1095,
                'value' => 36
            ],
            self::PERIOD_ONETIME => [
                'name' => '一次性',
                'days' => -1,
                'value' => -1
            ],
            self::PERIOD_RESET_TRAFFIC => [
                'name' => '重置流量',
                'days' => -1,
                'value' => -1
            ],
        ];
    }

    /**
     * 获取指定周期的价格
     *
     * @param string $period
     * @return int|null
     */
    public function getPriceByPeriod(string $period): ?int
    {
        return $this->prices[$period] ?? null;
    }

    /**
     * 获取所有已设置价格的周期
     *
     * @return array
     */
    public function getActivePeriods(): array
    {
        return array_filter(
            self::getAvailablePeriods(),
            fn($period) => isset($this->prices[$period])
            && $this->prices[$period] > 0,
            ARRAY_FILTER_USE_KEY
        );
    }

    /**
     * 设置指定周期的价格
     *
     * @param string $period
     * @param int $price
     * @return void
     * @throws InvalidArgumentException
     */
    public function setPeriodPrice(string $period, int $price): void
    {
        if (!array_key_exists($period, self::getAvailablePeriods())) {
            throw new InvalidArgumentException("Invalid period: {$period}");
        }

        $prices = $this->prices ?? [];
        $prices[$period] = $price;
        $this->prices = $prices;
    }

    /**
     * 移除指定周期的价格
     *
     * @param string $period
     * @return void
     */
    public function removePeriodPrice(string $period): void
    {
        $prices = $this->prices ?? [];
        unset($prices[$period]);
        $this->prices = $prices;
    }

    /**
     * 获取所有价格及其对应的周期信息
     *
     * @return array
     */
    public function getPriceList(): array
    {
        $prices = $this->prices ?? [];
        $periods = self::getAvailablePeriods();

        $priceList = [];
        foreach ($prices as $period => $price) {
            if (isset($periods[$period]) && $price > 0) {
                $priceList[$period] = [
                    'period' => $periods[$period],
                    'price' => $price,
                    'average_price' => $periods[$period]['value'] > 0
                        ? round($price / $periods[$period]['value'], 2)
                        : $price
                ];
            }
        }

        return $priceList;
    }

    /**
     * 检查是否可以重置流量
     *
     * @return bool
     */
    public function canResetTraffic(): bool
    {
        return $this->reset_traffic_method !== self::RESET_TRAFFIC_NEVER
            && $this->getResetTrafficPrice() > 0;
    }

    /**
     * 获取重置流量的价格
     *
     * @return int
     */
    public function getResetTrafficPrice(): int
    {
        return $this->prices[self::PRICE_TYPE_RESET_TRAFFIC] ?? 0;
    }

    /**
     * 计算指定周期的有效天数
     *
     * @param string $period
     * @return int -1表示永久有效
     * @throws InvalidArgumentException
     */
    public static function getPeriodDays(string $period): int
    {
        $periods = self::getAvailablePeriods();
        if (!isset($periods[$period])) {
            throw new InvalidArgumentException("Invalid period: {$period}");
        }

        return $periods[$period]['days'];
    }

    /**
     * 检查周期是否有效
     *
     * @param string $period
     * @return bool
     */
    public static function isValidPeriod(string $period): bool
    {
        return array_key_exists($period, self::getAvailablePeriods());
    }

    public function users(): HasMany
    {
        return $this->hasMany(User::class);
    }

    public function group()
    {
        return $this->hasOne(ServerGroup::class, 'id', 'group_id');
    }

    public function orders(): HasMany
    {
        return $this->hasMany(Order::class);
    }

    /**
     * 设置流量重置方式
     *
     * @param int $method
     * @return void
     * @throws InvalidArgumentException
     */
    public function setResetTrafficMethod(int $method): void
    {
        if (!array_key_exists($method, self::getResetTrafficMethods())) {
            throw new InvalidArgumentException("Invalid reset traffic method: {$method}");
        }

        $this->reset_traffic_method = $method;
    }

    /**
     * 设置重置流量价格
     *
     * @param int $price
     * @return void
     */
    public function setResetTrafficPrice(int $price): void
    {
        $prices = $this->prices ?? [];
        $prices[self::PRICE_TYPE_RESET_TRAFFIC] = max(0, $price);
        $this->prices = $prices;
    }
}