package appconfig

import (
	"testing"

	"github.com/carlosframework/platform/internal/registry"
)

// fpExecRoute is the TCP-addr exec shape (issue #18): carlos proxies to it
// but neither spawns nor owns the process.
func fpExecRoute(host, env string) registry.Route {
	return registry.Route{Host: host, Kind: "instance", App: "titogo",
		Account: "bab", Status: "ready", Addr: "127.0.0.1:9001", Environment: env}
}

// fpUnitRoute is the unit-backed shape the ROOT pass delivers config for.
func fpUnitRoute(host, env string) registry.Route {
	return registry.Route{Host: host, Kind: "instance", App: "keymail",
		Account: "bae", Status: "ready", Addr: "127.0.0.1:9100",
		Backing: registry.BackingUnit, Environment: env}
}

func TestConfigRouteFingerprintsMoveOnRebinding(t *testing.T) {
	before := []registry.Route{fpExecRoute("connect.go.tito.io", "")}
	after := []registry.Route{fpExecRoute("connect.go.tito.io", "relay")}
	be, bu := ConfigRouteFingerprints(before)
	ae, au := ConfigRouteFingerprints(after)
	if be == ae {
		t.Fatal("binding an exec route to an environment must move the exec digest — this is the hour issue #196 cost")
	}
	if bu != au {
		t.Fatal("an exec route's rebinding must not move the UNIT digest — that would ask for a root config pass for nothing")
	}
}

func TestConfigRouteFingerprintsUnitHalfIsIndependent(t *testing.T) {
	before := []registry.Route{fpUnitRoute("keymail.dev", "")}
	after := []registry.Route{fpUnitRoute("keymail.dev", "staging")}
	be, bu := ConfigRouteFingerprints(before)
	ae, au := ConfigRouteFingerprints(after)
	if bu == au {
		t.Fatal("binding a unit-backed route to an environment must move the unit digest — the root pass resolves per environment too")
	}
	if be != ae {
		t.Fatal("a unit route's rebinding must not move the exec digest")
	}
}

func TestConfigRouteFingerprintsIgnoreOrderAndIrrelevantColumns(t *testing.T) {
	a := fpExecRoute("a.example", "")
	b := fpExecRoute("b.example", "relay")
	e1, _ := ConfigRouteFingerprints([]registry.Route{a, b})
	e2, _ := ConfigRouteFingerprints([]registry.Route{b, a})
	if e1 != e2 {
		t.Fatal("registry order must not move the digest — it is not stable across passes")
	}
	// A column that cannot change which bytes belong in a route's config
	// file must not move the digest, or every adopt would fire a pass.
	c := fpExecRoute("a.example", "")
	c.Version = "deadbeef"
	c.PrevVersion = "cafebabe"
	c.LastError = "whatever"
	c.Hibernate = true
	e3, _ := ConfigRouteFingerprints([]registry.Route{c, b})
	if e1 != e3 {
		t.Fatalf("an irrelevant column moved the digest (%s -> %s)", e1, e3)
	}
}

func TestConfigRouteFingerprintsMoveWhenARouteLeavesScope(t *testing.T) {
	both := []registry.Route{fpExecRoute("a.example", ""), fpExecRoute("b.example", "")}
	one := []registry.Route{fpExecRoute("a.example", "")}
	e1, _ := ConfigRouteFingerprints(both)
	e2, _ := ConfigRouteFingerprints(one)
	if e1 == e2 {
		t.Fatal("a route leaving the registry must move the digest — its file needs reaping")
	}
	// Leaving scope by STATUS, not by deletion, counts exactly the same:
	// the eligibility predicate is what set membership is drawn from.
	failed := []registry.Route{fpExecRoute("a.example", ""), fpExecRoute("b.example", "")}
	failed[1].Status = "failed"
	e3, _ := ConfigRouteFingerprints(failed)
	if e1 == e3 {
		t.Fatal("a route falling out of the eligibility predicate must move the digest")
	}
}

func TestConfigRouteFingerprintsIgnoreOutOfScopeRoutes(t *testing.T) {
	base := []registry.Route{fpExecRoute("a.example", "")}
	withOthers := append([]registry.Route{}, base...)
	withOthers = append(withOthers,
		// A static route: no config is delivered to it by either half.
		registry.Route{Host: "site.example", Kind: "static", App: "site", Account: "bab"},
		// A platform-minted row: excluded by execRouteBase and by
		// release.Adoptable alike.
		registry.Route{Host: "edge.example", Kind: "instance", App: "titogo", Account: "bab",
			Status: "ready", Addr: "127.0.0.1:9500", Platform: true},
	)
	e1, u1 := ConfigRouteFingerprints(base)
	e2, u2 := ConfigRouteFingerprints(withOthers)
	if e1 != e2 || u1 != u2 {
		t.Fatal("a route neither half can deliver config to must not move either digest")
	}
}

func TestConfigRouteFingerprintsEmptySetIsStable(t *testing.T) {
	e1, u1 := ConfigRouteFingerprints(nil)
	e2, u2 := ConfigRouteFingerprints([]registry.Route{})
	if e1 != e2 || u1 != u2 {
		t.Fatal("nil and empty must digest identically — a box with no routes must not look like it changed every tick")
	}
	if e1 == "" || u1 == "" {
		t.Fatal("the empty set must have a real digest, not the empty string: the fast loop tells 'never computed' from 'computed, and empty' by its own bool, not by this value")
	}
}