import fs from 'fs/promises'
import path from 'path'
import http from 'http'
import stream from 'stream'
import { URL } from 'url'
import { defaults } from './helper.mjs'

export default function Client(port, opts) {
  this.options = defaults(opts, {})
  this.prefix = `http://localhost:${port}`
}

Client.prototype.customRequest = function(method = 'GET', path, body, options = {}) {
  if (path.slice(0, 4) !== 'http') {
    path = this.prefix + path
  }
  let urlObj = new URL(path)

  return new Promise((resolve, reject) => {
    const opts = defaults(defaults(options, {
      method: method,
      timeout: 500,
      protocol: urlObj.protocol,
      username: urlObj.username,
      password: urlObj.password,
      host: urlObj.hostname,
      port: Number(urlObj.port),
      path: urlObj.pathname + urlObj.search,
      headers: {},
    }))

    if (options.agent) {
      opts.agent = options.agent
    }

    // opts.agent = agent

    const req = http.request(opts)

    req.on('error', (err) => {
      reject(err)
    })
    req.on('timeout', function() {
      req.destroy()
      reject(new Error(`Request ${method} ${path} timed out`))
    })
    req.on('response', res => {
      let output = ''
      if (options.toPipe) {
        return stream.pipeline(res, options.toPipe, function(err) {
          if (err) {
            return reject(err)
          }
          resolve()
        })
      } else {
        res.setEncoding('utf8')

        res.on('data', function (chunk) {
          output += chunk.toString()
        })
      }

      res.on('end', function () {
        if (options.getRaw) {
          output = {
            status: res.statusCode,
            data: output,
            headers: res.headers,
          }
        } else {
          if (!output) return resolve(null)
          try {
            output = JSON.parse(output)
          } catch (e) {
            return reject(new Error(`${e.message} while decoding: ${output}`))
          }
        }
        if (!options.getRaw && output.status && typeof(output.status) === 'number') {
          let err = new Error(`Request failed [${output.status}]: ${output.message}`)
          err.body = output
          return reject(err)
        }
        resolve(output)
      })
    })

    if (opts.returnRequest) {
      return resolve(req)
    }
    
    if (body) {
      req.write(body)
    }
    req.end()
    return req
  })
}

Client.prototype.get = function(url = '/') {
  return this.customRequest('GET', url, null)
}

Client.prototype.post = function(url = '/', body = {}) {
  let parsed = JSON.stringify(body)
  return this.customRequest('POST', url, parsed, {
    headers: {
      'Content-Type': 'application/json',
      'Content-Length': parsed.length,
    },
  })
}

Client.prototype.del = function(url = '/', body = {}) {
  return this.customRequest('DELETE', url, JSON.stringify(body))
}

const random = (length = 8) => {
  // Declare all characters
  let chars = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789';
  // Pick characers randomly
  let str = '';
  for (let i = 0; i < length; i++) {
      str += chars.charAt(Math.floor(Math.random() * chars.length));
  }
  return str;
}

Client.prototype.upload = function(url, files, method = 'POST', body = {}, overrideType = null) {
  const boundary = `---------${random(32)}`
  const crlf = '\r\n'
  let upload = files

  if (typeof(upload) === 'string') {
    upload = {
      file: files
    }
  }
  let keys = Object.keys(upload)
  let uploadBody = []

  return Promise.all(keys.map(key => {
    let file = upload[key]
    return fs.readFile(file).then(data => {
      const filename = path.basename(file)

      uploadBody.push(Buffer.from(
        `${crlf}--${boundary}${crlf}`
         + `Content-Disposition: form-data; name="${key}"; filename="${filename}"`
         + (overrideType ? crlf + `Content-Type: ${overrideType}`: '')
         + crlf
         + crlf
      ))
      uploadBody.push(data)
    })
  }))
  .then(() => {
    uploadBody.push(
      Buffer.concat(Object.keys(body).map(function(key) {
        return Buffer.from(''
          + `${crlf}--${boundary}${crlf}`
          + `Content-Disposition: form-data; name="${key}"` + crlf + crlf
          + JSON.stringify(body[key])
        )
      }))
    )
    uploadBody.push(Buffer.from(`${crlf}--${boundary}--`))

    let multipartBody = Buffer.concat(uploadBody)

    return this.customRequest(method, url, multipartBody, {
      timeout: 5000,
      headers: {
        'Content-Type': 'multipart/form-data; boundary=' + boundary,
        'Content-Length': multipartBody.length,
      },
    })
  })
}