package vaultik //nolint:testpackage // exercises unexported parse helpers

import (
	"testing"
	"time"
)

func TestParseSnapshotName(t *testing.T) {
	t.Parallel()

	tests := []struct {
		name       string
		snapshotID string
		hostname   string
		want       string
	}{
		{
			name:       "standard format with name",
			snapshotID: "myhost_home_2026-01-12T14:41:15Z",
			hostname:   "myhost",
			want:       "home",
		},
		{
			name:       "standard format with different name",
			snapshotID: "server1_system_2026-02-15T09:30:00Z",
			hostname:   "server1",
			want:       "system",
		},
		{
			name:       "name with underscores",
			snapshotID: "myhost_my_special_backup_2026-03-01T00:00:00Z",
			hostname:   "myhost",
			want:       "my_special_backup",
		},
		{
			name:       "hostname with underscores",
			snapshotID: "my_host_docs_2026-03-01T00:00:00Z",
			hostname:   "my_host",
			want:       "docs",
		},
		{
			name:       "stored hostname with domain",
			snapshotID: "my_host_mail_2026-03-01T00:00:00Z",
			hostname:   "my_host.example.com",
			want:       "mail",
		},
		{
			name:       "no name",
			snapshotID: "my_host_2026-03-01T00:00:00Z",
			hostname:   "my_host",
			want:       "",
		},
	}

	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			t.Parallel()

			got := parseSnapshotName(tt.snapshotID, tt.hostname)
			if got != tt.want {
				t.Errorf("parseSnapshotName(%q, %q) = %q, want %q",
					tt.snapshotID, tt.hostname, got, tt.want)
			}
		})
	}
}

func TestParseDuration(t *testing.T) {
	t.Parallel()

	tests := []struct {
		input string
		want  time.Duration
		err   bool
	}{
		// Go units, including the m-is-minutes / mo-is-months distinction
		// that this parser exists to keep straight.
		{"10ns", 10 * time.Nanosecond, false},
		{"10us", 10 * time.Microsecond, false},
		{"500ms", 500 * time.Millisecond, false},
		{"30s", 30 * time.Second, false},
		{"6m", 6 * time.Minute, false},
		{"1h", time.Hour, false},
		{"1.5h", 90 * time.Minute, false},
		// Extended calendar units.
		{"30d", 30 * 24 * time.Hour, false},
		{"3days", 3 * 24 * time.Hour, false},
		{"4w", 4 * 7 * 24 * time.Hour, false},
		{"2weeks", 2 * 7 * 24 * time.Hour, false},
		{"6mo", 180 * 24 * time.Hour, false},
		{"1month", 30 * 24 * time.Hour, false},
		{"1y", 365 * 24 * time.Hour, false},
		{"2years", 2 * 365 * 24 * time.Hour, false},
		// Combined units.
		{"2w3d", 2*7*24*time.Hour + 3*24*time.Hour, false},
		{"1y6mo", 365*24*time.Hour + 180*24*time.Hour, false},
		// Rejected inputs.
		{"6", 0, true},   // bare number, no unit
		{"0", 0, true},   // bare number; time.ParseDuration accepts it
		{"+0", 0, true},  // bare number; time.ParseDuration accepts it
		{"5x", 0, true},  // unknown unit
		{"-5d", 0, true}, // negative, extended unit
		{"-5h", 0, true}, // negative, Go unit
		{"", 0, true},    // empty
		{"garbage", 0, true},
		// Characters outside the number-and-unit parts must not be
		// skipped: 1.0y read as 0y would select every snapshot.
		{"1.0y", 0, true},
		{"2.1w", 0, true},
		{"1,5y", 0, true},
		{"30 days", 0, true},
		{"30 days ago", 0, true},
		{"x7d", 0, true},
		// The largest time.Duration is about 292 years. A larger value
		// must be rejected, not wrapped to a negative one, which would
		// put the cutoff in the future and select every snapshot.
		{"292y", 292 * 365 * 24 * time.Hour, false},
		{"293y", 0, true},
		{"3559mo", 0, true},
		{"15251w", 0, true},
		{"106752d", 0, true},
		{"2562048h", 0, true},
		{"200y200y", 0, true},
		{"292y6mo", 0, true},
	}

	for _, tt := range tests {
		t.Run(tt.input, func(t *testing.T) {
			t.Parallel()

			got, err := parseDuration(tt.input)
			if tt.err {
				if err == nil {
					t.Fatalf("expected error for %q, got %v", tt.input, got)
				}

				return
			}

			if err != nil {
				t.Fatalf("unexpected error for %q: %v", tt.input, err)
			}

			if got != tt.want {
				t.Errorf("parseDuration(%q) = %v, want %v", tt.input, got, tt.want)
			}
		})
	}
}

func TestParseSnapshotTimestamp(t *testing.T) {
	t.Parallel()

	tests := []struct {
		name       string
		snapshotID string
		wantErr    bool
	}{
		{
			name:       "valid with name",
			snapshotID: "myhost_home_2026-01-12T14:41:15Z",
			wantErr:    false,
		},
		{
			name:       "valid without name",
			snapshotID: "myhost_2026-01-12T14:41:15Z",
			wantErr:    false,
		},
		{
			name:       "invalid - single part",
			snapshotID: "nounderscore",
			wantErr:    true,
		},
		{
			name:       "invalid - bad timestamp",
			snapshotID: "myhost_home_notadate",
			wantErr:    true,
		},
	}

	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			t.Parallel()

			_, err := parseSnapshotTimestamp(tt.snapshotID)
			if (err != nil) != tt.wantErr {
				t.Errorf("parseSnapshotTimestamp(%q) error = %v, wantErr %v",
					tt.snapshotID, err, tt.wantErr)
			}
		})
	}
}