<?php

namespace plugin\saiadmin\app\service;

/**
 * 读取既有代理、商户分成，不在设备运营中维护另一份比例。
 * 代理档案存占总交易额的比例；商户存相对直属代理的比例。
 */
class DeviceOperationShares
{
    private array $agents = [];
    private array $agentsByDepartment = [];

    public function __construct(array $agents)
    {
        foreach ($agents as $agent) {
            $rates = json_decode($agent['profit_rates'] ?? '{}', true);
            $agent['rates'] = is_array($rates) ? $rates : [];
            $this->agents[(int) $agent['id']] = $agent;
            $this->agentsByDepartment[(int) $agent['dept_id']][] = (int) $agent['id'];
        }
    }

    public function calculate(array $device, string $product): array
    {
        if (empty($device['merchant_id'])) {
            return ['merchant_rate' => 0.0, 'manager_rate' => 0.0];
        }
        $merchantAgent = (int) $device['merchant_agent_id'];
        $manager = (int) $device['manage_agent_id'];
        $parentRate = $this->agentRate($merchantAgent, $product);
        $relativeRate = $this->validRate($device['merchant_relative_rate']);

        // 不分成和入驻费没有按订单比例分成；明确的 0 不依赖上级档案。
        if (in_array($device['profit_method'], ['不分成', '入驻费'], true) || $relativeRate === 0.0) {
            $merchantRate = 0.0;
        } else {
            $merchantRate = $parentRate !== null && $relativeRate !== null
                ? round($parentRate * $relativeRate / 100, 4) : null;
        }

        $managerRate = $this->agentRate($manager, $product);
        if ($manager === $merchantAgent) {
            $childRate = $merchantRate;
        } else {
            $childId = $this->findBranchChild($manager, $merchantAgent);
            // 0 表示管理人不在这条分成链上；NULL 表示关系有歧义，不能猜测。
            if ($childId === 0) {
                return ['merchant_rate' => $merchantRate, 'manager_rate' => 0.0];
            }
            $childRate = $childId === null ? null : $this->agentRate($childId, $product);
        }
        $netManagerRate = $managerRate !== null && $childRate !== null && $managerRate >= $childRate
            ? round($managerRate - $childRate, 4) : null;
        return ['merchant_rate' => $merchantRate, 'manager_rate' => $netManagerRate];
    }

    private function agentRate(int $id, string $product): ?float
    {
        return $this->validRate($this->agents[$id]['rates'][$product] ?? null);
    }

    private function validRate(mixed $value): ?float
    {
        return is_numeric($value) && $value >= 0 && $value <= 100 ? (float) $value : null;
    }

    /** 沿商户代理的部门祖先路径，查找管理人下面参与该笔分成的第一个代理。 */
    private function findBranchChild(int $managerId, int $merchantAgentId): ?int
    {
        $manager = $this->agents[$managerId] ?? null;
        $merchantAgent = $this->agents[$merchantAgentId] ?? null;
        if (!$manager || !$merchantAgent) {
            return null;
        }
        $path = array_map('intval', array_filter(explode(',', $merchantAgent['dept_level'] ?? ''), 'strlen'));
        $path[] = (int) $merchantAgent['dept_id'];
        $position = array_search((int) $manager['dept_id'], $path, true);
        if ($position === false) {
            return 0;
        }
        if ((int) $manager['dept_id'] === (int) $merchantAgent['dept_id']) {
            return null;
        }
        foreach (array_slice($path, $position + 1) as $departmentId) {
            if ($departmentId === (int) $merchantAgent['dept_id']) {
                return $merchantAgentId;
            }
            $candidates = $this->agentsByDepartment[$departmentId] ?? [];
            if (count($candidates) > 1) {
                return null;
            }
            if (count($candidates) === 1) {
                return $candidates[0];
            }
        }
        return null;
    }
}