package scanner_test

import (
	"jinx/pkg/lang/scanner"
	"jinx/pkg/lang/scanner/token"
	"jinx/pkg/libs/source"
	"strings"
	"testing"

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

func TestBasic(t *testing.T) {
	src := `
	fn basic() {
		var x = 1
		var y = x + 1
		if x < y {
			say("x is less than y")
		} else {
			say("x is greater than or equal to y")
		}
		return true
	}`

	s := scanner.New(strings.NewReader(src))

	tokens, err := s.Scan()
	require.NoError(t, err)

	expected := []token.Token{
		token.Simple(token.EOL, source.NewLoc(0, 0)),

		token.Simple(token.KwFn, source.NewLoc(1, 1)),
		token.New(token.Ident, source.NewLoc(1, 4), "basic"),
		token.Simple(token.LParen, source.NewLoc(1, 9)),
		token.Simple(token.RParen, source.NewLoc(1, 10)),
		token.Simple(token.LBrace, source.NewLoc(1, 12)),
		token.Simple(token.EOL, source.NewLoc(1, 13)),

		token.Simple(token.KwVar, source.NewLoc(2, 2)),
		token.New(token.Ident, source.NewLoc(2, 6), "x"),
		token.Simple(token.Assign, source.NewLoc(2, 8)),
		token.New(token.Int, source.NewLoc(2, 10), uint64(1)),
		token.Simple(token.EOL, source.NewLoc(2, 11)),

		token.Simple(token.KwVar, source.NewLoc(3, 2)),
		token.New(token.Ident, source.NewLoc(3, 6), "y"),
		token.Simple(token.Assign, source.NewLoc(3, 8)),
		token.New(token.Ident, source.NewLoc(3, 10), "x"),
		token.Simple(token.Plus, source.NewLoc(3, 12)),
		token.New(token.Int, source.NewLoc(3, 14), uint64(1)),
		token.Simple(token.EOL, source.NewLoc(3, 15)),

		token.Simple(token.KwIf, source.NewLoc(4, 2)),
		token.New(token.Ident, source.NewLoc(4, 5), "x"),
		token.Simple(token.Lt, source.NewLoc(4, 7)),
		token.New(token.Ident, source.NewLoc(4, 9), "y"),
		token.Simple(token.LBrace, source.NewLoc(4, 11)),
		token.Simple(token.EOL, source.NewLoc(4, 12)),

		token.New(token.Ident, source.NewLoc(5, 3), "say"),
		token.Simple(token.LParen, source.NewLoc(5, 6)),
		token.New(token.String, source.NewLoc(5, 7), "x is less than y"),
		token.Simple(token.RParen, source.NewLoc(5, 25)),
		token.Simple(token.EOL, source.NewLoc(5, 26)),

		token.Simple(token.RBrace, source.NewLoc(6, 2)),
		token.Simple(token.KwElse, source.NewLoc(6, 4)),
		token.Simple(token.LBrace, source.NewLoc(6, 9)),
		token.Simple(token.EOL, source.NewLoc(6, 10)),

		token.New(token.Ident, source.NewLoc(7, 3), "say"),
		token.Simple(token.LParen, source.NewLoc(7, 6)),
		token.New(token.String, source.NewLoc(7, 7), "x is greater than or equal to y"),
		token.Simple(token.RParen, source.NewLoc(7, 40)),
		token.Simple(token.EOL, source.NewLoc(7, 41)),

		token.Simple(token.RBrace, source.NewLoc(8, 2)),
		token.Simple(token.EOL, source.NewLoc(8, 3)),

		token.Simple(token.KwReturn, source.NewLoc(9, 2)),
		token.Simple(token.KwTrue, source.NewLoc(9, 9)),
		token.Simple(token.EOL, source.NewLoc(9, 13)),

		token.Simple(token.RBrace, source.NewLoc(10, 1)),

		token.Simple(token.EOF, source.NewLoc(10, 2)),
	}

	require.Equal(t, expected, tokens)
}

func TestTightIdent(t *testing.T) {
	src := `say(message)`

	s := scanner.New(strings.NewReader(src))

	tokens, err := s.Scan()
	require.NoError(t, err)

	expected := []token.Token{
		token.New(token.Ident, source.NewLoc(0, 0), "say"),
		token.Simple(token.LParen, source.NewLoc(0, 3)),
		token.New(token.Ident, source.NewLoc(0, 4), "message"),
		token.Simple(token.RParen, source.NewLoc(0, 11)),
		token.Simple(token.EOF, source.NewLoc(0, 12)),
	}

	require.Equal(t, expected, tokens)
}

func TestTightNumber(t *testing.T) {
	src := `1+2+3`

	s := scanner.New(strings.NewReader(src))

	tokens, err := s.Scan()
	require.NoError(t, err)

	expected := []token.Token{
		token.New(token.Int, source.NewLoc(0, 0), uint64(1)),
		token.Simple(token.Plus, source.NewLoc(0, 1)),
		token.New(token.Int, source.NewLoc(0, 2), uint64(2)),
		token.Simple(token.Plus, source.NewLoc(0, 3)),
		token.New(token.Int, source.NewLoc(0, 4), uint64(3)),
		token.Simple(token.EOF, source.NewLoc(0, 5)),
	}

	require.Equal(t, expected, tokens)
}

func TestNewlineStacking(t *testing.T) {
	src := `
	x


	y
	`

	s := scanner.New(strings.NewReader(src))

	tokens, err := s.Scan()
	require.NoError(t, err)

	expected := []token.Token{
		token.Simple(token.EOL, source.NewLoc(0, 0)),
		token.New(token.Ident, source.NewLoc(1, 1), "x"),
		token.Simple(token.EOL, source.NewLoc(1, 2)),
		token.New(token.Ident, source.NewLoc(4, 1), "y"),
		token.Simple(token.EOL, source.NewLoc(4, 2)),
		token.Simple(token.EOF, source.NewLoc(5, 1)),
	}

	require.Equal(t, expected, tokens)
}

func TestEmojiInStrings(t *testing.T) {
	src := `
	say("🇺🇦" + "❤️!")
	`

	s := scanner.New(strings.NewReader(src))

	tokens, err := s.Scan()
	require.NoError(t, err)

	expected := []token.Token{
		token.Simple(token.EOL, source.NewLoc(0, 0)),
		token.New(token.Ident, source.NewLoc(1, 1), "say"),
		token.Simple(token.LParen, source.NewLoc(1, 4)),
		token.New(token.String, source.NewLoc(1, 5), "🇺🇦"),
		token.Simple(token.Plus, source.NewLoc(1, 10)),
		token.New(token.String, source.NewLoc(1, 12), "❤️!"),
		token.Simple(token.RParen, source.NewLoc(1, 17)),
		token.Simple(token.EOL, source.NewLoc(1, 18)),
		token.Simple(token.EOF, source.NewLoc(2, 1)),
	}

	require.Equal(t, expected, tokens)
}