package mcp_test

import (
	"bytes"
	"encoding/json"
	"net/http"
	"net/http/httptest"
	"testing"

	"gitea.d-ma.be/mathias/gitea-mcp/internal/mcp"
	"gitea.d-ma.be/mathias/gitea-mcp/internal/registry"
	"github.com/stretchr/testify/assert"
	"github.com/stretchr/testify/require"
)

func newServer(t *testing.T) *mcp.Server {
	t.Helper()
	reg := registry.New()
	return mcp.NewServer(mcp.ServerOptions{
		Registry:        reg,
		OriginAllowlist: nil,
		Sessions:        mcp.NewSessionStore(),
	})
}

func postJSON(t *testing.T, srv http.Handler, body any, sessionID string) *httptest.ResponseRecorder {
	t.Helper()
	b, _ := json.Marshal(body)
	req := httptest.NewRequest(http.MethodPost, "/", bytes.NewBuffer(b))
	req.Header.Set("Content-Type", "application/json")
	req.Header.Set("Accept", "application/json, text/event-stream")
	if sessionID != "" {
		req.Header.Set("Mcp-Session-Id", sessionID)
	}
	rr := httptest.NewRecorder()
	srv.ServeHTTP(rr, req)
	return rr
}

func TestInitialize(t *testing.T) {
	srv := newServer(t)
	rr := postJSON(t, srv, map[string]any{
		"jsonrpc": "2.0",
		"id":      1,
		"method":  "initialize",
		"params":  map[string]any{"protocolVersion": "2025-06-18"},
	}, "")
	require.Equal(t, http.StatusOK, rr.Code)

	sid := rr.Header().Get("Mcp-Session-Id")
	assert.NotEmpty(t, sid)

	var resp map[string]any
	require.NoError(t, json.Unmarshal(rr.Body.Bytes(), &resp))
	result := resp["result"].(map[string]any)
	assert.Equal(t, "2025-06-18", result["protocolVersion"])
	si := result["serverInfo"].(map[string]any)
	assert.Equal(t, "gitea-mcp", si["name"])
}

func TestPostWithoutSessionRejected(t *testing.T) {
	srv := newServer(t)
	rr := postJSON(t, srv, map[string]any{
		"jsonrpc": "2.0",
		"id":      2,
		"method":  "tools/list",
	}, "")
	require.Equal(t, http.StatusBadRequest, rr.Code)
}

func TestToolsListAfterInitialize(t *testing.T) {
	srv := newServer(t)
	init := postJSON(t, srv, map[string]any{
		"jsonrpc": "2.0",
		"id":      1,
		"method":  "initialize",
		"params":  map[string]any{"protocolVersion": "2025-06-18"},
	}, "")
	sid := init.Header().Get("Mcp-Session-Id")

	rr := postJSON(t, srv, map[string]any{
		"jsonrpc": "2.0",
		"id":      2,
		"method":  "tools/list",
	}, sid)
	require.Equal(t, http.StatusOK, rr.Code)

	var resp map[string]any
	require.NoError(t, json.Unmarshal(rr.Body.Bytes(), &resp))
	result := resp["result"].(map[string]any)
	assert.Contains(t, result, "tools")
}