require("dotenv").config();
const fs = require("fs");
const path = require("path");
const { MongoClient } = require("mongodb");

const DB_FILE = path.join(__dirname, "db.json");
const CSV_FILE = path.join(__dirname, "characters.csv");

// Helper to parse a CSV line, respecting double quotes
function parseCSVLine(line) {
  const result = [];
  let current = "";
  let inQuotes = false;

  for (let i = 0; i < line.length; i++) {
    const char = line[i];
    if (char === '"') {
      inQuotes = !inQuotes;
    } else if (char === "," && !inQuotes) {
      result.push(current.trim());
      current = "";
    } else {
      current += char;
    }
  }
  result.push(current.trim());
  return result;
}

// Generate template if CSV does not exist
if (!fs.existsSync(CSV_FILE)) {
  const templateContent = `Name,Base price,features,Image URL 1,Caption 1,Image URL 2,Caption 2,Image URL 3,CAption 3,Category
Goku,100,"Series: Dragon Ball; Rarity: SSR",AgACAg...,Goku Super Saiyan,AgACAg...,Goku Base Form,,,Anime
Naruto,80,"Series: Naruto; Rarity: SR",AgACAg...,Naruto Sage Mode,,,,,,Anime
Luffy,90,"Series: One Piece; Rarity: UR",AgACAg...,Luffy Gear 5,,,,,,Anime
`;
  fs.writeFileSync(CSV_FILE, templateContent, "utf8");
  console.log("📝 No 'characters.csv' file was found.");
  console.log("✅ Created a sample 'characters.csv' with the requested columns!");
  console.log("ℹ️ Open 'characters.csv' in Excel/Google Sheets, add your characters, and run this script again.");
  process.exit(0);
}

const fileContent = fs.readFileSync(CSV_FILE, "utf8");
const lines = fileContent.split(/\r?\n/).filter((line) => line.trim() !== "");

if (lines.length <= 1) {
  console.log("⚠️ The 'characters.csv' file is empty or only contains the header row.");
  process.exit(0);
}

// Skip header
const header = lines[0];
const dataLines = lines.slice(1);

let successCount = 0;
let failCount = 0;
const errors = [];
const importedChars = [];

dataLines.forEach((line, index) => {
  const lineNum = index + 2; // 1-indexed plus header line offset
  const parts = parseCSVLine(line);

  // We expect at least the first 3 columns
  if (parts.length < 3) {
    failCount++;
    errors.push(`Line ${lineNum}: Missing core columns (Expected Name, Base price, features)`);
    return;
  }

  const name = parts[0];
  const basePriceVal = parts[1];
  const featuresRaw = parts[2];
  const img1 = parts[3];
  const cap1 = parts[4];
  const img2 = parts[5];
  const cap2 = parts[6];
  const img3 = parts[7];
  const cap3 = parts[8];
  const category = parts[9];

  if (!name) {
    failCount++;
    errors.push(`Line ${lineNum}: Character Name is required.`);
    return;
  }

  const base_price = parseInt(basePriceVal, 10);
  if (isNaN(base_price) || base_price < 0) {
    failCount++;
    errors.push(`Line ${lineNum}: Invalid Base Price '${basePriceVal}'. Must be a non-negative number.`);
    return;
  }

  // Parse features (separated by ;)
  const features = featuresRaw
    ? featuresRaw
        .split(";")
        .map((f) => f.trim())
        .filter((f) => f.length > 0)
    : [];

  // Build image_url list
  const image_url = [];
  
  if (img1) {
    if (cap1) {
      image_url.push({ file_id: img1, caption: cap1 });
    } else {
      image_url.push(img1);
    }
  }
  
  if (img2) {
    if (cap2) {
      image_url.push({ file_id: img2, caption: cap2 });
    } else {
      image_url.push(img2);
    }
  }

  if (img3) {
    if (cap3) {
      image_url.push({ file_id: img3, caption: cap3 });
    } else {
      image_url.push(img3);
    }
  }

  // Generate unique character ID
  const id = `custom_${Date.now()}_${Math.floor(1000 + Math.random() * 9000)}`;

  importedChars.push({
    id,
    name,
    image_url,
    base_price,
    features,
    category: category || "",
    addedBy: "bulk_import"
  });

  successCount++;
});

async function saveImportedData() {
  if (successCount === 0) {
    console.log(`\n❌ Bulk Import Failed.`);
    return;
  }

  const mongoUri = process.env.MONGODB_URI;
  if (mongoUri) {
    console.log("\n🔌 Connecting to MongoDB for import...");
    let client;
    try {
      client = new MongoClient(mongoUri);
      await client.connect();
      const db = client.db();
      const collection = db.collection("bot_state");
      
      const record = await collection.findOne({ _id: "state" });
      let currentDB = record ? record.data : { customCharacters: [] };
      currentDB.customCharacters = currentDB.customCharacters || [];
      currentDB.customCharacters.push(...importedChars);
      
      await collection.updateOne(
        { _id: "state" },
        { $set: { data: currentDB } },
        { upsert: true }
      );
      
      console.log(`\n🎉 Bulk Import Complete (MongoDB Atlas)!`);
      console.log(`✅ Successfully imported *${successCount}* characters.`);
    } catch (err) {
      console.error("❌ Failed to save changes to MongoDB:", err.message || err);
      process.exit(1);
    } finally {
      if (client) await client.close();
    }
  } else {
    // Fallback to local db.json
    console.log("\n💾 Saving to local db.json...");
    let localDB = { customCharacters: [] };
    if (fs.existsSync(DB_FILE)) {
      try {
        localDB = JSON.parse(fs.readFileSync(DB_FILE, "utf8"));
      } catch (err) {
        console.error("❌ Failed to parse local db.json:", err);
        process.exit(1);
      }
    }
    localDB.customCharacters = localDB.customCharacters || [];
    localDB.customCharacters.push(...importedChars);
    
    try {
      fs.writeFileSync(DB_FILE, JSON.stringify(localDB, null, 2), "utf8");
      console.log(`\n🎉 Bulk Import Complete (local file)!`);
      console.log(`✅ Successfully imported *${successCount}* characters.`);
    } catch (err) {
      console.error("❌ Failed to save changes to db.json:", err);
      process.exit(1);
    }
  }

  if (failCount > 0) {
    console.log(`⚠️ Failed to import *${failCount}* rows due to formatting/validation errors:`);
    errors.forEach((err) => console.log(`  - ${err}`));
  }
}

saveImportedData();