package api

import (
	"context"
	"errors"
	"io"
	"log/slog"
	"net/http"
	"net/http/httptest"
	"strings"
	"testing"

	"github.com/moby/moby/api/types/container"
	"github.com/moby/moby/client"
)

type fakeContainerLister struct {
	containers []container.Summary
	err        error
	options    client.ContainerListOptions
}

func (f *fakeContainerLister) ContainerList(_ context.Context, options client.ContainerListOptions) (client.ContainerListResult, error) {
	f.options = options
	return client.ContainerListResult{Items: f.containers}, f.err
}

func TestListContainers(t *testing.T) {
	docker := &fakeContainerLister{containers: []container.Summary{{
		ID: "abc123", Names: []string{"/web"}, Image: "nginx:latest", State: "running",
	}}}
	request := httptest.NewRequest(http.MethodGet, "/api/v1/engines/1/containers", nil)
	response := httptest.NewRecorder()

	NewHandler(docker, testLogger()).ServeHTTP(response, request)

	if response.Code != http.StatusOK {
		t.Fatalf("status = %d, want %d", response.Code, http.StatusOK)
	}
	if !docker.options.All {
		t.Error("ContainerList All = false, want true")
	}
	if body := response.Body.String(); !strings.Contains(body, `"id":"abc123"`) {
		t.Errorf("response body does not contain container: %s", body)
	}
}

func TestListContainersRejectsUnknownEngine(t *testing.T) {
	response := httptest.NewRecorder()
	request := httptest.NewRequest(http.MethodGet, "/api/v1/engines/2/containers", nil)

	NewHandler(&fakeContainerLister{}, testLogger()).ServeHTTP(response, request)

	if response.Code != http.StatusNotFound {
		t.Fatalf("status = %d, want %d", response.Code, http.StatusNotFound)
	}
}

func TestListContainersHandlesDockerError(t *testing.T) {
	docker := &fakeContainerLister{err: errors.New("daemon unavailable")}
	response := httptest.NewRecorder()
	request := httptest.NewRequest(http.MethodGet, "/api/v1/engines/1/containers", nil)

	NewHandler(docker, testLogger()).ServeHTTP(response, request)

	if response.Code != http.StatusBadGateway {
		t.Fatalf("status = %d, want %d", response.Code, http.StatusBadGateway)
	}
	if body := response.Body.String(); !strings.Contains(body, `"code":"docker_unavailable"`) {
		t.Errorf("unexpected response body: %s", body)
	}
}

func testLogger() *slog.Logger {
	return slog.New(slog.NewTextHandler(io.Discard, nil))
}