package core

import (
	"strings"
	"testing"
	"time"
)

func TestGetNextUpdate(t *testing.T) {
	tests := []struct {
		lastUpdated time.Time
		spec        string
		expected    time.Time
		expectErr   bool
	}{
		{
			lastUpdated: time.Date(2020, 10, 22, 12, 0, 0, 0, time.UTC),
			spec:        "every 1h#1",
			expected:    time.Date(2020, 10, 22, 13, 0, 0, 0, time.UTC),
			expectErr:   false,
		},
		{
			lastUpdated: time.Date(2020, 10, 22, 12, 0, 5, 0, time.UTC),
			spec:        "every 1h#2",
			expected:    time.Date(2020, 10, 22, 13, 0, 0, 0, time.UTC),
			expectErr:   false,
		},
		{
			lastUpdated: time.Date(2020, 10, 22, 11, 0, 0, 0, time.UTC),
			spec:        "every 2h30m#1",
			expected:    time.Date(2020, 10, 22, 11, 30, 0, 0, time.UTC),
			expectErr:   false,
		},
		{
			lastUpdated: time.Date(2020, 10, 22, 11, 30, 0, 0, time.UTC),
			spec:        "every 2h30m#2",
			expected:    time.Date(2020, 10, 22, 14, 00, 0, 0, time.UTC),
			expectErr:   false,
		},
		{
			lastUpdated: time.Date(2020, 10, 22, 11, 30, 0, 0, time.UTC),
			spec:        "every 3",
			expected:    time.Time{},
			expectErr:   true,
		},
		{
			lastUpdated: time.Date(2020, 10, 22, 12, 0, 0, 0, time.UTC),
			spec:        "at 14:00#1",
			expected:    time.Date(2020, 10, 22, 14, 0, 0, 0, time.UTC),
			expectErr:   false,
		},
		{
			lastUpdated: time.Date(2020, 10, 22, 14, 0, 0, 0, time.UTC),
			spec:        "at 14:00#2",
			expected:    time.Date(2020, 10, 23, 14, 0, 0, 0, time.UTC),
			expectErr:   false,
		},
		{
			lastUpdated: time.Date(2020, 10, 22, 15, 0, 0, 0, time.UTC),
			spec:        "at 14:00#3",
			expected:    time.Date(2020, 10, 23, 14, 0, 0, 0, time.UTC),
			expectErr:   false,
		},
		{
			lastUpdated: time.Date(2020, 10, 22, 9, 0, 0, 0, time.UTC),
			spec:        "at 10:00,15:00#1",
			expected:    time.Date(2020, 10, 22, 10, 0, 0, 0, time.UTC),
			expectErr:   false,
		},
		{
			lastUpdated: time.Date(2020, 10, 22, 12, 0, 0, 0, time.UTC),
			spec:        "at 10:00,15:00#2",
			expected:    time.Date(2020, 10, 22, 15, 0, 0, 0, time.UTC),
			expectErr:   false,
		},
		{
			lastUpdated: time.Date(2020, 10, 22, 15, 0, 0, 0, time.UTC),
			spec:        "at 10:00,15:00#3",
			expected:    time.Date(2020, 10, 23, 10, 0, 0, 0, time.UTC),
			expectErr:   false,
		},
		{
			lastUpdated: time.Date(2020, 10, 22, 16, 0, 0, 0, time.UTC),
			spec:        "at 10:00,15:00#4",
			expected:    time.Date(2020, 10, 23, 10, 0, 0, 0, time.UTC),
			expectErr:   false,
		},
	}

	for _, test := range tests {
		t.Run(test.spec, func(t *testing.T) {
			spec := test.spec
			if comment := strings.Index(spec, "#"); comment > -1 {
				spec = spec[:comment]
			}
			nextUpdate, err := GetNextUpdate(test.lastUpdated, spec)
			if test.expectErr && err == nil {
				t.Error("test did not fail as expected")
			}
			if !test.expectErr && err != nil {
				t.Errorf("error: %v", err)
			}
			if !nextUpdate.Equal(test.expected) {
				t.Errorf("\nexpected: %v\n     got: %v", test.expected, nextUpdate)
			}
		})
	}

}