// Copyright (c) 2024 Celestino Amoroso (celestino.amoroso@gmail.com).
// All rights reserved.

// scanner_test.go
package expr

import (
	"errors"
	"fmt"
	"strings"
	"testing"
)

func TestScanner(t *testing.T) {
	type inputType struct {
		source    string
		wantSym   Symbol
		wantValue any
		wantErr   error
	}

	inputs := []inputType{
		/*  1 */ {`123`, SymInteger, int64(123), nil},
		/*  2 */ {"=", SymEqual, nil, nil},
		/*  3 */ {`--`, SymDoubleMinus, nil, nil},
		/*  4 */ {`++`, SymDoublePlus, nil, nil},
		/*  5 */ {`**`, SymDoubleStar, nil, nil},
		/*  6 */ {`&&`, SymDoubleAmpersand, nil, nil},
		/*  7 */ {`||`, SymDoubleVertBar, nil, nil},
		/*  8 */ {`NOT`, SymKwNot, nil, nil},
		/*  9 */ {`AND`, SymKwAnd, nil, nil},
		/* 10 */ {`or`, SymKwOr, nil, nil},
		/* 11 */ {`+=`, SymPlusEqual, nil, nil},
		/* 12 */ {`-=`, SymMinusEqual, nil, nil},
		/* 13 */ {`|`, SymVertBar, nil, nil},
		/* 14 */ {`:`, SymColon, nil, nil},
		/* 15 */ {`;`, SymSemiColon, nil, nil},
		/* 16 */ {`.`, SymDot, nil, nil},
		/* 17 */ {`.5`, SymFloat, float64(0.5), nil},
		/* 18 */ {`\\`, SymBackSlash, nil, nil},
		/* 19 */ {"`", SymBackTick, nil, nil},
		/* 20 */ {"?", SymQuestion, nil, nil},
		/* 21 */ {"&", SymAmpersand, nil, nil},
		/* 22 */ {"@", SymAt, nil, nil},
		/* 23 */ {`#`, SymHash, nil, nil},
		/* 24 */ {`%`, SymPercent, nil, nil},
		/* 25 */ {`'`, SymQuote, nil, nil},
		/* 26 */ {`\"`, SymDoubleQuote, nil, nil},
		/* 27 */ {`_`, SymUndescore, nil, nil},
		/* 28 */ {`<>`, SymLessGreater, nil, nil},
		/* 29 */ {`[`, SymOpenSquare, nil, nil},
		/* 30 */ {`]`, SymClosedSquare, nil, nil},
		/* 31 */ {`{`, SymOpenBrace, nil, nil},
		/* 32 */ {`}`, SymClosedBrace, nil, nil},
		/* 33 */ {`(`, SymOpenRound, nil, nil},
		/* 34 */ {`)`, SymClosedRound, nil, nil},
		/* 35 */ {`1E+2`, SymFloat, float64(100), nil},
		/* 36 */ {`1E+x`, SymError, errors.New("expected integer exponent"), nil},
		/* 37 */ {`$`, SymDollar, nil, nil},
		/* 38 */ {`\`, SymError, errors.New("incomplete escape sequence"), nil},
		/* 39 */ {`"string"`, SymString, "string", nil},
		/* 39 */ {`identifier`, SymIdentifier, "identifier", nil},
	}

	for i, input := range inputs {

		if input.wantErr == nil {
			t.Log(fmt.Sprintf("[+]Test nr %2d -- %q", i+1, input.source))
		} else {
			t.Log(fmt.Sprintf("[-]Test nr %2d -- %q", i+1, input.source))
		}

		r := strings.NewReader(input.source)
		scanner := NewScanner(r, nil)

		if tk := scanner.Next(); tk == nil {
			t.Errorf("%d: %q -> got = (nil), want %v (value %v [%T)", i+1, input.source, input.wantSym, input.wantValue, input.wantValue)
		} else if tk.Sym != input.wantSym || tk.Value != input.wantValue {
			if tk.Sym == SymError && input.wantSym == tk.Sym {
				if tkErr, tkOk := tk.Value.(error); tkOk {
					if inputErr, inputOk := input.wantValue.(error); inputOk {
						if tkErr.Error() != inputErr.Error() {
							t.Errorf("%d: %q -> got-error = %v, want-error: %v", i+1,
								input.source, tk.Value, input.wantValue)
						}
					}
				}
			} else {
				t.Errorf("%d: %q -> got = %v (value=%v [%T), want %v (value=%v [%T)", i+1,
					input.source, tk.Sym, tk.Value, tk.Value, input.wantSym, input.wantValue, input.wantValue)
			}
		}
	}
}