package api_gen

import (
	"os"
	"path/filepath"
	"text/template"
)

func generateJSClient(outputDir string, pkg *APIPackage) error {
	tmpl := `// Code generated by api_gen. DO NOT EDIT.

/**
 * Auto-generated API Client
 * Generated from: {{ .PkgPath }}
 */

class APIClient {
  constructor(baseURL = '', options = {}) {
    this.baseURL = baseURL;
    this.timeout = options.timeout || 30000;
    this.headers = options.headers || {};
    this.onUnauthorized = options.onUnauthorized || null;
  }

  async request(method, path, body = null) {
    const url = this.baseURL + path;
    const controller = new AbortController();
    const timeoutId = setTimeout(() => controller.abort(), this.timeout);

    try {
      const options = {
        method,
        headers: {
          'Content-Type': 'application/json',
          ...this.headers
        },
        credentials: 'same-origin',
        signal: controller.signal
      };

      if (body !== null) {
        options.body = JSON.stringify(body);
      }

      const response = await fetch(url, options);
      clearTimeout(timeoutId);

      if (!response.ok) {
        let parsed = null;
        try { parsed = await response.json(); } catch (_) {}
        const err = new Error(` + "`Request failed with status ${response.status}`" + `);
        err.status = response.status;
        err.response = parsed;
        if (response.status === 401 && this.onUnauthorized) {
          this.onUnauthorized(err);
        }
        throw err;
      }

      const text = await response.text();
      return text ? JSON.parse(text) : null;
    } catch (error) {
      clearTimeout(timeoutId);
      if (error.name === 'AbortError') {
        throw new Error('Request timeout');
      }
      throw error;
    }
  }

{{ range .Endpoints }}
  async {{.Name}}(req) {
    return this.request('{{.Method}}', '{{.Path}}', req);
  }
{{ end }}
}

if (typeof module !== 'undefined' && module.exports) {
  module.exports = APIClient;
}

if (typeof window !== 'undefined') {
  window.APIClient = APIClient;
}
`

	tmplObj := template.Must(template.New("jsclient").Parse(tmpl))

	f, err := os.Create(filepath.Join(outputDir, "client.js"))
	if err != nil {
		return err
	}
	defer f.Close()

	return tmplObj.Execute(f, pkg)
}