package conf

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

func TestRead(t *testing.T) {
	tc := []struct {
		name string
		in   []byte
		want Map
		err  error
	}{
		{
			name: "empty",
			in:   []byte{},
			want: Map{},
			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"),
			want: Map{
				"key": Value("value"),
			},
			err: nil,
		},
		{
			name: "single key no spaces",
			in:   []byte("key=value"),
			want: Map{
				"key": Value("value"),
			},
			err: nil,
		},
		{
			name: "single key with newline",
			in:   []byte("key=value\n"),
			want: Map{
				"key": Value("value"),
			},
			err: nil,
		},
		{
			name: "single key with comment and newline",
			in:   []byte("key =value # something else \n"),
			want: Map{
				"key": Value("value # something else"),
			},
			err: nil,
		},
		{
			name: "incorrect k/v separator",
			in:   []byte("key ! value \n"),
			want: nil,
			err:  ErrFormat,
		},
		{
			name: "duplicate key",
			in:   []byte("key=value1\nkey=value2\n"),
			want: nil,
			err:  ErrDuplicateKey,
		},
	}

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

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

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

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 TestMainMethods(t *testing.T) {
	key := "key"
	value := "value"
	b := []byte(fmt.Sprintf("%s = %s", key, value))
	r := bytes.NewReader(b)

	m := make(Map)
	if err := m.Read(r); err != nil {
		t.Fatal(err)
	}

	if m.Get(key).String() != value {
		t.Error("Get fails for existing key")
	}

	if v, ok := m.Find("key"); !ok || v.String() != value {
		t.Error("Find fails for existing key")
	}

	if m.GetDefault(key, "none").String() != value {
		t.Error("GetDafault fails on existing value")
	}

	if m.GetDefault("unknown", value).String() != value {
		t.Error("GetDafault fails to supply default")
	}
}

func TestReadReadFile(t *testing.T) {
	m := make(Map)
	if err := m.ReadFile("./testdata/test.conf"); err != nil {
		t.Fatal(err)
	}

	f, err := os.Open("./testdata/test.conf")
	if err != nil {
		t.Fatal(err)
	}
	defer f.Close()

	m = make(Map)
	if err := m.Read(f); err != nil {
		t.Fatal(err)
	}
}

func TestKeys(t *testing.T) {
	m := Map{
		"1": Value(""),
		"2": Value(""),
		"3": Value(""),
	}

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