// src/pages/api/contribute/knowledgebase.ts
import type { APIRoute } from 'astro';
import { withAPIAuth } from '../../../utils/auth.js';
import { apiResponse, apiError, apiServerError, handleAPIRequest } from '../../../utils/api.js';
import { GitContributionManager } from '../../../utils/gitContributions.js';
import { z } from 'zod';

export const prerender = false;

const KnowledgebaseContributionSchema = z.object({
  toolName: z.string().optional().nullable().transform(val => val || undefined),
  title: z.string().optional().nullable().transform(val => val || undefined),
  description: z.string().optional().nullable().transform(val => val || undefined),
  content: z.string().optional().nullable().transform(val => val || undefined),
  externalLink: z.string().url().optional().nullable().catch(undefined),
  difficulty: z.enum(['novice', 'beginner', 'intermediate', 'advanced', 'expert']).optional().nullable().catch(undefined),
  categories: z.string().transform(str => {
    try { return JSON.parse(str); } catch { return []; }
  }).pipe(z.array(z.string()).default([])),
  tags: z.string().transform(str => {
    try { return JSON.parse(str); } catch { return []; }
  }).pipe(z.array(z.string()).default([])),
  uploadedFiles: z.string().transform(str => {
    try { return JSON.parse(str); } catch { return []; }
  }).pipe(z.array(z.any()).default([])),
  reason: z.string().optional().nullable().transform(val => val || undefined),
  contact: z.string().optional().nullable().transform(val => val || undefined)
});

interface KnowledgebaseContributionData {
  toolName?: string;
  title?: string;
  description?: string;
  content?: string;
  externalLink?: string;
  difficulty?: string;
  categories: string[];
  tags: string[];
  uploadedFiles: any[];
  reason?: string;
  contact?: string;
}

const rateLimitStore = new Map<string, { count: number; resetTime: number }>();
const RATE_LIMIT_WINDOW = 60 * 60 * 1000; // 1 hour
const RATE_LIMIT_MAX = 3; 

function checkRateLimit(userEmail: string): boolean {
  const now = Date.now();
  const userLimit = rateLimitStore.get(userEmail);
  
  if (!userLimit || now > userLimit.resetTime) {
    rateLimitStore.set(userEmail, { count: 1, resetTime: now + RATE_LIMIT_WINDOW });
    return true;
  }
  
  if (userLimit.count >= RATE_LIMIT_MAX) {
    return false;
  }
  
  userLimit.count++;
  return true;
}

function validateKnowledgebaseData(data: KnowledgebaseContributionData): { valid: boolean; errors?: string[] } {
  const hasContent = (data.content ?? '').trim().length > 0;
  const hasLink = (data.externalLink ?? '').trim().length > 0;
  const hasFiles = Array.isArray(data.uploadedFiles) && data.uploadedFiles.length > 0;
  const hasTitle = (data.title ?? '').trim().length > 0;
  const hasDescription = (data.description ?? '').trim().length > 0;
  
  if (!hasContent && !hasLink && !hasFiles && !hasTitle && !hasDescription) {
    return { 
      valid: false, 
      errors: ['Please provide at least a title, description, content, external link, or upload files'] 
    };
  }
  
  return { valid: true };
}

export const POST: APIRoute = async ({ request }) => {
  return await handleAPIRequest(async () => {
    const authResult = await withAPIAuth(request, 'contributions');
    if (authResult.authRequired && !authResult.authenticated) {
      return apiError.unauthorized();
    }

    const userEmail = authResult.session?.email || 'anon@anon.anon';

    if (!checkRateLimit(userEmail)) {
      return apiError.rateLimit('Rate limit exceeded. Please wait before submitting again.');
    }

    let formData;
    try {
      formData = await request.formData();
    } catch (error) {
      return apiError.badRequest('Invalid form data');
    }

    const rawData = Object.fromEntries(formData);

    let validatedData;
    try {
      validatedData = KnowledgebaseContributionSchema.parse(rawData);
    } catch (error) {
      if (error instanceof z.ZodError) {
        const errorMessages = error.errors.map(err => 
          `${err.path.join('.')}: ${err.message}`
        );
        return apiError.validation('Validation failed', errorMessages);
      }
      
      return apiError.badRequest('Invalid request data');
    }

    const contentValidation = validateKnowledgebaseData(validatedData);
    if (!contentValidation.valid) {
      return apiError.validation('Content validation failed', contentValidation.errors);
    }

    try {
      const gitManager = new GitContributionManager();
      const result = await gitManager.submitKnowledgebaseContribution({
        ...validatedData,
        submitter: userEmail
      });

      if (result.success) {
        console.log(`[KB CONTRIBUTION] "${validatedData.title || 'Article'}" by ${userEmail} - Issue: ${result.issueUrl}`);
        
        return apiResponse.created({
          success: true,
          message: result.message,
          issueUrl: result.issueUrl,
          issueNumber: result.issueNumber
        });
      } else {
        console.error(`[KB CONTRIBUTION FAILED] "${validatedData.title || 'Article'}" by ${userEmail}: ${result.message}`);
        
        return apiServerError.internal(`Contribution failed: ${result.message}`);
      }
    } catch (error) {
      console.error(`[KB GIT ERROR] "${validatedData.title || 'Article'}" by ${userEmail}:`, error);
      
      const errorMessage = error instanceof Error ? error.message : 'Git operation failed';
      return apiServerError.internal(`Submission failed: ${errorMessage}`);
    }

  }, 'Knowledgebase contribution processing failed');
};