<?php

namespace App\Http\Controllers\Business;

use App\Models\Auth\User;
use App\Traits\Companies;
use Illuminate\Http\JsonResponse;
use Illuminate\Http\Request;
use Illuminate\Routing\Controller;
use Illuminate\Validation\ValidationException;
use Modules\EcommerceFinance\Services\AccountMappingCoa;
use Modules\EcommerceFinance\Services\AccountMappingStore;
use Modules\EcommerceFinance\Services\AccountMappingValidator;
use Modules\EcommerceFinance\Services\AccountMappingWorkbookImporter;
use Modules\EcommerceFinance\Services\AccountMappingResyncDispatcher;
use RuntimeException;
use Symfony\Component\HttpFoundation\StreamedResponse;

/**
 * 财务规则 · 科目映射表的维护接口。
 *
 * 表里存的是「科目对 + 方向基准」，不存最终借贷方向；方向在记账时按账单实际收支代入。
 * 本控制器只负责：增、改、删、导入追加、导出、模板、校验。
 */
class AccountMappingActions extends Controller
{
    use Companies;

    /** 操作记录保留并展示的条数 */
    private const HISTORY_LIMIT = 500;

    private const HISTORY_ACTION_LABELS = [
        'create' => '新增',
        'update' => '修改',
        'delete' => '删除',
        'import' => '导入',
        'reset' => '重置',
    ];

    private const HISTORY_FIELD_LABELS = [
        'platform' => '平台',
        'item' => '账单项目',
        'memo' => '财务备注',
        'invoice' => '票据口径',
        'category' => '大类',
        'dAcct' => '借方科目',
        'dSub' => '借方二级',
        'cAcct' => '贷方科目',
        'cSub' => '贷方二级',
        'basis' => '方向基准',
    ];

    public function __construct(
        private readonly AccountMappingStore $store,
        private readonly AccountMappingValidator $validator,
        private readonly AccountMappingCoa $coa,
        private readonly AccountMappingWorkbookImporter $importer,
    ) {
        $this->middleware('auth');
        $this->middleware('company.identify');
    }

    /** 全量规则 + 校验结果 + 筛选项 */
    public function index(): JsonResponse
    {
        return response()->json($this->payload());
    }

    public function store(Request $request): JsonResponse
    {
        $values = $this->payloadValues($request);
        if (trim((string) ($values['platform'] ?? '')) === '' || trim((string) ($values['item'] ?? '')) === '') {
            throw ValidationException::withMessages(['platform' => '平台和账单项目不能为空。']);
        }

        $this->store->create($values, $this->userId());

        $hint = $this->dispatchResync([(string) ($values['platform'] ?? '')]);

        return response()->json(['message' => '已新增 1 条规则。' . $hint] + $this->payload());
    }

    public function update(Request $request, int $id): JsonResponse
    {
        $before = $this->store->find($id);
        if ($before === null) {
            throw ValidationException::withMessages(['id' => '这条规则已经不存在了，请刷新页面。']);
        }

        $values = $this->payloadValues($request);
        $this->store->update($id, $values, $this->userId());

        $hint = $this->dispatchResync([(string) ($before['platform'] ?? ''), (string) ($values['platform'] ?? '')]);

        return response()->json(['message' => '已保存。' . $hint] + $this->payload());
    }

    public function destroy(int $id): JsonResponse
    {
        $before = $this->store->find($id);
        if (! $this->store->destroy($id, $this->userId())) {
            throw ValidationException::withMessages(['id' => '这条规则已经不存在了，请刷新页面。']);
        }

        $hint = $this->dispatchResync([(string) ($before['platform'] ?? '')]);

        return response()->json(['message' => '已删除 1 条规则。' . $hint] + $this->payload());
    }

    /**
     * 操作记录：最近 500 条（新增 / 修改 / 删除 / 导入 / 重置）。
     *
     * 每条含改动前、改动后的完整规则内容，所以能查出「谁在什么时候把哪个字段从什么改成了什么」，
     * 也能据此还原被删掉的行。操作人只返回名称，不返回账号等敏感字段。
     */
    public function history(): JsonResponse
    {
        $events = $this->historyEvents();

        return response()->json([
            'events' => $events,
            'total' => count($events),
            'limit' => self::HISTORY_LIMIT,
        ]);
    }

    /**
     * 操作记录导出为 CSV，筛选口径与页面上的「操作记录」一致。
     */
    public function historyExport(Request $request): StreamedResponse
    {
        $action = trim((string) $request->query('action', ''));
        $keyword = trim((string) $request->query('keyword', ''));

        $rows = array_values(array_filter(
            $this->historyEvents(),
            fn (array $row): bool => $this->historyMatches($row, $action, $keyword)
        ));

        return response()->streamDownload(function () use ($rows): void {
            $handle = fopen('php://output', 'w');
            fwrite($handle, "\xEF\xBB\xBF");
            fputcsv($handle, ['时间', '操作', '平台', '账单项目', '财务备注', '变更内容', '操作人']);
            foreach ($rows as $row) {
                fputcsv($handle, [
                    $row['at'], $row['action_label'], $row['platform'], $row['item'], $row['memo'],
                    implode('；', $row['changes']), $row['actor'],
                ]);
            }
            fclose($handle);
        }, '科目映射表_操作记录.csv', [
            'Content-Type' => 'text/csv; charset=UTF-8',
            'Cache-Control' => 'private, no-store',
        ]);
    }

    /**
     * 按操作记录恢复：被删除的规则重新建回来，被改过的规则恢复成改前内容。
     *
     * 前端传的是「记录在列表里的位置 + 时间 + 操作 + 规则号」，三者都对得上才动手，
     * 避免这期间有人新增了记录、位置发生偏移时恢复错行。
     */
    public function historyRestore(Request $request): JsonResponse
    {
        $index = (int) $request->input('index', -1);
        $at = trim((string) $request->input('at', ''));
        $action = trim((string) $request->input('action', ''));
        $ruleId = (int) $request->input('id', 0);

        $event = $this->store->events(self::HISTORY_LIMIT)[$index] ?? null;

        if ($event === null
            || (string) ($event['at'] ?? '') !== $at
            || (string) ($event['action'] ?? '') !== $action
            || (int) ($event['id'] ?? 0) !== $ruleId) {
            throw ValidationException::withMessages(['history' => '操作记录已经变化，请关掉面板重新打开再试。']);
        }

        $before = is_array($event['before'] ?? null) ? $event['before'] : null;
        if ($before === null) {
            throw ValidationException::withMessages(['history' => '这条记录没有可恢复的内容。']);
        }

        if ($action === 'delete') {
            foreach ($this->store->all() as $rule) {
                if ($this->store->keyOf($rule) === $this->store->keyOf($before)) {
                    throw ValidationException::withMessages([
                        'history' => '这条规则已经在表里了（记录 #' . (int) $rule['id'] . '），不用恢复。',
                    ]);
                }
            }

            $restored = $this->store->create($before, $this->userId());
            $hint = $this->dispatchResync([(string) ($restored['platform'] ?? '')]);

            return response()->json([
                'message' => '已恢复「' . $restored['platform'] . ' · ' . $restored['item'] . '」（新记录 #' . (int) $restored['id'] . '）。' . $hint,
            ] + $this->payload());
        }

        if ($action === 'update') {
            $current = $this->store->find($ruleId);
            if ($current === null) {
                throw ValidationException::withMessages(['history' => '这条规则已经被删掉了，请用同一条的「删除」记录恢复。']);
            }

            $this->store->update($ruleId, $before, $this->userId());
            $hint = $this->dispatchResync([(string) ($current['platform'] ?? ''), (string) ($before['platform'] ?? '')]);

            return response()->json([
                'message' => '已恢复成这次修改前的内容（记录 #' . $ruleId . '）。' . $hint,
            ] + $this->payload());
        }

        throw ValidationException::withMessages(['history' => '只有「删除」和「修改」的记录可以恢复。']);
    }

    /**
     * 导入预览：只解析、不落盘。
     *
     * 单独一条路由、且不挂 throttle:import —— 因为平台对「导入」限的是 1 次/分钟，
     * 而页面上「预览 → 确认导入」天然要发两次请求，预览走限流必然 429。
     */
    public function preview(Request $request): JsonResponse
    {
        return response()->json($this->previewPayload($this->workbookFile($request)));
    }

    /**
     * 导入落盘。带 ?dry_run=1 时行为同 preview（保留兼容）。
     */
    public function import(Request $request): JsonResponse
    {
        $file = $this->workbookFile($request);

        if ($request->boolean('dry_run')) {
            return response()->json($this->previewPayload($file));
        }

        $parsed = $this->importer->parse($file);
        $result = $this->store->importRows($parsed['rows'], $request->boolean('overwrite'), $this->userId());
        $message = "导入完成：识别 {$result['total']} 行，新增 {$result['created']} 条，更新 {$result['updated']} 条，跳过重复 {$result['skipped']} 条。";
        $platforms = array_values(array_unique(array_map(
            static fn (array $row): string => (string) ($row['platform'] ?? ''),
            $parsed['rows']
        )));
        $message .= $this->dispatchResync($platforms);

        return response()->json(['message' => $message, 'result' => $result] + $this->payload());
    }

    /**
     * 取上传的工作簿。
     *
     * 这里**故意不用** `mimes:xlsx,xls,csv`：那个规则靠 libmagic 嗅探真实类型，
     * 而只有两三行的 CSV 会被猜成 `text/plain`、扩展名算成 `txt`，于是合法文件被拒
     * （实测 2 行 231B 的 csv 报「必须是 xlsx, xls, csv 的文件」）。按扩展名判就稳。
     */
    protected function workbookFile(Request $request)
    {
        $request->validate([
            'import' => ['required', 'file', 'max:10240'],
        ], [
            'import.required' => '请先选择要导入的文件。',
            'import.file' => '请选择要导入的文件。',
            'import.max' => '文件不能超过 10MB。',
        ]);

        $file = $request->file('import');
        $extension = mb_strtolower((string) $file->getClientOriginalExtension());

        if (! in_array($extension, ['xlsx', 'xls', 'csv'], true)) {
            throw ValidationException::withMessages([
                'import' => '只支持 xlsx、xls、csv 三种格式，当前是「' . $extension . '」。',
            ]);
        }

        return $file;
    }

    /**
     * @param \Illuminate\Http\UploadedFile $file
     * @return array<string,mixed>
     */
    protected function previewPayload($file): array
    {
        $parsed = $this->importer->parse($file);
        $rows = $parsed['rows'];

        $existing = [];
        foreach ($this->store->all() as $rule) {
            $existing[$this->store->keyOf($rule)] = true;
        }

        $fresh = [];
        $duplicated = [];
        foreach ($rows as $row) {
            $key = $this->store->keyOf($row);
            if (isset($existing[$key])) {
                $duplicated[$key] = ($duplicated[$key] ?? 0) + 1;
            } else {
                $fresh[$key] = true;
                $existing[$key] = true;
            }
        }

        return [
            'dry_run' => true,
            'sheet' => $parsed['sheet'],
            'total' => count($rows),
            'can_create' => count($fresh),
            'can_overwrite' => count($duplicated),
            'duplicate_keys' => array_slice(array_keys($duplicated), 0, 20),
            'sample' => array_slice($rows, 0, 6),
        ];
    }

    /** 恢复成初始 112 条 */
    public function reset(): JsonResponse
    {
        $total = $this->store->reset($this->userId());

        return response()->json(['message' => "已恢复为初始 {$total} 条规则。" . $this->dispatchResyncAll()] + $this->payload());
    }

    /** 账套科目（一级 + 各一级下的明细），供下拉使用 */
    public function accounts(): JsonResponse
    {
        $level1 = $this->coa->level1();
        $children = [];
        foreach ($level1 as $account) {
            $children[$account['code']] = $this->coa->descendants($account['code']);
        }

        return response()->json(['level1' => $level1, 'children' => $children]);
    }

    /** 按当前表导出 CSV（Excel 可直接打开） */
    public function export(): StreamedResponse
    {
        $rules = $this->store->all();

        return response()->streamDownload(function () use ($rules): void {
            $csv = fopen('php://output', 'w');
            if ($csv === false) {
                throw new RuntimeException('无法创建导出文件。');
            }
            fputs($csv, chr(0xEF) . chr(0xBB) . chr(0xBF));
            fputcsv($csv, array_values(AccountMappingStore::LABELS));

            foreach ($rules as $rule) {
                $row = [];
                foreach (array_keys(AccountMappingStore::LABELS) as $field) {
                    $value = (string) ($rule[$field] ?? '');
                    // 商品名称关键词留空时导出成「-」，与页面一致（导回来会按空处理）
                    if ($field === 'goods' && trim($value) === '') {
                        $value = '-';
                    }
                    $row[] = $this->csvText($value);
                }
                fputcsv($csv, $row);
            }
            fclose($csv);
        }, '科目映射表_' . $this->store->platformNow()->format('Ymd_His') . '.csv', [
            'Content-Type' => 'text/csv; charset=UTF-8',
            'Cache-Control' => 'private, no-store',
        ]);
    }

    /** 导入模板（表头 + 两条示例，并且这一份可以直接改完再导回来） */
    public function template(): StreamedResponse
    {
        $samples = [
            ['得物', '平台服务费', '平台服务费', '0.06', '费用', '销售费用', '平台佣金', '其他货币资金', '', '支出基准'],
            ['淘宝', '交易收入', '订单', '-', '收入', '其他货币资金', '', '主营业务收入', '', '收入基准'],
        ];

        return response()->streamDownload(function () use ($samples): void {
            $csv = fopen('php://output', 'w');
            if ($csv === false) {
                throw new RuntimeException('无法创建模板文件。');
            }
            fputs($csv, chr(0xEF) . chr(0xBB) . chr(0xBF));
            fputcsv($csv, array_values(AccountMappingStore::LABELS));
            foreach ($samples as $sample) {
                fputcsv($csv, $sample);
            }
            fclose($csv);
        }, '科目映射表_导入模板.csv', [
            'Content-Type' => 'text/csv; charset=UTF-8',
            'Cache-Control' => 'private, no-store',
        ]);
    }

    /** @return array<string,mixed> */
    private function payload(): array
    {
        $rules = $this->store->all();
        $validated = $this->validator->validate($rules);

        $rows = [];
        foreach ($rules as $rule) {
            $rows[] = $rule + ['issues' => $validated['issues'][(int) $rule['id']] ?? []];
        }

        return [
            'rules' => $rows,
            'summary' => $validated['summary'],
            'options' => $this->store->options(),
            'events' => $this->store->events(20),
        ];
    }

    /** @return array<string,string> */
    private function payloadValues(Request $request): array
    {
        $input = (array) $request->input('values', $request->all());

        return $this->store->normalize($input);
    }

    private function userId(): ?int
    {
        return user_id() ? (int) user_id() : null;
    }

    /**
     * 保存映射后把受影响的平台排进后台重跑队列。
     *
     * 映射表本身是实时读取的，但业绩明细的优惠/冲减/退款金额是同步时落库的，
     * 所以保存成功后需要自动重跑对应平台和月份。队列创建失败不能把已经保存成功的规则回滚。
     *
     * @param list<string> $platforms
     */
    private function dispatchResync(array $platforms): string
    {
        try {
            $result = app(AccountMappingResyncDispatcher::class)->dispatchFor($platforms);
        } catch (\Throwable $exception) {
            report($exception);

            return ' 业绩明细自动重跑任务创建失败，请稍后重试保存或联系管理员。';
        }

        return $result['jobs'] > 0
            ? " 业绩明细已自动排队重跑：{$result['jobs']} 个平台×月份任务，后台依次执行。"
            : '';
    }

    private function dispatchResyncAll(): string
    {
        try {
            $result = app(AccountMappingResyncDispatcher::class)->dispatchAll();
        } catch (\Throwable $exception) {
            report($exception);

            return ' 业绩明细自动重跑任务创建失败，请稍后重试或联系管理员。';
        }

        return $result['jobs'] > 0
            ? " 业绩明细已自动排队重跑：{$result['jobs']} 个平台×月份任务，后台依次执行。"
            : '';
    }

    /**
     * 原始操作记录 + 页面/CSV 直接可用的字段（变更内容与操作人只在服务端算一次）。
     *
     * @return array<int,array<string,mixed>>
     */
    private function historyEvents(): array
    {
        $events = $this->store->events(self::HISTORY_LIMIT);
        $names = $this->historyUserNames($events);

        $rows = [];
        foreach ($events as $event) {
            $before = is_array($event['before'] ?? null) ? $event['before'] : null;
            $after = is_array($event['after'] ?? null) ? $event['after'] : null;
            $rule = $before ?? $after ?? [];
            $action = (string) ($event['action'] ?? '');

            $rows[] = $event + [
                'action_label' => self::HISTORY_ACTION_LABELS[$action] ?? $action,
                'platform' => trim((string) ($rule['platform'] ?? '')),
                'item' => trim((string) ($rule['item'] ?? '')),
                'memo' => trim((string) ($rule['memo'] ?? '')),
                'changes' => $this->historyChangeParts($event, $before, $after),
                'actor' => $this->historyActor($event, $names),
            ];
        }

        return $rows;
    }

    /**
     * @param array<int,array<string,mixed>> $events
     * @return array<int,string>
     */
    private function historyUserNames(array $events): array
    {
        $ids = [];
        foreach ($events as $event) {
            $userId = (int) ($event['user_id'] ?? 0);
            if ($userId > 0) {
                $ids[$userId] = true;
            }
        }

        if ($ids === []) {
            return [];
        }

        return User::query()->whereIn('id', array_keys($ids))->pluck('name', 'id')->all();
    }

    /**
     * @param array<string,mixed> $event
     * @param array<int,string> $names
     */
    private function historyActor(array $event, array $names): string
    {
        $userId = (int) ($event['user_id'] ?? 0);

        if ($userId <= 0) {
            return '脚本 / 系统';
        }

        return $names[$userId] ?? ('用户 #' . $userId);
    }

    /**
     * 变更内容：修改给出「字段：改前 → 改后」，删除/新增给出科目对摘要，导入/重置给出条数。
     *
     * @param array<string,mixed> $event
     * @param array<string,string>|null $before
     * @param array<string,string>|null $after
     * @return array<int,string>
     */
    private function historyChangeParts(array $event, ?array $before, ?array $after): array
    {
        $action = (string) ($event['action'] ?? '');

        if ($action === 'update') {
            $parts = [];
            foreach (self::HISTORY_FIELD_LABELS as $field => $label) {
                $old = trim((string) ($before[$field] ?? ''));
                $new = trim((string) ($after[$field] ?? ''));
                if ($old === $new) {
                    continue;
                }
                $parts[] = $label . '：' . ($old === '' ? '（空）' : $old) . ' → ' . ($new === '' ? '（空）' : $new);
            }

            return $parts === [] ? ['未识别到字段变化'] : $parts;
        }

        if ($action === 'delete') {
            return ['删除前：' . $this->historyRuleSummary($before)];
        }

        if ($action === 'create') {
            return ['新增：' . $this->historyRuleSummary($after)];
        }

        if ($action === 'import') {
            $parts = [];
            foreach (['created' => '新增', 'updated' => '更新', 'skipped' => '跳过'] as $key => $label) {
                if (isset($event[$key])) {
                    $parts[] = $label . ' ' . (int) $event[$key];
                }
            }

            return ['导入：' . ($parts === [] ? '—' : implode(' · ', $parts))];
        }

        if ($action === 'reset') {
            return ['重置为初始规则' . (isset($event['total']) ? '（' . (int) $event['total'] . ' 条）' : '')];
        }

        return [$this->historyRuleSummary($before ?? $after)];
    }

    /** @param array<string,string>|null $rule */
    private function historyRuleSummary(?array $rule): string
    {
        $rule ??= [];
        $side = static function (string $acctKey, string $subKey) use ($rule): string {
            $acct = trim((string) ($rule[$acctKey] ?? ''));
            $sub = trim((string) ($rule[$subKey] ?? ''));
            if ($acct === '' && $sub === '') {
                return '—';
            }
            if ($sub === '' || $sub === $acct) {
                return $acct !== '' ? $acct : $sub;
            }

            return $acct . ' / ' . $sub;
        };

        return '借 ' . $side('dAcct', 'dSub') . ' ｜ 贷 ' . $side('cAcct', 'cSub')
            . ' ｜ ' . (trim((string) ($rule['category'] ?? '')) ?: '—')
            . ' · ' . (trim((string) ($rule['basis'] ?? '')) ?: '—')
            . ' · 票据 ' . (trim((string) ($rule['invoice'] ?? '')) ?: '—');
    }

    /** @param array<string,mixed> $row */
    private function historyMatches(array $row, string $action, string $keyword): bool
    {
        if ($action !== '' && (string) ($row['action'] ?? '') !== $action) {
            return false;
        }

        if ($keyword === '') {
            return true;
        }

        $haystack = mb_strtolower(implode(' ', [
            $row['platform'] ?? '',
            $row['item'] ?? '',
            $row['memo'] ?? '',
            $row['actor'] ?? '',
            implode(' ', (array) ($row['changes'] ?? [])),
        ]));

        return str_contains($haystack, mb_strtolower($keyword));
    }

    private function csvText(mixed $value): string
    {
        $value = (string) $value;

        return preg_match('/^[=+\-@\t\r]/u', $value) === 1 ? "\t" . $value : $value;
    }
}