<?php

namespace App\Services;

use App\Models\SopTemplate;
use App\Models\SopTemplateVersion;
use Illuminate\Support\Facades\DB;
use Illuminate\Support\Facades\Validator;
use Illuminate\Validation\ValidationException;

class SopTemplateService
{
    /**
     * 导出模板为 JSON 格式
     *
     * @param SopTemplate $template
     * @return string
     */
    public function exportToJson(SopTemplate $template): string
    {
        $data = [
            'template' => [
                'name' => $template->name,
                'description' => $template->description,
                'category' => $template->category,
                'tags' => $template->tags,
                'version' => $template->version,
                'applicable_departments' => $template->applicable_departments,
                'applicable_positions' => $template->applicable_positions,
            ],
            'steps' => $template->steps->map(function ($step) {
                return [
                    'step_number' => $step->step_number,
                    'title' => $step->title,
                    'content' => $step->content,
                    'sort_order' => $step->sort_order,
                    'is_required' => $step->is_required,
                    'interactive_tasks' => $step->interactiveTasks->map(function ($task) {
                        return [
                            'task_type' => $task->task_type,
                            'task_config' => $task->task_config,
                            'validation_rules' => $task->validation_rules,
                            'timeout_seconds' => $task->timeout_seconds,
                            'is_required' => $task->is_required,
                        ];
                    })->toArray(),
                ];
            })->toArray(),
            'exported_at' => now()->toIso8601String(),
            'exported_by' => auth()->user()?->name,
        ];

        return json_encode($data, JSON_PRETTY_PRINT | JSON_UNESCAPED_UNICODE);
    }

    /**
     * 从 JSON 导入模板
     *
     * @param string $json
     * @return SopTemplate
     * @throws ValidationException
     */
    public function importFromJson(string $json): SopTemplate
    {
        $data = json_decode($json, true);

        if (json_last_error() !== JSON_ERROR_NONE) {
            throw ValidationException::withMessages([
                'file' => ['无效的 JSON 格式'],
            ]);
        }

        // 验证数据结构
        $validator = Validator::make($data, [
            'template' => 'required|array',
            'template.name' => 'required|string|max:255',
            'template.version' => 'required|string|max:50',
            'steps' => 'required|array|min:1',
            'steps.*.step_number' => 'required|integer',
            'steps.*.title' => 'required|string|max:255',
        ]);

        if ($validator->fails()) {
            throw new ValidationException($validator);
        }

        return DB::transaction(function () use ($data) {
            // 创建模板
            $template = SopTemplate::create([
                'name' => $data['template']['name'],
                'description' => $data['template']['description'] ?? null,
                'category' => $data['template']['category'] ?? null,
                'tags' => $data['template']['tags'] ?? [],
                'version' => $data['template']['version'],
                'status' => 'draft',
                'applicable_departments' => $data['template']['applicable_departments'] ?? [],
                'applicable_positions' => $data['template']['applicable_positions'] ?? [],
                'created_by' => auth()->id(),
            ]);

            // 创建步骤
            foreach ($data['steps'] as $stepData) {
                $step = $template->steps()->create([
                    'step_number' => $stepData['step_number'],
                    'title' => $stepData['title'],
                    'content' => $stepData['content'] ?? null,
                    'sort_order' => $stepData['sort_order'] ?? $stepData['step_number'],
                    'is_required' => $stepData['is_required'] ?? true,
                ]);

                // 创建交互任务
                if (!empty($stepData['interactive_tasks'])) {
                    foreach ($stepData['interactive_tasks'] as $taskData) {
                        $step->interactiveTasks()->create([
                            'task_type' => $taskData['task_type'],
                            'task_config' => $taskData['task_config'] ?? [],
                            'validation_rules' => $taskData['validation_rules'] ?? [],
                            'timeout_seconds' => $taskData['timeout_seconds'] ?? null,
                            'is_required' => $taskData['is_required'] ?? true,
                        ]);
                    }
                }
            }

            return $template;
        });
    }

    /**
     * 发布模板
     *
     * @param SopTemplate $template
     * @param string|null $changeLog
     * @return void
     */
    public function publish(SopTemplate $template, ?string $changeLog = null): void
    {
        // 创建版本快照
        $this->createVersion($template, $changeLog);

        // 更新状态
        $template->update([
            'status' => 'published',
            'published_at' => now(),
        ]);
    }

    /**
     * 创建版本快照
     *
     * @param SopTemplate $template
     * @param string|null $changeLog
     * @return SopTemplateVersion
     */
    public function createVersion(SopTemplate $template, ?string $changeLog = null): SopTemplateVersion
    {
        return SopTemplateVersion::create([
            'sop_template_id' => $template->id,
            'version' => $template->version,
            'change_log' => $changeLog ?? '版本快照',
            'content_snapshot' => [
                'template' => $template->toArray(),
                'steps' => $template->steps->map(function ($step) {
                    return array_merge($step->toArray(), [
                        'interactive_tasks' => $step->interactiveTasks->toArray(),
                    ]);
                })->toArray(),
            ],
            'created_by' => auth()->id(),
            'created_at' => now(),
        ]);
    }

    /**
     * 归档模板
     *
     * @param SopTemplate $template
     * @return void
     */
    public function archive(SopTemplate $template): void
    {
        $template->update([
            'status' => 'archived',
        ]);
    }

    /**
     * 复制模板
     *
     * @param SopTemplate $template
     * @param string $newName
     * @return SopTemplate
     */
    public function duplicate(SopTemplate $template, string $newName): SopTemplate
    {
        return DB::transaction(function () use ($template, $newName) {
            // 复制模板
            $newTemplate = $template->replicate();
            $newTemplate->name = $newName;
            $newTemplate->status = 'draft';
            $newTemplate->published_at = null;
            $newTemplate->created_by = auth()->id();
            $newTemplate->save();

            // 复制步骤
            foreach ($template->steps as $step) {
                $newStep = $step->replicate();
                $newStep->sop_template_id = $newTemplate->id;
                $newStep->save();

                // 复制交互任务
                foreach ($step->interactiveTasks as $task) {
                    $newTask = $task->replicate();
                    $newTask->sop_step_id = $newStep->id;
                    $newTask->save();
                }
            }

            return $newTemplate;
        });
    }
}