server.js

import express from 'express';
import cors from 'cors';
import dotenv from 'dotenv';
import { fileURLToPath } from 'url';
import { dirname, join } from 'path';
import fetch from 'node-fetch';

// Initialize environment variables
dotenv.config();

const __filename = fileURLToPath(import.meta.url);
const __dirname = dirname(__filename);

const app = express();
const PORT = process.env.PORT || 3005;

// Middleware
app.use(cors());
app.use(express.json());
app.use(express.static(__dirname));

// API routes
app.post('/api/generate-ideas', async (req, res) => {
  try {
    const { prompt, category, language, audience, tone, knowledgeBase, customApiKey } = req.body;
    
    // Build a comprehensive LinkedIn idea generation system prompt
    let systemPrompt = `# LinkedIn Post Ideas Generator

You are a professional LinkedIn content strategist specializing in creating high-converting B2B content ideas. Your goal is to generate specific, actionable, and attention-grabbing LinkedIn post topics that would stop users from scrolling.

## Topic Style Guidelines

1. Be ULTRA SPECIFIC - Use exact numbers, percentages, timeframes and concrete results
2. Focus on outcomes and transformation - "How to achieve X result in Y timeframe"
3. Challenge common beliefs - "Why [common practice] is actually hurting your results"
4. Include "The exact..." or "The [number] ways..." to increase credibility
5. Address pain points directly - "Stop wasting money on..."
6. Use power words: ultimate, secrets, profitable, mistakes, killing, rejected, fix, converts

## Topic Format Examples for Business and Marketing
- "How to scale your [product/service] from $X to $Y per day profitably"
- "The exact [strategy/system] I use to get [specific result] on [platform]"
- "Why your [activity] is [negative outcome] (and how to fix it)"
- "Stop wasting money: The [number] biggest [platform] mistakes killing your profits"
- "How I decreased [metric] by [percentage] using [specific method]"

## Topic Format Examples for B2C Brands
- "How to turn your B2C brand into a customer magnet without spending a fortune on ads"
- "The secret psychology behind customer loyalty (and how smart brands use it)"
- "Why most B2C brands fail at [business goal] and the simple fix that changes everything"
- "[Number] proven ways to make your brand stand out in a crowded market (that your competition isn't using)"
- "The customer service mistake that's secretly killing your B2C brand's growth"
- "How to build a [aspect] that turns casual browsers into loyal customers"
- "The truth about [marketing concept] and why it matters more than ever for B2C brands"
- "What [famous brand] can teach you about consistent brand experience (and how to apply it to your business)"
- "The overlooked marketing channel that's bringing B2C brands massive ROI in 2025"
- "Why your ideal customers aren't buying (and the simple psychology fix that changes everything)"

## Topic Categories to Cover
- Tactical how-to's with specific outcomes
- Myth-busting posts that challenge industry norms
- Case studies with exact metrics and results
- Comparative analysis (X vs Y platform or strategy)
- Testing frameworks and performance optimization
- Specific strategies to improve key metrics (ROI, ROAS, CPA)
`;

    // Add user parameters to the system context
    let userContext = '';
    if (language) userContext += `Language: ${language}\n`;
    if (audience) userContext += `Target Audience: ${audience}\n`;
    if (category && category !== 'Any') userContext += `Category Focus: ${category}\n`;
    if (tone) userContext += `Content Tone: ${tone}\n`;
    if (knowledgeBase && knowledgeBase.trim() !== '') userContext += `\nIncorporate this knowledge: ${knowledgeBase}\n`;
    
    // Define the specific request based on user input
    let specificRequest = '';
    if (prompt) {
      specificRequest = `Generate 10 LinkedIn post ideas related to: ${prompt}.\n\nCreate a mix of ideas using BOTH the Business/Marketing formats AND the B2C Brand formats from the examples above. Each idea should follow a different format pattern for maximum variety.\n\nMake these ideas highly specific, results-focused, and attention-grabbing. Include exact numbers, percentages, and concrete outcomes where appropriate. Each idea should be a complete, compelling headline that would make someone stop scrolling.`;
    } else {
      specificRequest = `Generate 10 diverse LinkedIn post ideas for the target audience specified.\n\nCreate a mix of ideas using BOTH the Business/Marketing formats AND the B2C Brand formats from the examples above. Use 5 ideas from each category and ensure each follows a different pattern.\n\nThe ideas should cover different aspects like:\n- Performance optimization and ROI improvements\n- Common mistakes and their solutions\n- Psychological insights that drive customer behavior\n- Comparison of different strategies or platforms\n- Case studies with specific metrics and results\n- Step-by-step frameworks and methodologies\n- Brand differentiation strategies\n- Customer retention and loyalty techniques\n\nMake each idea highly specific, results-focused, and in line with the topic format examples above. Use exact numbers, percentages, timeframes, and clear outcomes. Each idea should be a complete, compelling headline that would make someone stop scrolling.`;
    }
    
    // Combine all parts into the final prompt
    let ideaPrompt = `${systemPrompt}\n\n## Your Assignment\n${userContext}\n${specificRequest}\n\nFormat as a simple numbered list with one idea per line. Don't include any explanations or additional text.`;
    
    // Use custom API key if provided, otherwise use the server's key
    const apiKey = customApiKey || process.env.ANTHROPIC_API_KEY;
    
    const response = await fetch('https://api.anthropic.com/v1/messages', {
      method: 'POST',
      headers: {
        'Content-Type': 'application/json',
        'x-api-key': apiKey,
        'anthropic-version': '2023-06-01'
      },
      body: JSON.stringify({
        model: 'claude-3-7-sonnet-20250219',
        max_tokens: 300,
        messages: [
          { role: 'user', content: ideaPrompt }
        ]
      })
    });

    if (!response.ok) {
      const errorData = await response.json();
      throw new Error(errorData.error?.message || 'API request failed');
    }

    const data = await response.json();
    console.log('Claude API response:', JSON.stringify(data));
    const content = data.content[0].text;
    console.log('Content extracted:', content);
    
    // Parse the numbered list into an array of ideas
    // First, split by newline
    const lines = content.split('\n');
    console.log('Split lines:', lines);
    
    // Then filter for numbered lines and clean them up
    const ideasArray = lines
      .filter(line => /^\d+\./.test(line.trim()))
      .map(line => line.replace(/^\d+\.\s*/, '').trim());
      
    console.log('Extracted ideas:', ideasArray);
    
    // If no ideas were found using the numbered list format, try to extract any lines that look meaningful
    if (ideasArray.length === 0) {
      console.log('No numbered ideas found, trying fallback extraction');
      const fallbackIdeas = lines
        .map(line => line.trim())
        .filter(line => line.length > 15 && !line.startsWith('You are') && !line.includes('Generate 5'));
      
      console.log('Fallback ideas:', fallbackIdeas);
      
      if (fallbackIdeas.length > 0) {
        res.json({ ideas: fallbackIdeas });
        return;
      }
      
      // If still no ideas, create some default ones
      res.json({ 
        ideas: [
          "How to Boost Customer Engagement with Personalized Marketing",
          "5 Social Media Trends B2C Brands Can't Ignore in 2025",
          "Building Customer Trust: From First Click to Lifetime Loyalty",
          "Data-Driven Strategies to Understand Your B2C Customers Better",
          "Creating Authentic Brand Stories That Resonate with Modern Consumers"
        ] 
      });
      return;
    }
    
    res.json({ ideas: ideasArray });
  } catch (error) {
    console.error('Error:', error);
    res.status(500).json({ error: error.message });
  }
});

app.post('/api/generate-post', async (req, res) => {
  try {
    const { category, language, audience, tone, topicType, topicContent, knowledgeBase, customApiKey } = req.body;
    
    // LinkedIn Post Generator System Prompt
    const linkedInSystemPrompt = `# LinkedIn Post Generator System Prompt

You are a professional LinkedIn content creator AI that specializes in creating high-converting B2B LinkedIn posts. Your goal is to create LinkedIn posts that generate inbound leads, increase engagement, and ultimately drive conversions for your user's business.

## Core Content Philosophy

Follow the CAV framework for all posts:
- **Consumable**: Create one-sentence paragraphs with simple formatting. Each line should be 1-2 sentences maximum. Use ample spacing between paragraphs.
- **Actionable**: Provide steps users can implement within 24 hours. Focus on immediate, practical advice.
- **Valuable**: Deliver information people would potentially pay for. Solve real problems.

## Post Types

You can create the following types of posts:

### 1. Lead Magnet Posts
Purpose: To generate comments, connections, and collect leads.
Structure:
- Hook: Bold claim about outcome + timeframe + mechanism
- Problem/pain points that the resource solves
- Proof/expertise (why should they listen to you)
- What's in the resource (use specific numbers/percentages)
- Call to action (connect + comment specific word)

### 2. Value/Technical Posts
Purpose: To demonstrate expertise and build trust.
Structure:
- Hook: Challenge a common belief or ask a provocative question
- What & Why: High-level value and overall advice
- How: Step-by-step process with actionable insights
- Subtle product/service mention (if relevant)
- Simple question as call to action

### 3. Case Study/Social Proof Posts
Purpose: To provide evidence that your solution works.
Structure:
- Hook: Specific results achieved in specific timeframe
- Previous situation (pain points)
- Process used to achieve results
- Specific outcomes with exact numbers
- Key takeaways or lessons learned
- Call to action

### 4. Setup Call Posts
Purpose: To get people to book calls directly.
Structure:
- Hook: Bold claim about what they can achieve
- Simple step-by-step process
- Mention your product/service as part of the solution
- Soft call to action offering to set it up for them

### 5. Building In Public Posts
Purpose: To build connection and show progress.
Structure:
- Previous milestone
- Current situation
- Future goals
- What makes your approach different
- Ask for feedback

## Hook Creation Guidelines

The hook (first 3 lines) is the most critical part of your LinkedIn post. LinkedIn only shows the first 3 lines before "see more," so your hook must:

1. Stop people from scrolling
2. Get them to click "see more"

Effective hook strategies:
- Bold claims with specific outcomes ("LinkedIn will make me 100k a month in 2025")
- Questions that trigger curiosity ("Want to know how I generated 487 calls in 30 days?")
- Challenging common beliefs ("LinkedIn content agencies are under attack")
- Specific timeframes + results ("I wrote 30 posts in 10 minutes")
- Personal stories with outcomes ("I built my entire business using this LinkedIn funnel")

## Formatting Rules

1. Keep paragraphs to 1-2 sentences maximum
2. Use ample spacing between paragraphs
3. Use a mix of short and medium-length sentences
4. For lists, use line breaks rather than numbers/bullets when possible
5. Use emojis sparingly (0-2 per post)
6. For lead magnet posts, always include instructions to "comment [WORD] and connect with me"
7. Total post length: 1200-1500 characters is ideal

## Media Recommendations

Suggest incorporating:
- Success screenshots (calendar bookings, revenue, etc.)
- Simple graphics showing results or process
- Before/after comparisons
- Preview of the resource being shared`;

    // User input parameters
    let prompt = `${linkedInSystemPrompt}\n\n# Post Parameters\n`;
    prompt += `Language: ${language}\n`;
    prompt += `Target audience: ${audience}\n`;
    prompt += `Tone: ${tone}\n`;
    
    // Add knowledge base if provided
    if (knowledgeBase && knowledgeBase.trim() !== '') {
      prompt += `\nAdditional Knowledge to Incorporate:\n${knowledgeBase}\n`;    
    }
    
    if (category !== 'Any') {
      prompt += `Post category: ${category}\n`;
    }

    if (topicType === 'custom') {
      prompt += `Topic: ${topicContent}\n`;
    } else {
      prompt += `Topic: ${topicContent}\n`;
    }

    // Select post type based on category
    let postType = "Value/Technical Posts";
    if (category === "Professional advice") {
      postType = "Value/Technical Posts";
    } else if (category === "Case study - client" || category === "Case study - personal") {
      postType = "Case Study/Social Proof Posts";
    } else if (category === "List of tips") {
      postType = "Lead Magnet Posts";
    } else if (category === "Personal story") {
      postType = "Building In Public Posts";
    }
    
    prompt += `Post Type: ${postType}\n`;
    prompt += `\nPlease create a complete LinkedIn post following the guidelines above. Include hook, body, and call to action. Make it engaging and designed to attract new followers.`;
    
    // Use custom API key if provided, otherwise use the server's key
    const apiKey = customApiKey || process.env.ANTHROPIC_API_KEY;
    
    const response = await fetch('https://api.anthropic.com/v1/messages', {
      method: 'POST',
      headers: {
        'Content-Type': 'application/json',
        'x-api-key': apiKey,
        'anthropic-version': '2023-06-01'
      },
      body: JSON.stringify({
        model: 'claude-3-opus-20240229',
        max_tokens: 1000,
        messages: [
          { role: 'user', content: prompt }
        ]
      })
    });

    if (!response.ok) {
      const errorData = await response.json();
      throw new Error(errorData.error?.message || 'API request failed');
    }

    const data = await response.json();
    res.json({ post: data.content[0].text });
  } catch (error) {
    console.error('Error:', error);
    res.status(500).json({ error: error.message });
  }
});

// Start server
app.listen(PORT, () => {
  console.log(`Server running on http://localhost:${PORT}`);
});