package webui

import (
	"context"
	"io"
	"net/http"
	"net/http/httptest"
	"net/url"
	"os"
	"path/filepath"
	"strings"
	"testing"

	"banger/internal/api"
	"banger/internal/model"
	"banger/internal/paths"
)

type fakeBackend struct {
	layout   paths.Layout
	config   model.DaemonConfig
	summary  api.DashboardSummary
	vms      []model.VMRecord
	images   []model.Image
	vm       model.VMRecord
	image    model.Image
	ports    api.VMPortsResult
	createOp api.VMCreateOperation
}

func (f fakeBackend) Config() model.DaemonConfig { return f.config }
func (f fakeBackend) Layout() paths.Layout       { return f.layout }
func (f fakeBackend) DashboardSummary(context.Context) (api.DashboardSummary, error) {
	return f.summary, nil
}
func (f fakeBackend) ListVMs(context.Context) ([]model.VMRecord, error)      { return f.vms, nil }
func (f fakeBackend) FindVM(context.Context, string) (model.VMRecord, error) { return f.vm, nil }
func (f fakeBackend) GetVMStats(context.Context, string) (model.VMRecord, model.VMStats, error) {
	return f.vm, f.vm.Stats, nil
}
func (f fakeBackend) BeginVMCreate(context.Context, api.VMCreateParams) (api.VMCreateOperation, error) {
	return f.createOp, nil
}
func (f fakeBackend) VMCreateStatus(context.Context, string) (api.VMCreateOperation, error) {
	return f.createOp, nil
}
func (f fakeBackend) StartVM(context.Context, string) (model.VMRecord, error)   { return f.vm, nil }
func (f fakeBackend) StopVM(context.Context, string) (model.VMRecord, error)    { return f.vm, nil }
func (f fakeBackend) RestartVM(context.Context, string) (model.VMRecord, error) { return f.vm, nil }
func (f fakeBackend) DeleteVM(context.Context, string) (model.VMRecord, error)  { return f.vm, nil }
func (f fakeBackend) SetVM(context.Context, api.VMSetParams) (model.VMRecord, error) {
	return f.vm, nil
}
func (f fakeBackend) PortsVM(context.Context, string) (api.VMPortsResult, error) { return f.ports, nil }
func (f fakeBackend) ListImages(context.Context) ([]model.Image, error)          { return f.images, nil }
func (f fakeBackend) FindImage(context.Context, string) (model.Image, error)     { return f.image, nil }
func (f fakeBackend) RegisterImage(context.Context, api.ImageRegisterParams) (model.Image, error) {
	return f.image, nil
}
func (f fakeBackend) PromoteImage(context.Context, string) (model.Image, error) { return f.image, nil }
func (f fakeBackend) DeleteImage(context.Context, string) (model.Image, error)  { return f.image, nil }

func TestDashboardPageRendersSummaryAndTables(t *testing.T) {
	backend := fakeBackend{
		layout: paths.Layout{StateDir: t.TempDir()},
		config: model.DaemonConfig{SSHKeyPath: "/tmp/id"},
		summary: api.DashboardSummary{
			Host: api.HostSummary{CPUCount: 8, TotalMemoryBytes: 16 << 30, StateFilesystemFreeBytes: 9 << 30, StateFilesystemTotalBytes: 20 << 30},
			Sudo: api.SudoStatus{Available: true, Command: "sudo -v"},
			Banger: api.BangerSummary{
				VMCount: 1, RunningVMCount: 1, ImageCount: 1, ManagedImageCount: 1, ConfiguredVCPUCount: 2,
				ConfiguredMemoryBytes: 1 << 30,
				ConfiguredDiskBytes:   8 << 30,
				UsedWorkDiskBytes:     3 << 30,
			},
		},
		vms:    []model.VMRecord{{ID: "vm-1", Name: "smth", State: model.VMStateRunning, CreatedAt: model.Now(), Runtime: model.VMRuntime{GuestIP: "172.16.0.2"}, Spec: model.VMSpec{VCPUCount: 2, MemoryMiB: 1024, WorkDiskSizeBytes: 8 << 30}}},
		images: []model.Image{{ID: "img-1", Name: "void", Managed: true, RootfsPath: "/tmp/rootfs.ext4", CreatedAt: model.Now()}},
	}

	req := httptest.NewRequest(http.MethodGet, "/", nil)
	rec := httptest.NewRecorder()
	NewHandler(backend).ServeHTTP(rec, req)

	if rec.Code != http.StatusOK {
		t.Fatalf("status = %d, want 200", rec.Code)
	}
	body := rec.Body.String()
	for _, want := range []string{"vCPU", "2 / 8", "1G / 16G", "8G / 20G", "9G free", "smth", "void", "Create VM"} {
		if !strings.Contains(body, want) {
			t.Fatalf("body missing %q\n%s", want, body)
		}
	}
	if len(rec.Result().Cookies()) == 0 {
		t.Fatal("expected csrf cookie to be set")
	}
}

func TestVMActionRejectsMissingCSRF(t *testing.T) {
	backend := fakeBackend{
		layout:  paths.Layout{StateDir: t.TempDir()},
		summary: api.DashboardSummary{Sudo: api.SudoStatus{Available: true}},
		vm:      model.VMRecord{ID: "vm-1", Name: "smth"},
	}
	req := httptest.NewRequest(http.MethodPost, "/vms/vm-1/start", strings.NewReader(""))
	req.Header.Set("Origin", "http://example.com")
	rec := httptest.NewRecorder()
	NewHandler(backend).ServeHTTP(rec, req)
	if rec.Code != http.StatusForbidden {
		t.Fatalf("status = %d, want 403", rec.Code)
	}
}

func TestFSAPIListsEntries(t *testing.T) {
	dir := t.TempDir()
	if err := os.Mkdir(filepath.Join(dir, "nested"), 0o755); err != nil {
		t.Fatalf("mkdir: %v", err)
	}
	if err := os.WriteFile(filepath.Join(dir, "rootfs.ext4"), []byte("data"), 0o644); err != nil {
		t.Fatalf("write: %v", err)
	}
	backend := fakeBackend{
		layout:  paths.Layout{StateDir: dir},
		summary: api.DashboardSummary{Sudo: api.SudoStatus{Available: true}},
	}

	req := httptest.NewRequest(http.MethodGet, "/api/fs?path="+url.QueryEscape(dir)+"&kind=file", nil)
	rec := httptest.NewRecorder()
	NewHandler(backend).ServeHTTP(rec, req)

	if rec.Code != http.StatusOK {
		t.Fatalf("status = %d, want 200", rec.Code)
	}
	data, err := io.ReadAll(rec.Body)
	if err != nil {
		t.Fatalf("ReadAll: %v", err)
	}
	body := string(data)
	for _, want := range []string{"rootfs.ext4", "nested"} {
		if !strings.Contains(body, want) {
			t.Fatalf("body missing %q\n%s", want, body)
		}
	}
}

func TestVMShowPageRendersRunningActions(t *testing.T) {
	backend := fakeBackend{
		layout:  paths.Layout{StateDir: t.TempDir()},
		config:  model.DaemonConfig{SSHKeyPath: "/tmp/id"},
		summary: api.DashboardSummary{Sudo: api.SudoStatus{Available: true, Command: "sudo -v"}},
		vm: model.VMRecord{
			ID:    "vm-1",
			Name:  "smth",
			State: model.VMStateRunning,
			Runtime: model.VMRuntime{
				GuestIP: "172.16.0.2",
			},
			Spec: model.VMSpec{
				VCPUCount:         2,
				MemoryMiB:         1024,
				WorkDiskSizeBytes: 8 << 30,
			},
			Stats: model.VMStats{
				CPUPercent:         12.5,
				RSSBytes:           64 << 20,
				SystemOverlayBytes: 2 << 20,
				WorkDiskBytes:      32 << 20,
			},
		},
		image: model.Image{ID: "img-1", Name: "void"},
		ports: api.VMPortsResult{
			Name: "smth",
			Ports: []api.VMPort{
				{Proto: "tcp", Port: 4096, Endpoint: "http://172.16.0.2:4096", Process: "devserver"},
			},
		},
	}

	req := httptest.NewRequest(http.MethodGet, "/vms/vm-1", nil)
	rec := httptest.NewRecorder()
	NewHandler(backend).ServeHTTP(rec, req)

	if rec.Code != http.StatusOK {
		t.Fatalf("status = %d, want 200", rec.Code)
	}
	body := rec.Body.String()
	for _, want := range []string{"Stop", "Restart", "href=\"http://172.16.0.2:4096\"", "data-confirm=\"Stop VM smth?\"", "data-confirm=\"Delete VM smth?\""} {
		if !strings.Contains(body, want) {
			t.Fatalf("body missing %q\n%s", want, body)
		}
	}
	for _, unwanted := range []string{"root@172.16.0.2"} {
		if strings.Contains(body, unwanted) {
			t.Fatalf("body unexpectedly contains %q\n%s", unwanted, body)
		}
	}
}

func TestVMListShowsImageNameAndLink(t *testing.T) {
	backend := fakeBackend{
		layout:  paths.Layout{StateDir: t.TempDir()},
		summary: api.DashboardSummary{Sudo: api.SudoStatus{Available: true}},
		vms: []model.VMRecord{
			{ID: "vm-1", Name: "smth", ImageID: "img-1", State: model.VMStateRunning, CreatedAt: model.Now(), Spec: model.VMSpec{VCPUCount: 2, MemoryMiB: 1024, WorkDiskSizeBytes: 8 << 30}},
		},
		images: []model.Image{
			{ID: "img-1", Name: "void"},
		},
	}

	req := httptest.NewRequest(http.MethodGet, "/vms", nil)
	rec := httptest.NewRecorder()
	NewHandler(backend).ServeHTTP(rec, req)

	if rec.Code != http.StatusOK {
		t.Fatalf("status = %d, want 200", rec.Code)
	}
	body := rec.Body.String()
	for _, want := range []string{">void</a>", "href=\"/images/img-1\""} {
		if !strings.Contains(body, want) {
			t.Fatalf("body missing %q\n%s", want, body)
		}
	}
}