package reconcile

import (
	"context"
	"encoding/json"
	"strings"
	"testing"

	"gitea.dooplex.hu/admin/felhom-agent/internal/proxmox"
)

// R-834: a whole-guest restore BESIDE a live original must never come up as a second box on the same
// drives. The DR route keeps `onboot: 1`, binds the real drives and starts the guest, so it refuses
// when the original (or any guest binding the drives) is still on this host; on a replaced host it
// proceeds and keeps its binds. Red-proof: make liveOriginalBeside return "" and the refusals pass
// the restore through (the "refused" sub-tests fail).
func TestRunBringUp_DRRefusesBesideALiveOriginal(t *testing.T) {
	const target = 9299
	drivesBind := proxmox.GuestConfig{Extra: map[string]json.RawMessage{
		"mp8": json.RawMessage(`"/mnt/felhom-drives,mp=/mnt/felhom-drives"`),
	}}
	cases := []struct {
		name    string
		archive string
		lxc     []proxmox.Guest
		cfg     map[int]proxmox.GuestConfig
		refuse  string // substring of the refusal; "" = must proceed
	}{
		{"the source guest still exists", "local:backup/vzdump-lxc-9201-2026_10_04-04_34_55.tar.zst",
			[]proxmox.Guest{{VMID: 9201, Status: "running"}}, map[int]proxmox.GuestConfig{9201: scratchCfg()}, "source guest 9201"},
		{"another guest binds the drives (PBS archive)", "felhom-pbs:backup/ct/9201/2026-10-04T02:34:55Z",
			[]proxmox.Guest{{VMID: 9300, Status: "stopped"}}, map[int]proxmox.GuestConfig{9300: drivesBind}, "binds the household drives"},
		{"a guest whose config cannot be read", "local:backup/vzdump-lxc-9201-x.tar.zst",
			[]proxmox.Guest{{VMID: 9400, Status: "running"}}, map[int]proxmox.GuestConfig{}, "could not be read"},
		{"replaced host: only an unrelated scratch guest", "local:backup/vzdump-lxc-9201-x.tar.zst",
			[]proxmox.Guest{{VMID: 9202, Status: "running"}}, map[int]proxmox.GuestConfig{9202: scratchCfg()}, ""},
	}
	for _, c := range cases {
		t.Run(c.name, func(t *testing.T) {
			cfg := c.cfg
			cfg[target] = scratchCfg()
			api := &fakeAPI{lxc: c.lxc, cfg: cfg}
			e, fr, _, q := newDREngine(t, api)
			defer q.Close()
			res := e.RunBringUp(context.Background(), BringUpSpec{
				Mode: ModeDRGuestLoss, Archive: c.archive, VMID: target, RestoreStorage: "local-lvm", KeepMAC: true,
			})
			if c.refuse != "" {
				if res.Err == nil || !strings.Contains(res.Err.Error(), c.refuse) || !strings.Contains(res.Err.Error(), "R-834") {
					t.Fatalf("want a refusal naming %q, got %+v", c.refuse, res)
				}
				if len(api.restores) != 0 || len(api.starts) != 0 || len(fr.cmds) != 0 {
					t.Fatalf("a refused DR touched the host: restores=%d starts=%v cmds=%v", len(api.restores), api.starts, fr.cmds)
				}
				return
			}
			if res.Err != nil || !res.Pass {
				t.Fatalf("a DR on a replaced host must proceed, got %+v", res)
			}
			// … and there it keeps the REAL drives bind (the right binds on a replaced host).
			joined := strings.Join(fr.cmds, "\n")
			if !strings.Contains(joined, "-mp8 /mnt/felhom-drives,mp=/mnt/felhom-drives") {
				t.Fatalf("the DR guest lost its drives bind: %v", fr.cmds)
			}
		})
	}
}

// Provisioning restores the GOLDEN (no drives, onboot set by the back-half on purpose): a drives-
// binding guest on the host does not block it — the rule is DR's alone.
func TestRunBringUp_ProvisionNotBlockedByADrivesBind(t *testing.T) {
	api := &fakeAPI{
		lxc: []proxmox.Guest{{VMID: 9201, Status: "running"}},
		cfg: map[int]proxmox.GuestConfig{
			9201: {Extra: map[string]json.RawMessage{"mp8": json.RawMessage(`"/mnt/felhom-drives,mp=/mnt/felhom-drives"`)}},
			9203: scratchCfg(),
		},
	}
	e, _, q := newEngine(t, api, EmptyProvider{})
	defer q.Close()
	res := e.RunBringUp(context.Background(), BringUpSpec{Mode: ModeProvision, Archive: "local:vztmpl/felhom-golden.tar.zst", VMID: 9203, RestoreStorage: "local-lvm"})
	if res.Err != nil || !res.Pass {
		t.Fatalf("provision must proceed, got %+v", res)
	}
}

func TestArchiveSourceVMID(t *testing.T) {
	for in, want := range map[string]int{
		"local:backup/vzdump-lxc-9201-2026_10_04-04_34_55.tar.zst": 9201,
		"felhom-pbs:backup/ct/9201/2026-10-04T02:34:55Z":           9201,
		"tmp-dooplex-copy:backup/ct/9201/2026-10-03T19:00:00Z":     9201,
		"local:vztmpl/felhom-golden.tar.zst":                       0,
		"vol":                                                      0,
	} {
		if got := archiveSourceVMID(in); got != want {
			t.Errorf("archiveSourceVMID(%q) = %d, want %d", in, got, want)
		}
	}
}

// R-834, the restore-test route: its scratch guest sits BESIDE the live original by design, so it must
// carry no host-path bind — the archive's mp8 (the household's drives) and mp9 (the original's
// bootstrap) are replaced by throwaway volumes AT restore time. Measured live 2026-10-04 on demo-hp
// (`audits/backup-close-2026-10-04/partA/`): onboot 0 and no host bind on every poll. Red-proof:
// make drRestoreOverrides return the archive's own mp8 value and this fails.
func TestRestoreTest_NoHostPathBindBesideTheOriginal(t *testing.T) {
	api := &fakeAPI{
		cfg: map[int]proxmox.GuestConfig{990000: scratchCfg()},
		extractCfg: "hostname: demo-hp\nonboot: 1\nrootfs: local-lvm:vm-9201-disk-0,size=16G\n" +
			"mp0: local-lvm:vm-9201-disk-1,mp=/var/lib/felhom,backup=1,size=70G\n" +
			"mp8: /mnt/felhom-drives,mp=/mnt/felhom-drives\n" +
			"mp9: /var/lib/felhom-agent/guests/9201/bootstrap,mp=/etc/felhom-bootstrap,ro=1\n",
	}
	e, _, q := newEngine(t, api, EmptyProvider{})
	defer q.Close()
	_ = e.RunRestoreTest(context.Background(), RestoreTestSpec{
		Archive: "local:backup/vzdump-lxc-9201-x.tar.zst", RestoreStorage: "local-lvm",
		ScratchMin: 990000, ScratchMax: 990009, SourceTier: "local",
	})
	if len(api.restores) != 1 {
		t.Fatalf("want one restore, got %+v", api.restores)
	}
	r := api.restores[0]
	for _, slot := range []string{"mp8", "mp9"} {
		v, ok := r.MountOverrides[slot]
		if !ok || strings.HasPrefix(v, "/") {
			t.Fatalf("%s = %q (present=%v): the scratch beside the original must get a throwaway volume, never the host path", slot, v, ok)
		}
	}
	for slot, v := range r.MountOverrides {
		if strings.HasPrefix(v, "/") {
			t.Fatalf("%s carries a host path %q into the scratch guest", slot, v)
		}
	}
	if r.ConfigOverrides["onboot"] != "0" {
		t.Fatalf("onboot = %q, want 0", r.ConfigOverrides["onboot"])
	}
}