ProDOS-Utilities/prodos/basic.go

package prodos

import (
	"fmt"
	"strings"
)

func ConvertBasicToText(basic []byte) string {
	var builder strings.Builder

	i := 0

	for {
		lo := basic[i]
		i++
		hi := basic[i]
		i++

		if lo == 0 && hi == 0 {
			builder.WriteString("\n")
			return builder.String()
		}

		line := int(basic[i]) + int(basic[i+1])*256
		i += 2

		fmt.Fprintf(&builder, "\n %d ", line)

		for {
			t := basic[i]
			if t == 0 {
				i++
				break
			}
			if t > 127 {
				builder.WriteString(getToken(t))
			} else {
				builder.WriteString(string(t))
			}
			i++
		}
	}
}

func getToken(token byte) string {
	tokens := map[byte]string{
		0x80: " END",
		0x81: " FOR ",
		0x82: " NEXT ",
		0x83: " DATA ",
		0x84: " INPUT ",
		0x85: " DEL ",
		0x86: " DIM ",
		0x87: " READ ",
		0x88: " GR",
		0x89: " TEXT ",
		0x8A: " PR# ",
		0x8B: " IN# ",
		0x8C: " CALL ",
		0x8D: " PLOT ",
		0x8E: " HLIN ",
		0x8F: " VLIN ",
		0x90: " HGR2",
		0x91: " HGR",
		0x92: " HCOLOR= ",
		0x93: " HPLOT ",
		0x94: " DRAW ",
		0x95: " XDRAW ",
		0x96: " HTAB ",
		0x97: " HOME ",
		0x98: " ROT= ",
		0x99: " SCALE= ",
		0x9A: " SHLOAD ",
		0x9B: " TRACE ",
		0x9C: " NOTRACE ",
		0x9D: " NORMAL ",
		0x9E: " INVERSE ",
		0x9F: " FLASH ",
		0xA0: " COLOR= ",
		0xA1: " POP ",
		0xA2: " VTAB ",
		0xA3: " HIMEM: ",
		0xA4: " LOMEM: ",
		0xA5: " ONERR",
		0xA6: " RESUME",
		0xA7: " RECALL",
		0xA8: " STORE ",
		0xA9: " SPEED= ",
		0xAA: " LET ",
		0xAB: " GOTO ",
		0xAC: " RUN ",
		0xAD: " IF ",
		0xAE: " RESTORE ",
		0xAF: " & ",
		0xB0: " GOSUB ",
		0xB1: " RETURN ",
		0xB2: " REM",
		0xB3: " STOP ",
		0xB4: " ON",
		0xB5: " WAIT ",
		0xB6: " LOAD ",
		0xB7: " SAVE ",
		0xB8: " DEF FN ",
		0xB9: " POKE ",
		0xBA: " PRINT ",
		0xBB: " CONT ",
		0xBC: " LIST ",
		0xBD: " CLEAR ",
		0xBE: " GET ",
		0xBF: " NEW ",
		0xC0: " TAB ",
		0xC1: " TO ",
		0xC2: " FN ",
		0xC3: " SPC(",
		0xC4: " THEN ",
		0xC5: " AT ",
		0xC6: " NOT ",
		0xC7: " STEP ",
		0xC8: " + ",
		0xC9: " - ",
		0xCA: " * ",
		0xCB: " / ",
		0xCC: " ; ",
		0xCD: " AND ",
		0xCE: " OR ",
		0xCF: " > ",
		0xD0: " = ",
		0xD1: " < ",
		0xD2: " SGN",
		0xD3: " INT",
		0xD4: " ABS",
		0xD5: " USR",
		0xD6: " FRE",
		0xD7: " SCRN(",
		0xD8: " PDL",
		0xD9: " POS",
		0xDA: " SQR",
		0xDB: " RND",
		0xDC: " LOG",
		0xDD: " EXP",
		0xDE: " COS",
		0xDF: " SIN",
		0xE0: " TAN",
		0xE1: " ATN",
		0xE2: " PEEK",
		0xE3: " LEN",
		0xE4: " STR$",
		0xE5: " VAL",
		0xE6: " ASC",
		0xE7: " CHR$",
		0xE8: " LEFT$",
		0xE9: " RIGHT$",
		0xEA: " MID$",
	}

	return tokens[token]
}