package conf

import (
	"bytes"
	"errors"
	"reflect"
	"slices"
	"testing"
)

func TestRead(t *testing.T) {
	tc := []struct {
		name string
		in   []byte
		res  *Conf
		err  error
	}{
		{
			name: "empty",
			in:   []byte{},
			res: &Conf{
				values: nil, // no reads, so the slice has not been initialized
			},
			err: nil, // if the reader just returned io.EOF, which isn't an error for us
		},
		{
			name: "single key with spaces",
			in:   []byte("key = value"),
			res: &Conf{
				values: []*kv{
					{
						k: "key",
						v: Value("value"),
					},
				},
			},
			err: nil,
		},
		{
			name: "single key no spaces",
			in:   []byte("key=value"),
			res: &Conf{
				values: []*kv{
					{
						k: "key",
						v: Value("value"),
					},
				},
			},
			err: nil,
		},
		{
			name: "single key with newline",
			in:   []byte("key=value\n"),
			res: &Conf{
				values: []*kv{
					{
						k: "key",
						v: Value("value"),
					},
				},
			},
			err: nil,
		},
		{
			name: "single key with comment and newline",
			in:   []byte("key =value # this is a comment\n"),
			res: &Conf{
				values: []*kv{
					{
						k: "key",
						v: Value("value"),
					},
				},
			},
			err: nil,
		},
	}

	for _, c := range tc {
		t.Run(c.name, func(t *testing.T) {
			r := bytes.NewReader(c.in)

			conf, err := Read(r)
			if !errors.Is(err, c.err) {
				t.Fatalf("want error: %v have: %v", c.err, err)
			}

			if !reflect.DeepEqual(c.res, conf) {
				t.Fatalf("want: %+v, have: %+v", c.res, conf)
			}
		})
	}
}

func TestOpen(t *testing.T) {
	conf, err := Open("./testdata/test.conf")
	if err != nil {
		t.Fatal(err)
	}

	const (
		key   = "key"
		value = "value"
	)
	for _, n := range []string{"1", "2", "3", "4"} {
		v := conf.Get(key + n)
		if v.String() != value+n {
			t.Errorf("want: %s got: %s", value+n, v)
		}
	}
}

func TestKeys(t *testing.T) {
	c := Conf{
		values: []*kv{
			{
				k: "1",
				v: Value(""),
			},
			{
				k: "2",
				v: Value(""),
			},
			{
				k: "3",
				v: Value(""),
			},
		},
	}

	if !slices.Equal([]string{"1", "2", "3"}, c.Keys()) {
		t.Fatal("Keys method returns incorrect values")
	}
}