import { Command } from 'commander';
import chalk from 'chalk';
import { findNodeByPrefix, getNodeAtTime, getCurrentVersion } from '../../core/store';
import { getConnections } from '../../core/graph';

export const showCommand = new Command('show')
  .argument('<id>', 'Node ID (or prefix)')
  .option('--format <fmt>', 'Output format: text or json', 'text')
  .option('--at <timestamp>', 'Show node at a specific point in time (ISO date or timestamp)')
  .description('Show a node and its connections')
  .action(async (idRaw: string, opts) => {
    const node = findNodeByPrefix(idRaw);
    if (!node) {
      console.error(chalk.red(`Node not found: ${idRaw}`));
      process.exit(1);
    }

    // If --at is specified, show historical state
    if (opts.at) {
      const ts = isNaN(Number(opts.at)) ? Date.parse(opts.at) : Number(opts.at);
      if (isNaN(ts)) {
        console.error(chalk.red('Invalid timestamp format. Use ISO date (e.g., 2024-01-01) or Unix timestamp.'));
        process.exit(1);
      }

      const historical = getNodeAtTime(node.id, ts);
      if (!historical) {
        console.error(chalk.red('No version found for the specified time.'));
        process.exit(1);
      }

      if (opts.format === 'json') {
        console.log(JSON.stringify(historical, null, 2));
        return;
      }

      console.log(chalk.dim(`Viewing historical state at: ${new Date(ts).toLocaleString()}`));
      console.log('');
      console.log(chalk.bold.cyan(`[${historical.kind}] ${historical.title}`));
      console.log(`ID:      ${historical.id}`);
      console.log(`Version: v${historical.version}`);
      if (historical.status) console.log(`Status:  ${historical.status}`);
      if (historical.tags.length) console.log(`Tags:    ${historical.tags.join(', ')}`);
      console.log(`Valid:   ${new Date(historical.validFrom).toLocaleString()} - ${historical.validUntil ? new Date(historical.validUntil).toLocaleString() : 'current'}`);
      if (historical.content) console.log(`\n${historical.content}`);

      // Render structured sections
      if (historical.metadata?.sections && Array.isArray(historical.metadata.sections)) {
        for (const sec of historical.metadata.sections) {
          console.log(`\n${chalk.bold(`-- ${sec.label} --`)}`);
          if (sec.body) console.log(sec.body);
        }
      }
      return;
    }

    const conns = getConnections(node.id);
    const version = getCurrentVersion(node.id);

    if (opts.format === 'json') {
      console.log(JSON.stringify({ ...node, embedding: undefined, version, connections: conns }, null, 2));
      return;
    }

    console.log(chalk.bold.cyan(`[${node.kind}] ${node.title}`));
    console.log(`ID:      ${node.id}`);
    console.log(`Version: v${version}`);
    if (node.status) console.log(`Status:  ${node.status}`);
    if (node.tags.length) console.log(`Tags:    ${node.tags.join(', ')}`);
    console.log(`Created: ${new Date(node.createdAt).toLocaleString()}`);
    console.log(`Updated: ${new Date(node.updatedAt).toLocaleString()}`);
    if (node.isStale) console.log(chalk.red('STALE'));
    if (node.content) console.log(`\n${node.content}`);

    // Render structured sections
    if (node.metadata?.sections && Array.isArray(node.metadata.sections)) {
      for (const sec of node.metadata.sections) {
        console.log(`\n${chalk.bold(`── ${sec.label} ──`)}`);
        if (sec.body) console.log(sec.body);
      }
    }

    // Inline children (outgoing 'contains' edges)
    const children = conns.outgoing.filter(c => c.type === 'contains');
    if (children.length) {
      console.log(chalk.bold('\nChildren:'));
      for (const c of children) {
        console.log(`  ${c.node.id.slice(0, 8)} [${c.node.kind}] ${c.node.title}`);
      }
    }

    if (conns.outgoing.length) {
      console.log(chalk.bold('\nOutgoing:'));
      for (const c of conns.outgoing) {
        console.log(`  ${chalk.dim(`-[${c.type}]->`)} [${c.node.kind}] ${c.node.title} (${c.node.id.slice(0, 8)})`);
      }
    }

    if (conns.incoming.length) {
      console.log(chalk.bold('\nIncoming:'));
      for (const c of conns.incoming) {
        console.log(`  [${c.node.kind}] ${c.node.title} (${c.node.id.slice(0, 8)}) ${chalk.dim(`-[${c.type}]->`)} this`);
      }
    }
  });