import { defineConfig } from 'vite'
import react from '@vitejs/plugin-react'
import tailwindcss from '@tailwindcss/vite'

const MAX_TEAM_NAME_LENGTH = 80

function isAllowedApiUrl(req) {
  const url = new URL(req.url, 'http://localhost')
  const params = url.searchParams

  if (url.pathname === '/api/viewers' && (req.method === 'GET' || req.method === 'HEAD')) return true
  if (url.pathname === '/api/viewers/event' && req.method === 'POST') return true

  if (req.method !== 'GET' && req.method !== 'HEAD') return false

  if (url.pathname === '/api/tss/leaderboard/teams') {
    const keys = [...params.keys()]
    const limit = Number(params.get('limit') || 100)
    return keys.every((key) => key === 'limit') && Number.isInteger(limit) && limit >= 1 && limit <= 100
  }

  if (url.pathname === '/api/tss/teams/resolve') {
    const keys = [...params.keys()]
    const name = params.get('name') || ''
    return keys.every((key) => key === 'name') && name.length >= 2 && name.length <= MAX_TEAM_NAME_LENGTH
  }

  if ([...params.keys()].length) return false

  try {
    const match = url.pathname.match(/^\/api\/tss\/teams\/([^/]+)(?:\/(history|games))?$/)
    const teamName = match ? decodeURIComponent(match[1]) : ''
    return Boolean(teamName) && teamName.length <= MAX_TEAM_NAME_LENGTH
  } catch {
    return false
  }
}

function apiGuard() {
  return {
    name: 'api-guard',
    configureServer(server) {
      server.middlewares.use((req, res, next) => {
        if (!req.url?.startsWith('/api/')) {
          next()
          return
        }

        if (isAllowedApiUrl(req)) {
          next()
          return
        }

        res.writeHead(404, {
          'content-type': 'application/json; charset=utf-8',
          'x-content-type-options': 'nosniff',
        })
        res.end(JSON.stringify({ error: 'API route not found' }))
      })
    },
  }
}

export default defineConfig({
  plugins: [apiGuard(), react(), tailwindcss()],
  server: {
    host: '0.0.0.0',
    port: 3001,
    proxy: {
      '/api': {
        target: process.env.VITE_API_TARGET ?? 'http://localhost:6000',
        changeOrigin: true,
      },
      '/health': {
        target: process.env.VITE_API_TARGET ?? 'http://localhost:6000',
        changeOrigin: true,
      },
    },
  },
})