package proxmox

import (
	"context"
	"errors"
	"strings"
	"sync"
	"testing"
	"time"

	"github.com/go-logr/logr/funcr"
	logf "sigs.k8s.io/controller-runtime/pkg/log"

	"gitea.home.hrajfrisbee.cz/kacerr/egress-proxies-operator/internal/provider"
)

// captureContext collects funcr output at V(2).
func captureContext() (context.Context, *[]string) {
	lines := &[]string{}
	var mu sync.Mutex
	log := funcr.New(func(prefix, args string) {
		mu.Lock()
		defer mu.Unlock()
		*lines = append(*lines, prefix+" "+args)
	}, funcr.Options{Verbosity: 2})
	return logf.IntoContext(context.Background(), log), lines
}

func testConfig() provider.ProxmoxConfig {
	return provider.ProxmoxConfig{
		URL:          "https://192.0.2.8:8006",
		TokenFile:    "/nonexistent/proxmox/token",
		Nodes:        []string{"pv1-1"},
		ISOStorage:   "proxy-seeds",
		Templates:    map[string]provider.ProxmoxTemplate{"debian-13": {VMID: 9001}},
		MachineTypes: map[string]provider.ProxmoxMachineType{"small": {Cores: 1, MemoryMiB: 1024}},
	}
}

func TestNew_doesNotDialAndWarnsOnMissingToken(t *testing.T) {
	t.Parallel()
	ctx, lines := captureContext()
	cfg := testConfig()
	start := time.Now()
	p, err := New(ctx, provider.ProviderConfig{Name: "proxmox-home", Type: "proxmox", Proxmox: &cfg})
	if err != nil || p == nil {
		t.Fatalf("New() = %v, %v; want a provider", p, err)
	}
	if elapsed := time.Since(start); elapsed > 100*time.Millisecond {
		t.Errorf("New() took %v, want under 100ms (it must not make a request)", elapsed)
	}
	var warnings int
	for _, l := range *lines {
		if strings.Contains(l, "WARNING:") && strings.Contains(l, "token file") {
			warnings++
		}
		if !strings.Contains(l, `"provider"="proxmox-home"`) {
			t.Errorf("log line lacks the provider value: %s", l)
		}
	}
	if warnings != 1 {
		t.Errorf("got %d token WARNING: lines, want 1:\n%s", warnings, strings.Join(*lines, "\n"))
	}
}

func TestNew_insecureSkipTLSVerifyWarns(t *testing.T) {
	t.Parallel()
	ctx, lines := captureContext()
	cfg := testConfig()
	cfg.InsecureSkipTLSVerify = true
	if _, err := New(ctx, provider.ProviderConfig{Name: "proxmox-home", Type: "proxmox", Proxmox: &cfg}); err != nil {
		t.Fatalf("New() error = %v, want nil", err)
	}
	for _, l := range *lines {
		if strings.Contains(l, "WARNING:") && strings.Contains(l, "not verified") {
			return
		}
	}
	t.Errorf("no insecureSkipTLSVerify warning in:\n%s", strings.Join(*lines, "\n"))
}

func TestNew_nilBlockDoesNotPanic(t *testing.T) {
	t.Parallel()
	ctx, _ := captureContext()
	p, err := New(ctx, provider.ProviderConfig{Name: "proxmox-empty", Type: "proxmox"})
	if err != nil {
		t.Fatalf("New() error = %v, want nil", err)
	}
	pp, ok := p.(*Provider)
	if !ok {
		t.Fatalf("New() = %T, want *Provider", p)
	}
	if pp.name != "proxmox-empty" || pp.cfg.VMIDRange == nil || pp.now == nil {
		t.Errorf("provider = %+v, want its name, defaults and a clock", pp)
	}
}

// TestNew_wiresObservedHTTPClient checks that production calls go through
// the logging decorator to the HTTP client, with /api2/json appended and
// the request timeout from the config.
func TestNew_wiresObservedHTTPClient(t *testing.T) {
	t.Parallel()
	ctx, _ := captureContext()
	cfg := testConfig()
	cfg.RequestTimeoutSeconds = 45
	p, err := New(ctx, provider.ProviderConfig{Name: "proxmox-home", Type: "proxmox", Proxmox: &cfg})
	if err != nil {
		t.Fatalf("New() error = %v", err)
	}
	o, ok := p.(*Provider).api.(*observed)
	if !ok {
		t.Fatalf("api = %T, want *observed", p.(*Provider).api)
	}
	h, ok := o.inner.(*httpAPI)
	if !ok {
		t.Fatalf("observed.inner = %T, want *httpAPI", o.inner)
	}
	if o.provider != "proxmox-home" || h.base.String() != "https://192.0.2.8:8006/api2/json" || h.timeout != 45*time.Second || h.tokenFile != cfg.TokenFile {
		t.Errorf("wiring = provider %q base %q timeout %v token file %q", o.provider, h.base, h.timeout, h.tokenFile)
	}
}

func TestWithDefaults_table(t *testing.T) {
	t.Parallel()
	off := false
	tests := []struct {
		name        string
		in          provider.ProxmoxConfig
		wantRange   provider.ProxmoxVMIDRange
		wantTimeout int
		wantAgent   bool
	}{
		{name: "empty fills every default", wantRange: provider.ProxmoxVMIDRange{Min: 100000, Max: 199999}, wantTimeout: 30, wantAgent: true},
		{
			name:        "explicit values kept",
			in:          provider.ProxmoxConfig{VMIDRange: &provider.ProxmoxVMIDRange{Min: 500, Max: 600}, RequestTimeoutSeconds: 45, InstallGuestAgent: &off},
			wantRange:   provider.ProxmoxVMIDRange{Min: 500, Max: 600},
			wantTimeout: 45,
			wantAgent:   false,
		},
	}
	for _, tc := range tests {
		t.Run(tc.name, func(t *testing.T) {
			t.Parallel()
			got := withDefaults(tc.in)
			if *got.VMIDRange != tc.wantRange || got.RequestTimeoutSeconds != tc.wantTimeout || *got.InstallGuestAgent != tc.wantAgent {
				t.Errorf("withDefaults() = range %+v timeout %d agent %v; want %+v %d %v",
					*got.VMIDRange, got.RequestTimeoutSeconds, *got.InstallGuestAgent, tc.wantRange, tc.wantTimeout, tc.wantAgent)
			}
		})
	}
}

func TestWithDefaults_doesNotShareWithCaller(t *testing.T) {
	t.Parallel()
	in := testConfig()
	in.VMIDRange = &provider.ProxmoxVMIDRange{Min: 500, Max: 600}
	got := withDefaults(in)
	got.Nodes[0] = "changed"
	got.VMIDRange.Min = 1
	got.Templates["debian-13"] = provider.ProxmoxTemplate{VMID: 1}
	got.MachineTypes["small"] = provider.ProxmoxMachineType{}
	if in.Nodes[0] != "pv1-1" || in.VMIDRange.Min != 500 || in.Templates["debian-13"].VMID != 9001 || in.MachineTypes["small"].Cores != 1 {
		t.Errorf("mutating the result changed the caller's config: %+v", in)
	}
}

func TestNode_table(t *testing.T) {
	t.Parallel()
	tests := []struct {
		name    string
		nodes   []string
		zone    string
		want    string
		wantErr string
	}{
		{name: "one node and empty zone selects it", nodes: []string{"pv1-1"}, zone: "", want: "pv1-1"},
		{name: "several nodes and empty zone is permanent", nodes: []string{"pv1-1", "pv1-2"}, zone: "", wantErr: "placement.zone is required"},
		{name: "known node", nodes: []string{"pv1-1", "pv1-2"}, zone: "pv1-2", want: "pv1-2"},
		{name: "unknown node is permanent", nodes: []string{"pv1-1"}, zone: "pv9", wantErr: `placement.zone "pv9" is not in proxmox.nodes`},
	}
	for _, tc := range tests {
		t.Run(tc.name, func(t *testing.T) {
			t.Parallel()
			cfg := testConfig()
			cfg.Nodes = tc.nodes
			got, err := newProvider("proxmox-home", cfg, nil).node(tc.zone)
			if tc.wantErr == "" {
				if err != nil || got != tc.want {
					t.Errorf("node(%q) = %q, %v; want %q, nil", tc.zone, got, err, tc.want)
				}
				return
			}
			if !errors.Is(err, provider.ErrPermanent) || !strings.Contains(err.Error(), tc.wantErr) {
				t.Errorf("node(%q) error = %v, want ErrPermanent containing %q", tc.zone, err, tc.wantErr)
			}
		})
	}
}

func TestWrapErr_carriesProviderNameOpAndID(t *testing.T) {
	t.Parallel()
	p := newProvider("proxmox-home", testConfig(), nil)
	err := p.wrapErr("get", "vms/150042/proxy-x", loadAPIError(t, "err_vm_missing"))
	var pe *provider.Error
	if !errors.As(err, &pe) {
		t.Fatalf("wrapErr() = %T, want *provider.Error", err)
	}
	if pe.Provider != "proxmox-home" || pe.Op != "get" || pe.ID != "vms/150042/proxy-x" || !errors.Is(err, provider.ErrNotFound) {
		t.Errorf("wrapErr() = %+v, want configured name, op, id and class NotFound", pe)
	}
	var ae *apiError
	if !errors.As(err, &ae) || ae.Status != 500 {
		t.Errorf("wrapErr() lost the underlying apiError: %v", err)
	}
}

func TestLockName_givesUpWithContextAsTransient(t *testing.T) {
	t.Parallel()
	p := newProvider("proxmox-home", testConfig(), nil)
	release, err := p.lockName(context.Background(), "proxy-abc")
	if err != nil {
		t.Fatalf("lockName error = %v", err)
	}
	defer release()
	other, err := p.lockName(context.Background(), "proxy-def")
	if err != nil {
		t.Fatalf("lockName on another name error = %v, want it free", err)
	}
	other()
	ctx, cancel := context.WithTimeout(context.Background(), 20*time.Millisecond)
	defer cancel()
	within(t, 5*time.Second, func() { _, err = p.lockName(ctx, "proxy-abc") })
	if !errors.Is(err, provider.ErrTransient) || !errors.Is(err, context.DeadlineExceeded) {
		t.Errorf("lockName on a held name error = %v, want ErrTransient wrapping DeadlineExceeded", err)
	}
}