package dashboard

import (
	"strings"
	"testing"

	"ior/internal/flags"
	"ior/internal/statsengine"
)

func TestRenderProcessesIncludesHeaders(t *testing.T) {
	flags.SetPidFilter(-1)

	snap := statsengine.NewSnapshot(
		nil, nil, nil,
		nil, nil,
		[]statsengine.ProcessSnapshot{
			{PID: 200, Comm: "proc-b", Syscalls: 10, RatePerSec: 2.3, Bytes: 2048, AvgLatencyNs: 1500},
			{PID: 100, Comm: "proc-a", Syscalls: 20, RatePerSec: 4.6, Bytes: 4096, AvgLatencyNs: 2500},
		},
		statsengine.HistogramSnapshot{},
		statsengine.HistogramSnapshot{},
	)

	out := renderProcesses(&snap, 120, 30)
	for _, token := range []string{"PID", "Comm", "Syscalls", "Total Bytes", "Avg Latency"} {
		if !strings.Contains(out, token) {
			t.Fatalf("expected header token %q", token)
		}
	}
	if !strings.Contains(out, "100") || !strings.Contains(out, "proc-a") {
		t.Fatalf("expected process row in output")
	}
}

func TestRenderProcessesShowsSinglePIDNote(t *testing.T) {
	flags.SetPidFilter(77)
	t.Cleanup(func() { flags.SetPidFilter(-1) })

	snap := statsengine.NewSnapshot(
		nil, nil, nil,
		nil, nil,
		[]statsengine.ProcessSnapshot{
			{PID: 77, Comm: "proc", Syscalls: 1},
		},
		statsengine.HistogramSnapshot{},
		statsengine.HistogramSnapshot{},
	)

	out := renderProcesses(&snap, 100, 20)
	if !strings.Contains(out, "most useful with All PIDs") {
		t.Fatalf("expected single-pid guidance note")
	}
}

func TestTruncateText(t *testing.T) {
	got := truncateText("very-long-process-name", 10)
	if got != "very-lo..." {
		t.Fatalf("unexpected truncation result: %q", got)
	}
}