import { marked, Renderer } from 'marked'
import hljs from 'highlight.js/lib/core'

// Import only common languages
import javascript from 'highlight.js/lib/languages/javascript'
import typescript from 'highlight.js/lib/languages/typescript'
import bash from 'highlight.js/lib/languages/bash'
import json from 'highlight.js/lib/languages/json'
import yaml from 'highlight.js/lib/languages/yaml'
import markdown from 'highlight.js/lib/languages/markdown'
import css from 'highlight.js/lib/languages/css'
import xml from 'highlight.js/lib/languages/xml'
import python from 'highlight.js/lib/languages/python'
import rust from 'highlight.js/lib/languages/rust'
import go from 'highlight.js/lib/languages/go'

hljs.registerLanguage('javascript', javascript)
hljs.registerLanguage('js', javascript)
hljs.registerLanguage('typescript', typescript)
hljs.registerLanguage('ts', typescript)
hljs.registerLanguage('bash', bash)
hljs.registerLanguage('sh', bash)
hljs.registerLanguage('shell', bash)
hljs.registerLanguage('json', json)
hljs.registerLanguage('yaml', yaml)
hljs.registerLanguage('yml', yaml)
hljs.registerLanguage('markdown', markdown)
hljs.registerLanguage('md', markdown)
hljs.registerLanguage('css', css)
hljs.registerLanguage('html', xml)
hljs.registerLanguage('xml', xml)
hljs.registerLanguage('python', python)
hljs.registerLanguage('py', python)
hljs.registerLanguage('rust', rust)
hljs.registerLanguage('rs', rust)
hljs.registerLanguage('go', go)

// Custom renderer with syntax highlighting
const renderer = new Renderer()

renderer.code = function({ text, lang }: { text: string; lang?: string }) {
  let highlighted: string
  if (lang && hljs.getLanguage(lang)) {
    try {
      highlighted = hljs.highlight(text, { language: lang }).value
    } catch {
      highlighted = escapeHtml(text)
    }
  } else {
    // No auto-detect, just escape
    highlighted = escapeHtml(text)
  }
  return `<pre><code class="hljs">${highlighted}</code></pre>`
}

function escapeHtml(str: string): string {
  return str
    .replace(/&/g, '&amp;')
    .replace(/</g, '&lt;')
    .replace(/>/g, '&gt;')
}

marked.setOptions({
  breaks: true,
  gfm: true,
  renderer,
})

export function renderMarkdown(content: string): string {
  return marked.parse(content) as string
}