2025-07-27 22:16:36 -05:00

146 lines
3.2 KiB
Go

package parser
import (
"encoding/binary"
"eq2emu/internal/common"
"unsafe"
)
type ParseContext struct {
data []byte
offset int
version uint32
flags uint64
vars map[string]any
arrayStack []int
}
func NewContext(data []byte, version uint32, flags uint64) *ParseContext {
return &ParseContext{
data: data,
version: version,
flags: flags,
vars: make(map[string]any),
}
}
func (ctx *ParseContext) readUint8() uint8 {
val := ctx.data[ctx.offset]
ctx.offset++
return val
}
func (ctx *ParseContext) readUint16() uint16 {
val := binary.LittleEndian.Uint16(ctx.data[ctx.offset:])
ctx.offset += 2
return val
}
func (ctx *ParseContext) readUint32() uint32 {
val := binary.LittleEndian.Uint32(ctx.data[ctx.offset:])
ctx.offset += 4
return val
}
func (ctx *ParseContext) readOversizedUint8(threshold int) uint8 {
if ctx.data[ctx.offset] == byte(threshold) {
ctx.offset++
return ctx.readUint8()
}
return ctx.readUint8()
}
func (ctx *ParseContext) readOversizedUint16(threshold int) uint16 {
if ctx.data[ctx.offset] == byte(threshold) {
ctx.offset++
return ctx.readUint16()
}
return uint16(ctx.readUint8())
}
func (ctx *ParseContext) readString8() string {
length := ctx.readUint8()
str := string(ctx.data[ctx.offset : ctx.offset+int(length)])
ctx.offset += int(length)
return str
}
func (ctx *ParseContext) readString16() string {
length := ctx.readUint16()
str := string(ctx.data[ctx.offset : ctx.offset+int(length)])
ctx.offset += int(length)
return str
}
func (ctx *ParseContext) readEQ2String8() common.EQ2String8 {
size := ctx.readUint8()
data := string(ctx.data[ctx.offset : ctx.offset+int(size)])
ctx.offset += int(size)
return common.EQ2String8{
Size: size,
Data: data,
}
}
func (ctx *ParseContext) readEQ2String16() common.EQ2String16 {
size := ctx.readUint16()
data := string(ctx.data[ctx.offset : ctx.offset+int(size)])
ctx.offset += int(size)
return common.EQ2String16{
Size: size,
Data: data,
}
}
func (ctx *ParseContext) readEQ2String32() common.EQ2String32 {
size := ctx.readUint32()
data := string(ctx.data[ctx.offset : ctx.offset+int(size)])
ctx.offset += int(size)
return common.EQ2String32{
Size: size,
Data: data,
}
}
func (ctx *ParseContext) readEQ2Color() common.EQ2Color {
return common.EQ2Color{
Red: ctx.readUint8(),
Green: ctx.readUint8(),
Blue: ctx.readUint8(),
}
}
func (ctx *ParseContext) readEQ2Equipment() common.EQ2EquipmentItem {
return common.EQ2EquipmentItem{
Type: ctx.readUint16(),
Color: ctx.readEQ2Color(),
Highlight: ctx.readEQ2Color(),
}
}
func (ctx *ParseContext) readBytes(count int) []byte {
val := make([]byte, count)
copy(val, ctx.data[ctx.offset:ctx.offset+count])
ctx.offset += count
return val
}
func (ctx *ParseContext) readFloat32() float32 {
val := ctx.readUint32()
return *(*float32)(unsafe.Pointer(&val))
}
func (ctx *ParseContext) setVar(name string, value any) {
ctx.vars[name] = value
}
func (ctx *ParseContext) pushArrayIndex(index int) {
ctx.arrayStack = append(ctx.arrayStack, index)
}
func (ctx *ParseContext) popArrayIndex() {
if len(ctx.arrayStack) > 0 {
ctx.arrayStack = ctx.arrayStack[:len(ctx.arrayStack)-1]
}
}