#!/usr/bin/env node
/**
 * Rich List Scanner for Triangles Blockchain
 * Scans all blocks, tracks address balances, generates rich list
 */

const axios = require('axios');
const fs = require('fs');
const path = require('path');

const RPC_URL = 'http://127.0.0.1:19112';
const RPC_USER = 'trianglesrpc';
const RPC_PASS = '2KVK2FvLZBW9Hxv4a2Uj3dMRDAXdh4ei6S5tdZ3z2Mme';

const DATA_DIR = path.join(__dirname, 'data');
const STATE_FILE = path.join(DATA_DIR, 'scanner-state.json');
const RICHLIST_FILE = path.join(DATA_DIR, 'richlist.json');
const BALANCES_FILE = path.join(DATA_DIR, 'balances.json');

const BATCH_SIZE = 100; // Process 100 blocks per batch
const SAVE_INTERVAL = 500; // Save state every 500 blocks

// Ensure data directory exists
if (!fs.existsSync(DATA_DIR)) {
  fs.mkdirSync(DATA_DIR, { recursive: true });
}

// RPC helper
async function rpc(method, params = []) {
  try {
    const response = await axios.post(RPC_URL, {
      jsonrpc: '1.0',
      id: 'richlist-scanner',
      method,
      params
    }, {
      auth: { username: RPC_USER, password: RPC_PASS },
      timeout: 30000
    });
    return response.data.result;
  } catch (error) {
    console.error(`RPC error (${method}):`, error.response?.data || error.message);
    throw error;
  }
}

// Load scanner state
function loadState() {
  if (fs.existsSync(STATE_FILE)) {
    return JSON.parse(fs.readFileSync(STATE_FILE, 'utf8'));
  }
  return {
    lastProcessedBlock: 0,
    chainHeight: 0,
    totalAddresses: 0,
    lastUpdate: new Date().toISOString()
  };
}

// Save scanner state
function saveState(state) {
  fs.writeFileSync(STATE_FILE, JSON.stringify(state, null, 2));
}

// Load balances
function loadBalances() {
  if (fs.existsSync(BALANCES_FILE)) {
    return new Map(Object.entries(JSON.parse(fs.readFileSync(BALANCES_FILE, 'utf8'))));
  }
  return new Map();
}

// Save balances
function saveBalances(balances) {
  const obj = Object.fromEntries(balances);
  fs.writeFileSync(BALANCES_FILE, JSON.stringify(obj, null, 2));
}

// Generate rich list from balances
function generateRichList(balances) {
  const list = Array.from(balances.entries())
    .map(([address, balance]) => ({ address, balance }))
    .filter(item => item.balance > 0)
    .sort((a, b) => b.balance - a.balance)
    .slice(0, 1000); // Top 1000

  fs.writeFileSync(RICHLIST_FILE, JSON.stringify(list, null, 2));
  console.log(`Rich list generated: ${list.length} addresses`);
  return list;
}

// Process a single block
async function processBlock(height, balances) {
  try {
    const blockHash = await rpc('getblockhash', [height]);
    const block = await rpc('getblock', [blockHash, true]);

    for (const txid of block.tx) {
      // txid might be an object in some RPC versions, extract string if needed
      const txidStr = typeof txid === 'string' ? txid : txid.txid || txid;
      const tx = await rpc('getrawtransaction', [txidStr, 1]);

      // Subtract inputs (spent)
      if (tx.vin) {
        for (const input of tx.vin) {
          if (input.txid && input.vout !== undefined) {
            try {
              const prevTx = await rpc('getrawtransaction', [input.txid, 1]);
              const prevOut = prevTx.vout[input.vout];
              if (prevOut && prevOut.scriptPubKey && prevOut.scriptPubKey.addresses) {
                for (const addr of prevOut.scriptPubKey.addresses) {
                  const current = balances.get(addr) || 0;
                  balances.set(addr, current - prevOut.value);
                }
              }
            } catch (e) {
              // Coinbase or missing tx, skip
            }
          }
        }
      }

      // Add outputs (received)
      if (tx.vout) {
        for (const output of tx.vout) {
          if (output.scriptPubKey && output.scriptPubKey.addresses) {
            for (const addr of output.scriptPubKey.addresses) {
              const current = balances.get(addr) || 0;
              balances.set(addr, current + output.value);
            }
          }
        }
      }
    }

    return true;
  } catch (error) {
    console.error(`Error processing block ${height}:`, error.message);
    return false;
  }
}

// Main scanning loop
async function scan() {
  console.log('Starting rich list scanner...');
  
  const state = loadState();
  const balances = loadBalances();

  console.log(`Resuming from block ${state.lastProcessedBlock}`);
  console.log(`Current addresses tracked: ${balances.size}`);

  while (true) {
    try {
      // Get current chain height
      const info = await rpc('getinfo');
      state.chainHeight = info.blocks;

      if (state.lastProcessedBlock >= state.chainHeight) {
        console.log('Caught up! Waiting for new blocks...');
        await new Promise(resolve => setTimeout(resolve, 60000)); // Wait 1 minute
        continue;
      }

      const targetBlock = Math.min(state.lastProcessedBlock + BATCH_SIZE, state.chainHeight);
      
      console.log(`Processing blocks ${state.lastProcessedBlock + 1} to ${targetBlock} (${state.chainHeight} total)`);

      for (let height = state.lastProcessedBlock + 1; height <= targetBlock; height++) {
        const success = await processBlock(height, balances);
        
        if (success) {
          state.lastProcessedBlock = height;
          state.totalAddresses = balances.size;
          state.lastUpdate = new Date().toISOString();

          if (height % SAVE_INTERVAL === 0 || height === state.chainHeight) {
            saveState(state);
            saveBalances(balances);
            generateRichList(balances);
            console.log(`Progress: ${height}/${state.chainHeight} (${(height/state.chainHeight*100).toFixed(2)}%)`);
          }
        } else {
          console.log(`Retrying block ${height} in 5 seconds...`);
          await new Promise(resolve => setTimeout(resolve, 5000));
          break;
        }
      }

      // Small delay between batches
      await new Promise(resolve => setTimeout(resolve, 1000));

    } catch (error) {
      console.error('Scanner error:', error);
      await new Promise(resolve => setTimeout(resolve, 10000)); // Wait 10 seconds on error
    }
  }
}

// Handle graceful shutdown
process.on('SIGINT', () => {
  console.log('Shutting down scanner...');
  process.exit(0);
});

process.on('SIGTERM', () => {
  console.log('Shutting down scanner...');
  process.exit(0);
});

// Start scanning
scan().catch(console.error);