// Copyright © 2023 Roberto Hidalgo <event-gateway@un.rob.mx>
// SPDX-License-Identifier: Apache-2.0
package source_test

import (
	"bytes"
	"net/http/httptest"
	"syscall"
	"testing"
	"testing/fstest"
	"time"

	"git.rob.mx/nidito/event-gateway/internal/config"
	"git.rob.mx/nidito/event-gateway/internal/source"
	"git.rob.mx/nidito/event-gateway/internal/source/http"
	"github.com/julienschmidt/httprouter"
	"github.com/sirupsen/logrus"
)

func TestManagerLifecycle(t *testing.T) {
	logrus.SetLevel(logrus.DebugLevel)

	payload := bytes.NewBufferString(`{"test": "test"}`)
	headers := map[string]string{
		"content-type": "application/json",
	}

	router := httprouter.New()
	src := &http.Source{Router: router}
	manager := &source.Manager{}
	manager.AddSource(src)

	cfg, err := config.FromURN("file://config.json")
	if err != nil {
		t.Fatalf("could not initialize configuration loader: %s", err)
	}

	// config loads
	t.Run("config loads", func(t *testing.T) {
		config.FS = fstest.MapFS{
			"config.json": &fstest.MapFile{
				Data: []byte(`{
					"event-id": {
						"source": {
							"kind": "http",
							"path": "some-path"
						},
						"sink": {
							"kind": "debug"
						}
					}
				}`),
			},
		}

		if err := manager.Listen(cfg); err != nil {
			t.Fatalf("could not start listener: %s", err)
		}

		time.Sleep(10 * time.Millisecond)
		res := testEvent("/-/some-path", payload, headers, router)
		body := res.Body.String()
		if body != "processed" {
			t.Fatalf("unexpected response wanted ok, got: %s", body)
		}
	})

	t.Run("config updates and deletes", func(t *testing.T) {
		config.FS = &fstest.MapFS{
			"config.json": &fstest.MapFile{
				Data: []byte(`{}`),
			},
		}

		syscall.Kill(syscall.Getpid(), syscall.SIGHUP)
		time.Sleep(10 * time.Millisecond)

		res := testEvent("/-/some-path", payload, headers, router)

		body := res.Body.String()
		if body != "ignored" {
			t.Fatalf("unexpected response wanted ignored, got: %s", body)
		}
	})

	t.Run("config updates and re-adds", func(t *testing.T) {
		config.FS = &fstest.MapFS{
			"config.json": &fstest.MapFile{
				Data: []byte(`{
					"event-id": {
						"source": {
							"kind": "http",
							"path": "some-path"
						},
						"sink": {
							"kind": "debug"
						}
					}
				}`),
			},
		}

		syscall.Kill(syscall.Getpid(), syscall.SIGHUP)
		time.Sleep(10 * time.Millisecond)

		res := testEvent("/-/some-path", payload, headers, router)
		body := res.Body.String()
		if body != "processed" {
			t.Fatalf("unexpected response wanted processed, got: %s", body)
		}
	})

	t.Run("config replaces", func(t *testing.T) {
		config.FS = &fstest.MapFS{
			"config.json": &fstest.MapFile{
				Data: []byte(`{
						"replaced": {
							"source": {
								"kind": "http",
								"path": "some-other-path"
							},
							"sink": {
								"kind": "debug"
							}
						}
					}`),
			},
		}

		syscall.Kill(syscall.Getpid(), syscall.SIGHUP)
		time.Sleep(10 * time.Millisecond)

		res := testEvent("/-/some-other-path", payload, headers, router)
		body := res.Body.String()
		if body != "processed" {
			t.Fatalf("unexpected response wanted processed, got: %s", body)
		}
	})

	t.Run("config updates listener with changes", func(t *testing.T) {
		config.FS = &fstest.MapFS{
			"config.json": &fstest.MapFile{
				Data: []byte(`{
						"replaced": {
							"source": {
								"kind": "http",
								"path": "some-path"
							},
							"sink": {
								"kind": "debug"
							}
						}
					}`),
			},
		}

		syscall.Kill(syscall.Getpid(), syscall.SIGHUP)
		time.Sleep(10 * time.Millisecond)

		res := testEvent("/-/some-path", payload, headers, router)
		body := res.Body.String()
		if body != "processed" {
			t.Fatalf("unexpected response wanted processed, got: %s", body)
		}
	})

	t.Run("config reloads without changes", func(t *testing.T) {
		syscall.Kill(syscall.Getpid(), syscall.SIGHUP)
		time.Sleep(10 * time.Millisecond)

		res := testEvent("/-/some-path", payload, headers, router)
		body := res.Body.String()
		if body != "processed" {
			t.Fatalf("unexpected response wanted processed, got: %s", body)
		}
	})
}

func testEvent(path string, payload *bytes.Buffer, headers map[string]string, router *httprouter.Router) *httptest.ResponseRecorder {
	res := httptest.NewRecorder()
	logrus.Debugf("Calling %s", path)
	req := httptest.NewRequest("POST", path, payload)
	for k, v := range headers {
		req.Header.Add(k, v)
	}
	router.ServeHTTP(res, req)
	return res
}