package scheduler_test

import (
	"testing"
	"time"

	"galaxy/gamemaster/internal/service/scheduler"

	"github.com/stretchr/testify/assert"
	"github.com/stretchr/testify/require"
)

func TestComputeNextHappyPathWithoutSkip(t *testing.T) {
	service := scheduler.New()
	after := time.Date(2026, time.April, 30, 12, 0, 0, 0, time.UTC)
	next, skipConsumed, err := service.ComputeNext("0 18 * * *", after, false)
	require.NoError(t, err)
	assert.False(t, skipConsumed)
	expected := time.Date(2026, time.April, 30, 18, 0, 0, 0, time.UTC)
	assert.Equal(t, expected, next)
	assert.Equal(t, time.UTC, next.Location())
}

func TestComputeNextConsumesSkip(t *testing.T) {
	service := scheduler.New()
	after := time.Date(2026, time.April, 30, 12, 0, 0, 0, time.UTC)
	next, skipConsumed, err := service.ComputeNext("0 18 * * *", after, true)
	require.NoError(t, err)
	assert.True(t, skipConsumed)
	expected := time.Date(2026, time.May, 1, 18, 0, 0, 0, time.UTC)
	assert.Equal(t, expected, next)
}

func TestComputeNextEveryQuarterHourSkip(t *testing.T) {
	service := scheduler.New()
	after := time.Date(2026, time.April, 30, 12, 0, 0, 0, time.UTC)
	first, _, err := service.ComputeNext("*/15 * * * *", after, false)
	require.NoError(t, err)
	skipped, _, err := service.ComputeNext("*/15 * * * *", after, true)
	require.NoError(t, err)
	assert.Equal(t, first.Add(15*time.Minute), skipped, "skip advances by exactly one cron step")
}

func TestComputeNextRejectsInvalidCron(t *testing.T) {
	service := scheduler.New()
	_, _, err := service.ComputeNext("not-a-cron", time.Now().UTC(), false)
	require.Error(t, err)
}

func TestComputeNextTrimsWhitespace(t *testing.T) {
	service := scheduler.New()
	after := time.Date(2026, time.April, 30, 12, 0, 0, 0, time.UTC)
	next, _, err := service.ComputeNext("  0 18 * * *  ", after, false)
	require.NoError(t, err)
	expected := time.Date(2026, time.April, 30, 18, 0, 0, 0, time.UTC)
	assert.Equal(t, expected, next)
}

func TestNilServiceRejected(t *testing.T) {
	var service *scheduler.Service
	_, _, err := service.ComputeNext("0 18 * * *", time.Now().UTC(), false)
	require.Error(t, err)
}