package metrics

import (
	"context"
	"encoding/json"
	"testing"
	"time"

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

func TestHourOf(t *testing.T) {
	got := HourOf(time.Date(2026, 8, 2, 21, 45, 0, 0, time.UTC))
	if got != "2026-08-02-21" {
		t.Fatalf("got %q, want 2026-08-02-21", got)
	}
}

func TestRawKeyDayKey(t *testing.T) {
	if got, want := RawKey("b", "2026-08-02-21"), "metrics/boxes/b/raw/2026-08-02-21.json"; got != want {
		t.Fatalf("RawKey got %q, want %q", got, want)
	}
	if got, want := DayKey("b", "2026-08-02"), "metrics/boxes/b/days/2026-08-02.json"; got != want {
		t.Fatalf("DayKey got %q, want %q", got, want)
	}
}

func sampleFloat(v float64) *float64 { return &v }

func TestWriteRawRoundTrip(t *testing.T) {
	store := release.NewDirStore(t.TempDir())
	ctx := context.Background()

	c := RawChunk{
		V:    1,
		Box:  "b",
		Hour: "2026-08-02-21",
		Samples: []Sample{
			{
				At:   time.Date(2026, 8, 2, 21, 0, 0, 0, time.UTC),
				Host: HostSample{CPUFrac: sampleFloat(0.5)},
				Units: map[string]UnitSample{
					"carlos-app@x.example.com.service": {CPUFrac: sampleFloat(0.1)},
				},
			},
		},
	}

	if err := WriteRaw(ctx, store, c); err != nil {
		t.Fatalf("WriteRaw: %v", err)
	}

	body, _, err := store.Get(ctx, RawKey(c.Box, c.Hour))
	if err != nil {
		t.Fatalf("Get: %v", err)
	}
	var got RawChunk
	if err := json.Unmarshal(body, &got); err != nil {
		t.Fatalf("Unmarshal: %v", err)
	}
	if got.V != c.V || got.Box != c.Box || got.Hour != c.Hour || len(got.Samples) != 1 {
		t.Fatalf("got %+v, want %+v", got, c)
	}
	if got.Samples[0].Host.CPUFrac == nil || *got.Samples[0].Host.CPUFrac != 0.5 {
		t.Fatalf("host cpu round-trip mismatch: %+v", got.Samples[0].Host)
	}
}

func TestWriteRawOverwriteSameHour(t *testing.T) {
	store := release.NewDirStore(t.TempDir())
	ctx := context.Background()

	first := RawChunk{V: 1, Box: "b", Hour: "2026-08-02-21", Samples: []Sample{
		{At: time.Date(2026, 8, 2, 21, 0, 0, 0, time.UTC), Host: HostSample{CPUFrac: sampleFloat(0.1)}},
	}}
	second := RawChunk{V: 1, Box: "b", Hour: "2026-08-02-21", Samples: []Sample{
		{At: time.Date(2026, 8, 2, 21, 5, 0, 0, time.UTC), Host: HostSample{CPUFrac: sampleFloat(0.2)}},
		{At: time.Date(2026, 8, 2, 21, 10, 0, 0, time.UTC), Host: HostSample{CPUFrac: sampleFloat(0.3)}},
	}}

	if err := WriteRaw(ctx, store, first); err != nil {
		t.Fatalf("WriteRaw first: %v", err)
	}
	if err := WriteRaw(ctx, store, second); err != nil {
		t.Fatalf("WriteRaw second: %v", err)
	}

	keys, err := store.List(ctx, "metrics/boxes/b/raw/")
	if err != nil {
		t.Fatalf("List: %v", err)
	}
	if len(keys) != 1 {
		t.Fatalf("got %d keys, want exactly one (overwrite, not a new object): %v", len(keys), keys)
	}

	body, _, err := store.Get(ctx, RawKey("b", "2026-08-02-21"))
	if err != nil {
		t.Fatalf("Get: %v", err)
	}
	var got RawChunk
	if err := json.Unmarshal(body, &got); err != nil {
		t.Fatalf("Unmarshal: %v", err)
	}
	if len(got.Samples) != 2 {
		t.Fatalf("got %d samples, want the latest write's 2 (latest content wins)", len(got.Samples))
	}
}

func TestStaleRawKeys(t *testing.T) {
	now := time.Date(2026, 8, 2, 22, 30, 0, 0, time.UTC)
	keys := []string{
		"metrics/boxes/b/raw/2026-07-31-10.json", // stale
		"metrics/boxes/b/raw/2026-08-02-21.json", // fresh
		"metrics/boxes/b/raw/garbage.json",       // unparsable — never returned
	}
	got := StaleRawKeys(keys, now, 48*time.Hour)
	if len(got) != 1 || got[0] != keys[0] {
		t.Fatalf("got %v, want only the stale key", got)
	}
}