package gogpt_test

import (
	"bytes"
	"errors"
	"io"
	"mime"
	"mime/multipart"
	"net/http"
	"os"
	"path/filepath"
	"strings"

	. "github.com/sashabaranov/go-gpt3"
	"github.com/sashabaranov/go-gpt3/internal/test"

	"context"
	"testing"
)

// TestAudio Tests the transcription and translation endpoints of the API using the mocked server.
func TestAudio(t *testing.T) {
	server := test.NewTestServer()
	server.RegisterHandler("/v1/audio/transcriptions", handleAudioEndpoint)
	server.RegisterHandler("/v1/audio/translations", handleAudioEndpoint)
	// create the test server
	var err error
	ts := server.OpenAITestServer()
	ts.Start()
	defer ts.Close()

	config := DefaultConfig(test.GetTestToken())
	config.BaseURL = ts.URL + "/v1"
	client := NewClientWithConfig(config)

	testcases := []struct {
		name     string
		createFn func(context.Context, AudioRequest) (AudioResponse, error)
	}{
		{
			"transcribe",
			client.CreateTranscription,
		},
		{
			"translate",
			client.CreateTranslation,
		},
	}

	ctx := context.Background()

	dir, cleanup := createTestDirectory(t)
	defer cleanup()

	for _, tc := range testcases {
		t.Run(tc.name, func(t *testing.T) {
			path := filepath.Join(dir, "fake.mp3")
			createTestFile(t, path)

			req := AudioRequest{
				FilePath: path,
				Model:    "whisper-3",
			}
			_, err = tc.createFn(ctx, req)
			if err != nil {
				t.Fatalf("audio API error: %v", err)
			}
		})
	}
}

// createTestFile creates a fake file with "hello" as the content.
func createTestFile(t *testing.T, path string) {
	file, err := os.Create(path)
	if err != nil {
		t.Fatalf("failed to create file %v", err)
	}
	if _, err = file.WriteString("hello"); err != nil {
		t.Fatalf("failed to write to file %v", err)
	}
	file.Close()
}

// createTestDirectory creates a temporary folder which will be deleted when cleanup is called.
func createTestDirectory(t *testing.T) (path string, cleanup func()) {
	t.Helper()

	path, err := os.MkdirTemp(os.TempDir(), "")
	if err != nil {
		t.Fatal(err)
	}

	return path, func() { os.RemoveAll(path) }
}

// handleAudioEndpoint Handles the completion endpoint by the test server.
func handleAudioEndpoint(w http.ResponseWriter, r *http.Request) {
	var err error

	// audio endpoints only accept POST requests
	if r.Method != "POST" {
		http.Error(w, "method not allowed", http.StatusMethodNotAllowed)
	}

	mediaType, params, err := mime.ParseMediaType(r.Header.Get("Content-Type"))
	if err != nil {
		http.Error(w, "failed to parse media type", http.StatusBadRequest)
		return
	}

	if !strings.HasPrefix(mediaType, "multipart") {
		http.Error(w, "request is not multipart", http.StatusBadRequest)
	}

	boundary, ok := params["boundary"]
	if !ok {
		http.Error(w, "no boundary in params", http.StatusBadRequest)
		return
	}

	fileData := &bytes.Buffer{}
	mr := multipart.NewReader(r.Body, boundary)
	part, err := mr.NextPart()
	if err != nil && errors.Is(err, io.EOF) {
		http.Error(w, "error accessing file", http.StatusBadRequest)
		return
	}
	if _, err = io.Copy(fileData, part); err != nil {
		http.Error(w, "failed to copy file", http.StatusInternalServerError)
		return
	}

	if len(fileData.Bytes()) == 0 {
		w.WriteHeader(http.StatusInternalServerError)
		http.Error(w, "received empty file data", http.StatusBadRequest)
		return
	}

	if _, err = w.Write([]byte(`{"body": "hello"}`)); err != nil {
		http.Error(w, "failed to write body", http.StatusInternalServerError)
		return
	}
}