package backup

import (
	"os"
	"testing"
)

// R-476 — a refreshed Tier-2 copy is dated by its DATA (the newest dump), not by a manifest that
// moves only when the app's definition changes; a PRESERVED package keeps the manifest date (R-403).
func TestR476_UnitRestoreDateNamesTheDataTimeWhenTheLegWasRefreshed(t *testing.T) {
	cov := Tier2Coverage{UnitPackageDate: "2026-09-12T02:15:29Z", UnitDataDate: "2026-09-13T00:30:00Z", CopyLastSuccess: "2026-09-13T01:30:00Z"}
	if d, preserved := cov.UnitRestoreDate(); d != "2026-09-13T00:30:00Z" || preserved {
		t.Errorf("refreshed leg: got %q preserved=%v, want the dump's time", d, preserved)
	}
	cov.UnitLegPreserved = true
	if d, preserved := cov.UnitRestoreDate(); d != "2026-09-12T02:15:29Z" || !preserved {
		t.Errorf("preserved leg: got %q preserved=%v, want the manifest's date", d, preserved)
	}
	older := Tier2Coverage{UnitPackageDate: "2026-09-13T02:00:00Z", UnitDataDate: "2026-09-12T00:30:00Z"}
	if d, _ := older.UnitRestoreDate(); d != "2026-09-13T02:00:00Z" {
		t.Errorf("data older than the manifest must not move the date backwards: %q", d)
	}
}

// R-476 — the coverage reader fills the data date from the mirrored unit's own artifacts.
func TestR476_CoverageReadsTheUnitDataDate(t *testing.T) {
	dest := t.TempDir()
	u := tier2UnitDir(dest)
	if err := os.MkdirAll(u, 0o755); err != nil {
		t.Fatal(err)
	}
	writeUnitManifest(t, u, []string{"app.sql"}, nil)
	cov := tier2CoverageAt(dest)
	if cov.UnitDataDate == "" {
		t.Fatal("UnitDataDate must be read from the unit")
	}
}