addressConverter.js

function AddressSectionMapper(sections) {
    this.sections = sections;
    this.sectionContainsAddress = function(section, address) {
    	if(section.off_beg <= address && address <= section.off_end) {
    		return true;
    	}
    	return false;
    };
    this.map = function(address) {
    	for (let section of sections) {
    		if(this.sectionContainsAddress(section, address)) {
    			return address - section.delta;
    		}
    	}
    	return null;
    };
    this.inverseMap = function(address) {
    	for (let section of sections) {
    		mappedAddress = address + section.delta
    		if(this.sectionContainsAddress(section, mappedAddress)) {
    			return mappedAddress;
    		}
    	}
    	return null;
    };
}

// Fortune Street Virtual to Fortune Street File
const fsvirt_to_fsfile = new AddressSectionMapper([
{off_beg: 0x80004000, off_end: 0x80006720, delta: 0x80003f00},
{off_beg: 0x80006720, off_end: 0x80006c80, delta: 0x7fbfda40},
{off_beg: 0x80006c80, off_end: 0x80007480, delta: 0x7fbfda40},
{off_beg: 0x80007480, off_end: 0x8040d940, delta: 0x80004c60},
{off_beg: 0x8040d940, off_end: 0x8040de80, delta: 0x80003f00},
{off_beg: 0x8040de80, off_end: 0x8040dea0, delta: 0x80003f00},
{off_beg: 0x8040dec0, off_end: 0x8044ea60, delta: 0x80003f20},
{off_beg: 0x8044ea60, off_end: 0x804ac680, delta: 0x80003f20},
{off_beg: 0x80814a80, off_end: 0x808171c0, delta: 0x8036c320},
{off_beg: 0x80818da0, off_end: 0x8081ede0, delta: 0x8036df00}
]);

// Boom Street Virtual to Boom Street File
const bsvirt_to_bsfile = new AddressSectionMapper([
{off_beg: 0x80004000, off_end: 0x80006720, delta: 0x80003f00},
{off_beg: 0x80006720, off_end: 0x80006c80, delta: 0x7fbfda00},
{off_beg: 0x80006c80, off_end: 0x80007480, delta: 0x7fbfda00},
{off_beg: 0x80007480, off_end: 0x8040d980, delta: 0x80004c60},
{off_beg: 0x8040d980, off_end: 0x8040dec0, delta: 0x80003f00},
{off_beg: 0x8040dec0, off_end: 0x8040dee0, delta: 0x80003f00},
{off_beg: 0x8040df00, off_end: 0x8044ec00, delta: 0x80003f20},
{off_beg: 0x8044ec00, off_end: 0x804ac820, delta: 0x80003f20},
{off_beg: 0x80814c80, off_end: 0x808173c0, delta: 0x8036c380},
{off_beg: 0x80818fa0, off_end: 0x8081efe0, delta: 0x8036df60}
]);

// Boom Street Virtual to Fortune Street Virtual
const bsvirt_to_fsvirt = new AddressSectionMapper([
{off_beg: 0x80000100, off_end: 0x8007a283, delta:   0x0},
{off_beg: 0x8007a2f4, off_end: 0x80268717, delta:  0x54},
{off_beg: 0x80268720, off_end: 0x8040d97b, delta:  0x50},
{off_beg: 0x8040d980, off_end: 0x8041027f, delta:  0x40},
{off_beg: 0x804105f0, off_end: 0x8044ebe7, delta: 0x188},
{off_beg: 0x8044ec00, off_end: 0x804ac804, delta: 0x1A0},
{off_beg: 0x804ac880, off_end: 0x8081f013, delta: 0x200}
]);