package orchestrator_test

import (
	"testing"

	"vetting/internal/model"
	"vetting/internal/orchestrator"
)

func TestNextForOverride(t *testing.T) {
	tests := []struct {
		name        string
		from        model.RunState
		failedStage string
		want        model.RunState
		wantErr     bool
	}{
		{"storage override", model.StateFailedHolding, "Storage", model.StateStorage, false},
		{"smart override", model.StateFailedHolding, "SMART", model.StateSMART, false},
		{"inventory override", model.StateFailedHolding, "Inventory", model.StateInventoryCheck, false},
		{"unknown stage", model.StateFailedHolding, "NotAStage", "", true},
		{"not holding", model.StateStorage, "Storage", "", true},
	}
	for _, tc := range tests {
		t.Run(tc.name, func(t *testing.T) {
			got, err := orchestrator.NextForOverride(tc.from, tc.failedStage)
			if tc.wantErr {
				if err == nil {
					t.Fatalf("expected error, got %q", got)
				}
				return
			}
			if err != nil {
				t.Fatalf("unexpected error: %v", err)
			}
			if got != tc.want {
				t.Fatalf("got %q, want %q", got, tc.want)
			}
		})
	}
}

// TestTriggerRebootCommanded exercises the new heartbeat-first trigger:
// Queued → WaitingReboot, and any other current state is an error.
func TestTriggerRebootCommanded(t *testing.T) {
	got, err := orchestrator.Next(model.StateQueued, orchestrator.TriggerRebootCommanded)
	if err != nil {
		t.Fatalf("Queued + RebootCommanded: %v", err)
	}
	if got != model.StateWaitingReboot {
		t.Fatalf("got %q, want %q", got, model.StateWaitingReboot)
	}
	for _, bad := range []model.RunState{
		model.StateRegistered, model.StateBooting, model.StateInventoryCheck, model.StateCompleted,
	} {
		if _, err := orchestrator.Next(bad, orchestrator.TriggerRebootCommanded); err == nil {
			t.Fatalf("RebootCommanded from %q: expected error", bad)
		}
	}
}

// TestTriggerAgentClaimedFromWaitingReboot: the agent's /claim must
// advance the run out of WaitingReboot (new happy path) AND out of
// legacy WaitingWoL, otherwise live boots wouldn't be recognised.
func TestTriggerAgentClaimedFromWaitingReboot(t *testing.T) {
	for _, from := range []model.RunState{model.StateWaitingReboot, model.StateWaitingWoL, model.StateBooting} {
		got, err := orchestrator.Next(from, orchestrator.TriggerAgentClaimed)
		if err != nil {
			t.Fatalf("AgentClaimed from %q: %v", from, err)
		}
		if got != model.StateInventoryCheck {
			t.Fatalf("AgentClaimed from %q = %q, want InventoryCheck", from, got)
		}
	}
}

// TestTriggerStageMismatch asserts the silent-skip guard: from every
// stage-execution state, a mismatch lands the run in FailedHolding, and
// from non-stage states (pre-stages, terminals) the trigger is rejected.
func TestTriggerStageMismatch(t *testing.T) {
	stageStates := []model.RunState{
		model.StateInventoryCheck,
		model.StateSpecValidate,
		model.StateSMART,
		model.StateCPUStress,
		model.StateStorage,
		model.StateNetwork,
		model.StateGPU,
		model.StatePSU,
		model.StateReporting,
	}
	for _, from := range stageStates {
		got, err := orchestrator.Next(from, orchestrator.TriggerStageMismatch)
		if err != nil {
			t.Fatalf("StageMismatch from %q: %v", from, err)
		}
		if got != model.StateFailedHolding {
			t.Fatalf("StageMismatch from %q = %q, want FailedHolding", from, got)
		}
	}
	for _, bad := range []model.RunState{
		model.StateRegistered, model.StateQueued, model.StateBooting,
		model.StateWaitingReboot, model.StateCompleted, model.StateFailedHolding,
	} {
		if _, err := orchestrator.Next(bad, orchestrator.TriggerStageMismatch); err == nil {
			t.Fatalf("StageMismatch from %q: expected error", bad)
		}
	}
}

// TestStageNameForState round-trips the stageStates map: every name in
// StateForStage must come back from StageNameForState, and non-stage
// run states return empty.
func TestStageNameForState(t *testing.T) {
	pairs := map[string]model.RunState{
		"Inventory":    model.StateInventoryCheck,
		"SpecValidate": model.StateSpecValidate,
		"SMART":        model.StateSMART,
		"CPUStress":    model.StateCPUStress,
		"Storage":      model.StateStorage,
		"Network":      model.StateNetwork,
		"GPU":          model.StateGPU,
		"PSU":          model.StatePSU,
		"Reporting":    model.StateReporting,
	}
	for name, state := range pairs {
		if got := orchestrator.StageNameForState(state); got != name {
			t.Errorf("StageNameForState(%q) = %q, want %q", state, got, name)
		}
	}
	for _, s := range []model.RunState{
		model.StateRegistered, model.StateQueued, model.StateBooting,
		model.StateWaitingReboot, model.StateCompleted, model.StateFailedHolding,
	} {
		if got := orchestrator.StageNameForState(s); got != "" {
			t.Errorf("StageNameForState(%q) = %q, want empty", s, got)
		}
	}
}

func TestNextStageWalk(t *testing.T) {
	// Walking StageCompleted from each stage should land on the next
	// one in the canonical order, and from Reporting onto Completed.
	chain := []model.RunState{
		model.StateInventoryCheck,
		model.StateSpecValidate,
		model.StateSMART,
		model.StateCPUStress,
		model.StateStorage,
		model.StateNetwork,
		model.StateGPU,
		model.StatePSU,
		model.StateReporting,
		model.StateCompleted,
	}
	for i := 0; i < len(chain)-1; i++ {
		got, err := orchestrator.Next(chain[i], orchestrator.TriggerStageCompleted)
		if err != nil {
			t.Fatalf("Next(%q): %v", chain[i], err)
		}
		if got != chain[i+1] {
			t.Fatalf("Next(%q) = %q, want %q", chain[i], got, chain[i+1])
		}
	}
}