package netbox

import (
	"context"
	"errors"
	"net/http"
	"net/http/httptest"
	"strings"
	"sync/atomic"
	"testing"
)

// patchedDevice records whether the fake NetBox saw a PATCH on device 12.
var patchedDevice atomic.Bool

// fakeNetBox serves canned NetBox v4.x JSON for the endpoints bootapi calls.
// The payloads are trimmed but structurally faithful to real API responses.
func fakeNetBox(t *testing.T) *httptest.Server {
	t.Helper()
	mux := http.NewServeMux()

	// Interfaces filtered by MAC -> the interface (with nested device brief).
	mux.HandleFunc("/api/dcim/interfaces/", func(w http.ResponseWriter, r *http.Request) {
		if got := r.Header.Get("Authorization"); got != "Token testtoken" {
			http.Error(w, `{"detail":"auth"}`, http.StatusForbidden)
			return
		}
		q := r.URL.Query()
		switch {
		case q.Get("mac_address") == "aa:bb:cc:00:11:22":
			writeJSON(w, `{"count":1,"results":[
				{"id":40,"name":"eth0","mac_address":"AA:BB:CC:00:11:22",
				 "untagged_vlan":{"vid":100,"name":"prod"},
				 "device":{"id":12,"name":"web01","slug":""}}]}`)
		case q.Get("device_id") == "12":
			// Full interface list for the device (two NICs).
			writeJSON(w, `{"count":2,"results":[
				{"id":40,"name":"eth0","mac_address":"AA:BB:CC:00:11:22","untagged_vlan":{"vid":100,"name":"prod"}},
				{"id":41,"name":"eth1","mac_address":"AA:BB:CC:00:11:33"}]}`)
		default:
			writeJSON(w, `{"count":0,"results":[]}`)
		}
	})

	// Device detail (GET) + pxe_enabled write (PATCH).
	mux.HandleFunc("/api/dcim/devices/", func(w http.ResponseWriter, r *http.Request) {
		if r.Method == http.MethodPatch && strings.HasSuffix(r.URL.Path, "/12/") {
			patchedDevice.Store(true)
			writeJSON(w, `{"id":12,"name":"web01"}`)
			return
		}
		if strings.HasSuffix(r.URL.Path, "/12/") {
			writeJSON(w, `{
				"id":12,"name":"web01",
				"platform":{"id":3,"name":"AlmaLinux 9","slug":"almalinux9"},
				"role":{"id":2,"name":"K8s Worker","slug":"kubernetes-worker"},
				"site":{"slug":"syd1"},
				"primary_ip":{"address":"10.0.1.20/24"},
				"custom_fields":{"domain":"syd1.au.unkin.net","gateway":"10.0.1.254","nameservers":"10.0.0.1,10.0.0.2","provision_template":null,"pxe_enabled":true}}`)
			return
		}
		// name= query (HostByName)
		if r.URL.Query().Get("name") == "web01" {
			writeJSON(w, `{"count":1,"results":[{"id":12,"name":"web01"}]}`)
			return
		}
		writeJSON(w, `{"count":0,"results":[]}`)
	})

	// IP addresses for the device: eth0 has the primary, eth1 a second addr.
	mux.HandleFunc("/api/ipam/ip-addresses/", func(w http.ResponseWriter, _ *http.Request) {
		writeJSON(w, `{"count":2,"results":[
			{"address":"10.0.1.20/24","assigned_object_id":40,"custom_fields":{"gateway":null}},
			{"address":"10.9.9.5/24","assigned_object_id":41,"custom_fields":{"gateway":"10.9.9.1"}}]}`)
	})

	return httptest.NewServer(mux)
}

func writeJSON(w http.ResponseWriter, body string) {
	w.Header().Set("Content-Type", "application/json")
	_, _ = w.Write([]byte(body))
}

func newTestClient(t *testing.T, base string) *Client {
	t.Helper()
	return New(Options{BaseURL: base, Token: "testtoken"})
}

func TestHostByMAC(t *testing.T) {
	srv := fakeNetBox(t)
	defer srv.Close()
	c := newTestClient(t, srv.URL)

	h, err := c.HostByMAC(context.Background(), "AA-BB-CC-00-11-22")
	if err != nil {
		t.Fatalf("HostByMAC: %v", err)
	}
	if h.Hostname != "web01" {
		t.Errorf("hostname = %q, want web01", h.Hostname)
	}
	if h.FQDN != "web01.syd1.au.unkin.net" {
		t.Errorf("fqdn = %q", h.FQDN)
	}
	if h.Platform != "almalinux9" || h.OSFamily != "almalinux" || h.OSVersion != "9" {
		t.Errorf("platform=%q family=%q version=%q", h.Platform, h.OSFamily, h.OSVersion)
	}
	if h.Role != "kubernetes-worker" {
		t.Errorf("role = %q", h.Role)
	}
	if h.PrimaryIP != "10.0.1.20" {
		t.Errorf("primaryIP = %q", h.PrimaryIP)
	}
	if h.DeviceID != 12 {
		t.Errorf("deviceID = %d, want 12", h.DeviceID)
	}
	if h.PXEEnabled == nil || !*h.PXEEnabled || !h.ShouldPXEInstall() {
		t.Errorf("pxe_enabled = %v, want true", h.PXEEnabled)
	}
	if len(h.Nameservers) != 2 || h.Nameservers[0] != "10.0.0.1" {
		t.Errorf("nameservers = %v", h.Nameservers)
	}
	if len(h.Interfaces) != 2 {
		t.Fatalf("interfaces = %d, want 2", len(h.Interfaces))
	}
	// Primary interface (eth0, carrying the primary IP) must sort first.
	pi := h.PrimaryInterface()
	if pi == nil || pi.Name != "eth0" || !pi.Primary {
		t.Fatalf("primary interface = %+v", pi)
	}
	if pi.MAC != "aa:bb:cc:00:11:22" {
		t.Errorf("primary MAC = %q (want normalized lower-colon)", pi.MAC)
	}
	if pi.IP != "10.0.1.20" || pi.Netmask != "255.255.255.0" || pi.PrefixLen != 24 {
		t.Errorf("primary iface addr = %+v", pi)
	}
	// eth0 gateway comes from the device custom field (its IP had none).
	if pi.Gateway != "10.0.1.254" {
		t.Errorf("primary gateway = %q, want device CF 10.0.1.254", pi.Gateway)
	}
	if pi.VLAN != 100 {
		t.Errorf("primary vlan = %d", pi.VLAN)
	}
	// eth1's IP custom field gateway wins over the device default.
	for i := range h.Interfaces {
		if h.Interfaces[i].Name == "eth1" {
			if h.Interfaces[i].Gateway != "10.9.9.1" {
				t.Errorf("eth1 gateway = %q, want per-IP CF 10.9.9.1", h.Interfaces[i].Gateway)
			}
		}
	}
}

func TestHostByMACNotFound(t *testing.T) {
	srv := fakeNetBox(t)
	defer srv.Close()
	c := newTestClient(t, srv.URL)

	_, err := c.HostByMAC(context.Background(), "de:ad:be:ef:00:00")
	if !errors.Is(err, ErrNotFound) {
		t.Fatalf("err = %v, want ErrNotFound", err)
	}
}

func TestHostByName(t *testing.T) {
	srv := fakeNetBox(t)
	defer srv.Close()
	c := newTestClient(t, srv.URL)

	// FQDN input should be reduced to the short name for the NetBox query.
	h, err := c.HostByName(context.Background(), "web01.syd1.au.unkin.net")
	if err != nil {
		t.Fatalf("HostByName: %v", err)
	}
	if h.Hostname != "web01" || h.PrimaryIP != "10.0.1.20" {
		t.Errorf("host = %+v", h)
	}
}

func TestHostByNameNotFound(t *testing.T) {
	srv := fakeNetBox(t)
	defer srv.Close()
	c := newTestClient(t, srv.URL)
	if _, err := c.HostByName(context.Background(), "nope"); !errors.Is(err, ErrNotFound) {
		t.Fatalf("err = %v, want ErrNotFound", err)
	}
}

func TestAuthTokenRequired(t *testing.T) {
	srv := fakeNetBox(t)
	defer srv.Close()
	// Client with the wrong token -> NetBox 403 -> surfaced as an error.
	c := New(Options{BaseURL: srv.URL, Token: "wrong"})
	if _, err := c.HostByMAC(context.Background(), "aa:bb:cc:00:11:22"); err == nil {
		t.Fatal("expected an auth error, got nil")
	}
}

func TestSetPXEEnabled(t *testing.T) {
	srv := fakeNetBox(t)
	defer srv.Close()
	patchedDevice.Store(false)
	c := newTestClient(t, srv.URL)

	if err := c.SetPXEEnabled(context.Background(), 12, false); err != nil {
		t.Fatalf("SetPXEEnabled: %v", err)
	}
	if !patchedDevice.Load() {
		t.Error("expected a PATCH to device 12, got none")
	}
}

func TestCfBool(t *testing.T) {
	tr := true
	cases := []struct {
		cf   map[string]any
		want *bool
	}{
		{map[string]any{"pxe_enabled": true}, &tr},
		{map[string]any{"pxe_enabled": "false"}, boolp(false)},
		{map[string]any{"pxe_enabled": nil}, nil},
		{map[string]any{}, nil},
	}
	for _, c := range cases {
		got := cfBool(c.cf, "pxe_enabled")
		switch {
		case got == nil && c.want == nil:
		case got != nil && c.want != nil && *got == *c.want:
		default:
			t.Errorf("cfBool(%v) = %v, want %v", c.cf, got, c.want)
		}
	}
}

func boolp(b bool) *bool { return &b }

func TestNormalizeMAC(t *testing.T) {
	cases := map[string]string{
		"AA:BB:CC:00:11:22": "aa:bb:cc:00:11:22",
		"aa-bb-cc-00-11-22": "aa:bb:cc:00:11:22",
		"aabb.cc00.1122":    "aa:bb:cc:00:11:22",
		"AABBCC001122":      "aa:bb:cc:00:11:22",
	}
	for in, want := range cases {
		if got := normalizeMAC(in); got != want {
			t.Errorf("normalizeMAC(%q) = %q, want %q", in, got, want)
		}
	}
}

func TestSplitPlatform(t *testing.T) {
	cases := []struct{ in, fam, ver string }{
		{"almalinux9", "almalinux", "9"},
		{"fedora42", "fedora", "42"},
		{"rocky9.4", "rocky", "9"},
		{"debian", "debian", ""},
	}
	for _, c := range cases {
		f, v := splitPlatform(c.in)
		if f != c.fam || v != c.ver {
			t.Errorf("splitPlatform(%q) = (%q,%q), want (%q,%q)", c.in, f, v, c.fam, c.ver)
		}
	}
}

func TestNetmaskFor(t *testing.T) {
	cases := map[int]string{24: "255.255.255.0", 16: "255.255.0.0", 25: "255.255.255.128", 0: ""}
	for prefix, want := range cases {
		if got := netmaskFor(prefix); got != want {
			t.Errorf("netmaskFor(%d) = %q, want %q", prefix, got, want)
		}
	}
}