fix bugs and improve code quality

Author: siansiansu

README.md

@@ -1,61 +1,128 @@
-# eBird client for Go
+# go-ebird: eBird API Client for Go
 
-[![GoDoc](https://godoc.org/github.com/siansiansu/go-ebird?status.svg)](http://godoc.org/github.com/siansiansu/go-ebird) [![License: MIT](https://img.shields.io/badge/License-MIT-yellow.svg)](https://opensource.org/licenses/MIT)
+[![GoDoc](https://godoc.org/github.com/siansiansu/go-ebird?status.svg)](http://godoc.org/github.com/siansiansu/go-ebird)
+[![License: MIT](https://img.shields.io/badge/License-MIT-yellow.svg)](https://opensource.org/licenses/MIT)
+[![Go Report Card](https://goreportcard.com/badge/github.com/siansiansu/go-ebird)](https://goreportcard.com/report/github.com/siansiansu/go-ebird)
 
 ## Overview
 
-go-ebird is a Go client library designed for the eBird API. This library enables developers to seamlessly integrate bird observation data from eBird into their Go applications.
+go-ebird is a comprehensive Go client library for the eBird API. It provides an easy-to-use interface for developers to integrate bird observation data from eBird into their Go applications.
 
 ## Features
 
-- **Data Retrieval**: Access bird observation data from eBird effortlessly.
-- **Flexible Filtering**: Filter data based on parameters such as location, date, and species.
-- **Easy Integration**: Integrate eBird data seamlessly into your Go applications.
+- **Comprehensive Data Access**: Retrieve various types of bird observation data, including recent observations, notable sightings, and checklists.
+- **Flexible Filtering**: Filter data based on location, date, species, and more.
+- **Robust Error Handling**: Clear error messages and proper handling of API rate limits.
+- **Customizable Client**: Configure timeout, base URL, and other HTTP client options.
+- **Full API Coverage**: Support for all major eBird API endpoints.
 
 ## Installation
 
-Install `go-ebird` using `go get`:
+Install go-ebird using `go get`:
 
 ```shell
 go get -u github.com/siansiansu/go-ebird
 ```
 
-## Usage
+## Quick Start
+
+Here's a simple example to get you started:
 
 ```go
 package main
 
 import (
-  "context"
-  "fmt"
+    "context"
+    "fmt"
+    "log"
 
-  "github.com/siansiansu/go-ebird"
+    "github.com/siansiansu/go-ebird"
 )
 
 func main() {
-  var ctx = context.Background()
-  client, err := ebird.NewClient("YOUR_EBIRD_API_KEY")
-  if err != nil {
-    panic(err)
-  }
-  r, err := client.RecentNotableObservationsInRegion(ctx, "TW")
-  if err != nil {
-    panic(err)
-  }
-  for _, e := range r {
-    fmt.Println(e.ComName, e.LocName, e.HowMany)
-  }
+    client, err := ebird.NewClient("YOUR_EBIRD_API_KEY")
+    if err != nil {
+        log.Fatalf("Failed to create client: %v", err)
+    }
+
+    observations, err := client.RecentObservationsInRegion(context.Background(), "US-NY", ebird.MaxResults(5))
+    if err != nil {
+        log.Fatalf("Failed to get observations: %v", err)
+    }
+
+    for _, obs := range observations {
+        fmt.Printf("%s spotted at %s\n", obs.ComName, obs.LocName)
+    }
 }
 ```
 
-Remember to replace `"YOUR_EBIRD_API_KEY"` with your actual eBird API key. You can obtain an API key by creating an account on the [eBird website](https://ebird.org/api/keygen).
+## Detailed Usage
+
+Check out the [examples directory](./examples/) for more detailed usage examples, including:
+
+- Retrieving notable observations
+- Getting nearby hotspots
+- Fetching recent checklists
+- Accessing taxonomy information
+
+## API Endpoints
+
+go-ebird supports all major eBird API endpoints, including:
+
+- Observations
+- Hotspots
+- Taxonomy
+- Checklists
+- Region information
+
+Refer to the [GoDoc](https://pkg.go.dev/github.com/siansiansu/go-ebird) for a complete list of supported endpoints and their usage.
+
+## Configuration
+
+You can configure the client with various options:
+
+```go
+client, err := ebird.NewClient(
+    "YOUR_EBIRD_API_KEY",
+    ebird.WithBaseURL("https://api.ebird.org/v2/"),
+    ebird.WithHTTPClient(&http.Client{Timeout: 30 * time.Second}),
+    ebird.WithAcceptLanguage("en"),
+)
+```
 
-Refer to the [GoDoc](https://pkg.go.dev/github.com/siansiansu/go-ebird) page for comprehensive documentation and more examples.
+## Rate Limiting
+
+The eBird API has rate limits. This client does not automatically handle rate limiting, so be sure to implement appropriate backoff and retry logic in your application.
 
 ## Contributing
 
-Contributions are welcome! Report bugs or request features by opening an issue. If you want to contribute code, fork the repository and submit a pull request.
+Contributions are welcome! Here's how you can contribute:
+
+1. Fork the repository
+2. Create your feature branch (`git checkout -b feature/AmazingFeature`)
+3. Commit your changes (`git commit -m 'Add some AmazingFeature'`)
+4. Push to the branch (`git push origin feature/AmazingFeature`)
+5. Open a Pull Request
+
+Please ensure your code adheres to the existing style and includes appropriate tests.
+
+## Testing
+
+Run the tests using:
+
+```shell
+go test -v ./...
+```
 
 ## License
 
 This project is licensed under the MIT License - see the [LICENSE](./LICENSE) file for details.
+
+## Acknowledgments
+
+- Thanks to the eBird team for providing the API
+- Inspired by other excellent Go API clients
+
+## Support
+
+If you encounter any issues or have questions, please [open an issue](https://github.com/siansiansu/go-ebird/issues/new) on GitHub.