package codexapp

import (
	"context"
	"encoding/json"
	"net"
	"net/http"
	"os"
	"path/filepath"
	"testing"
	"time"

	"github.com/gorilla/websocket"
)

func TestClientWebSocketUnixJSONRPC(t *testing.T) {
	ctx, cancel := context.WithTimeout(context.Background(), 5*time.Second)
	defer cancel()

	socketPath := filepath.Join(t.TempDir(), "codex.sock")
	serverDone := make(chan error, 1)
	ln, err := net.Listen("unix", socketPath)
	if err != nil {
		t.Fatal(err)
	}
	defer os.Remove(socketPath)

	upgrader := websocket.Upgrader{}
	server := &http.Server{Handler: http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		conn, err := upgrader.Upgrade(w, r, nil)
		if err != nil {
			serverDone <- err
			return
		}
		defer conn.Close()

		var initialize map[string]any
		if err := conn.ReadJSON(&initialize); err != nil {
			serverDone <- err
			return
		}
		if initialize["method"] != "initialize" {
			serverDone <- unexpectedMessage("initialize", initialize["method"])
			return
		}
		if err := conn.WriteJSON(map[string]any{"id": initialize["id"], "result": map[string]any{"userAgent": "test"}}); err != nil {
			serverDone <- err
			return
		}

		var initialized map[string]any
		if err := conn.ReadJSON(&initialized); err != nil {
			serverDone <- err
			return
		}
		if initialized["method"] != "initialized" {
			serverDone <- unexpectedMessage("initialized", initialized["method"])
			return
		}

		if err := conn.WriteJSON(map[string]any{
			"id":     99,
			"method": "item/commandExecution/requestApproval",
			"params": map[string]any{"threadId": "thr_1"},
		}); err != nil {
			serverDone <- err
			return
		}

		var start map[string]any
		if err := conn.ReadJSON(&start); err != nil {
			serverDone <- err
			return
		}
		if start["method"] != "thread/start" {
			serverDone <- unexpectedMessage("thread/start", start["method"])
			return
		}
		if err := conn.WriteJSON(map[string]any{
			"id": start["id"],
			"result": map[string]any{
				"thread": map[string]any{"id": "thr_1", "preview": "test"},
			},
		}); err != nil {
			serverDone <- err
			return
		}

		var setName map[string]any
		if err := conn.ReadJSON(&setName); err != nil {
			serverDone <- err
			return
		}
		if setName["method"] != "thread/name/set" {
			serverDone <- unexpectedMessage("thread/name/set", setName["method"])
			return
		}
		params := setName["params"].(map[string]any)
		if params["threadId"] != "thr_1" || params["name"] != "Short title" {
			payload, _ := json.Marshal(params)
			serverDone <- unexpectedMessage("thread/name/set params", string(payload))
			return
		}
		if err := conn.WriteJSON(map[string]any{"id": setName["id"], "result": map[string]any{}}); err != nil {
			serverDone <- err
			return
		}

		var response map[string]any
		if err := conn.ReadJSON(&response); err != nil {
			serverDone <- err
			return
		}
		if response["id"].(float64) != 99 || response["result"] != "accept" {
			payload, _ := json.Marshal(response)
			serverDone <- unexpectedMessage("approval response", string(payload))
			return
		}
		serverDone <- nil
	})}
	defer server.Close()
	go func() {
		_ = server.Serve(ln)
	}()

	client := New(socketPath, "test")
	if err := client.Connect(ctx); err != nil {
		t.Fatal(err)
	}
	defer client.Close()

	select {
	case event := <-client.Events():
		if !event.ServerRequest || event.ID == nil || *event.ID != 99 {
			t.Fatalf("unexpected event: %+v", event)
		}
	case <-ctx.Done():
		t.Fatal(ctx.Err())
	}

	thread, err := client.StartThread(ctx, "/tmp/project", "", "workspace-write")
	if err != nil {
		t.Fatal(err)
	}
	if thread.ID != "thr_1" {
		t.Fatalf("unexpected thread: %+v", thread)
	}
	if err := client.SetThreadName(ctx, "thr_1", "Short title"); err != nil {
		t.Fatal(err)
	}
	if err := client.RespondServerRequest(ctx, 99, "accept"); err != nil {
		t.Fatal(err)
	}

	select {
	case err := <-serverDone:
		if err != nil {
			t.Fatal(err)
		}
	case <-ctx.Done():
		t.Fatal(ctx.Err())
	}
}

type errUnexpected string

func (e errUnexpected) Error() string {
	return "unexpected " + string(e)
}

func unexpectedMessage(want string, got any) error {
	return errUnexpected("message: want " + want + ", got " + jsonString(got))
}

func jsonString(value any) string {
	data, _ := json.Marshal(value)
	return string(data)
}