PCD2WC4/wc.go
2020-02-24 22:14:27 -08:00

89 lines
2.2 KiB
Go

package main
import (
"bufio"
"encoding/binary"
. "github.com/projectpokemon/PCD2WC4/util"
"io"
"log"
"os"
)
var blockPositions = [][]int{
{0, 0, 0, 0, 0, 0, 1, 1, 2, 3, 2, 3, 1, 1, 2, 3, 2, 3, 1, 1, 2, 3, 2, 3},
{1, 1, 2, 3, 2, 3, 0, 0, 0, 0, 0, 0, 2, 3, 1, 1, 3, 2, 2, 3, 1, 1, 3, 2},
{2, 3, 1, 1, 3, 2, 2, 3, 1, 1, 3, 2, 0, 0, 0, 0, 0, 0, 3, 2, 3, 2, 1, 1},
{3, 2, 3, 2, 1, 1, 3, 2, 3, 2, 1, 1, 3, 2, 3, 2, 1, 1, 0, 0, 0, 0, 0, 0},
}
func ConvertWondercard(f *os.File) []byte {
r := bufio.NewReader(f)
buf := make([]byte, 856)
_, err := io.ReadFull(r, buf)
if err != nil {
log.Printf("Error reading data for %s%s", f.Name(), LineBreak)
return nil
}
pkmBuf := buf[8:244]
pid := binary.LittleEndian.Uint32(pkmBuf[0:4])
seed := uint32(binary.LittleEndian.Uint16(pkmBuf[6:8]))
shiftValue := ((pid & 0x3E000) >> 0xD) % 24
decryptBuf := make([]byte, 228)
prng := NewPokemonRng(seed)
// Decrypt
for i := 0; i < 228; i += 2 {
if i == 128 { prng = NewPokemonRng(pid) }
v := binary.LittleEndian.Uint16(pkmBuf[i+8:i+10])
binary.LittleEndian.PutUint16(decryptBuf[i:i+2], v ^ prng.Next().H())
}
// Unshuffle the blocks
newBlocks := make([]byte, 228)
for block := 0; block < 4; block++ {
pos := 32 * blockPositions[block][shiftValue]
blockPos := block * 32
nextBlockPos := (block+1) * 32
copy(newBlocks[blockPos:nextBlockPos], decryptBuf[pos:32+pos])
}
// Copy party stuff
copy(newBlocks[128:228], decryptBuf[128:228])
wcBuf := make([]byte, 856)
copy(wcBuf[0:16], buf[0:16])
copy(wcBuf[16:244], newBlocks)
copy(wcBuf[244:], buf[244:])
return wcBuf
}
func SaveWondercard(saveData []byte, newPath string) {
// Save the data
newFile, err := os.Create(newPath)
if err != nil {
log.Printf("File: Error opening new file file %s%s", newPath, LineBreak)
return
}
writer := bufio.NewWriter(newFile)
if _, err := writer.Write(saveData); err != nil {
log.Printf("File: Error writing new file %v%s", err, LineBreak)
return
}
if err := writer.Flush(); err != nil {
log.Printf("File: Error flushing new file %v%s", err, LineBreak)
return
}
_ = newFile.Close()
log.Printf("Created %s%s", newPath, LineBreak)
}