// Volition PEG/CPEG/GPEG Texture Format
// Used by: Saints Row 2/3/4, Red Faction: Guerrilla, Red Faction: Armageddon
// Magic: 0x564B4547 ("GEKV" LE/PC) or 0x47454B56 ("VKEG" BE/Xbox360)
// Versions: 10, 13
// Frame size: 48 bytes (0x30)
// CPEG = CPU texture header, GPEG = GPU texture data (paired files)

type volition_peg ui("Volition PEG Texture", root) byteorder LE
{
  criteria {
    // PC formats
    require _ext == "peg_pc" || _ext == "g_peg_pc" || _ext == "cvbm_pc" || _ext == "gvbm_pc" || _ext == "peg" ||
    // Xbox 360 formats
            _ext == "cpeg_xbox2" || _ext == "gpeg_xbox2" || _ext == "cvbm_xbox2" || _ext == "gvbm_xbox2" ||
    // PS3 formats
            _ext == "cpeg_ps3" || _ext == "gpeg_ps3" || _ext == "cvbm_ps3" || _ext == "gvbm_ps3";
    // Check magic in both endianness
    le_magic = u32at(0);
    require le_magic == 0x564B4547 || le_magic == 0x47454B56;
  }

  // Save original filename for display
  original_name = _name;

  // Detect platform from extension
  is_xbox = ends_with(_ext, "xbox2");
  is_ps3 = ends_with(_ext, "ps3");

  // Detect endianness from magic
  // GEKV (0x47454B56 in file) reads as 0x564B4547 in LE mode = PC
  // VKEG (0x564B4547 in file) reads as 0x47454B56 in LE mode = Xbox/PS3
  magic_check = u32at(0);
  if (magic_check == 0x47454B56) {
    // Big-endian (Xbox 360 / PS3)
    if (is_ps3) {
      set_name(original_name + " (PS3)");
    } else {
      set_name(original_name + " (Xbox 360)");
    }
    parse_here("volition_peg_be");
  } else {
    // Little-endian (PC)
    set_name(original_name + " (PC)");
    parse_here("volition_peg_impl");
  }
}

// Big-Endian wrapper for Xbox 360 / PS3
type volition_peg_be ui("PEG Texture") byteorder BE
{
  parse_here("volition_peg_impl");
}

// Shared implementation - inherits byteorder from caller
type volition_peg_impl ui("PEG Texture")
{
  magic = hex(read(4)) ui("Magic");
  u16 version ui("Version");
  u16 platform ui("Platform");

  if (version == 10) {
    parse_here("volition_peg_v10_body");
  } else if (version == 13) {
    parse_here("volition_peg_v13_body");
  } else {
    unknown_version = version ui("Unsupported Version");
    set_preview("peg_data.bin", read(size() - pos()));
    set_viewer("hex");
  }
}

// Helper function to get format name (shared by all versions)
// Includes both PC format codes (400-410) and Xbox 360 format codes (0x52-0x86)
type volition_peg_format_helper ui("Format Helper")
{
  f_format = ctx_get("_peg_format_code");

  // PC format codes (decimal 400-410)
  if (f_format == 400) { format_name = "DXT1"; }
  else if (f_format == 401) { format_name = "DXT3"; }
  else if (f_format == 402) { format_name = "DXT5"; }
  else if (f_format == 403) { format_name = "R5G6B5"; }
  else if (f_format == 404) { format_name = "A1R5G5B5"; }
  else if (f_format == 405) { format_name = "A4R4G4B4"; }
  else if (f_format == 406) { format_name = "R8G8B8"; }
  else if (f_format == 407) { format_name = "A8R8G8B8"; }
  else if (f_format == 408) { format_name = "V8U8"; }
  else if (f_format == 409) { format_name = "CxV8U8"; }
  else if (f_format == 410) { format_name = "A8"; }
  else if (f_format == 603) { format_name = "Unknown_603"; }
  // Xbox 360 format codes (hex 0x52-0x86)
  else if (f_format == 0x52) { format_name = "DXT1 (X360)"; }
  else if (f_format == 0x53) { format_name = "DXT3 (X360)"; }
  else if (f_format == 0x54) { format_name = "DXT5 (X360)"; }
  else if (f_format == 0x71) { format_name = "X8R8G8B8 (X360)"; }
  else if (f_format == 0x86) { format_name = "A8R8G8B8 (X360)"; }
  else { format_name = "Unknown_" + f_format; }

  ctx_set("_peg_format_name", format_name);
}

// PEG Version 10 body - Saints Row 2 (inherits byteorder)
type volition_peg_v10_body ui("PEG V10")
{
  set_name("PEG Texture (V10)");

  // Header continues after magic/version/platform (already read 8 bytes)
  u32 header_size ui("Header Size");
  u32 data_size ui("Data Size");
  u16 texture_count ui("Texture Count");
  u16 unknown0E ui("Unknown 0x0E");
  u16 frame_count ui("Frame Count");
  u8 unknown12 ui("Unknown 0x12");
  u8 unknown13 ui("Unknown 0x13");

  // Parse frames (48 bytes each)
  skip_tree("frames");
  frame_idx = 0;
  repeat(frame_count) {
    u32 f_data_offset;
    u16 f_width;
    u16 f_height;
    u32 f_format;
    u32 f_unknown0C;
    u16 f_frame_count;
    u16 f_flags;
    u32 f_name_offset;
    u32 f_unknown18;
    u32 f_size;
    u32 f_unknown20;
    u32 f_unknown24;
    u32 f_unknown28;
    u32 f_unknown2C;

    ctx_set("_peg_frame_idx", frame_idx);
    ctx_set("_peg_frame_offset", f_data_offset);
    ctx_set("_peg_frame_width", f_width);
    ctx_set("_peg_frame_height", f_height);
    ctx_set("_peg_frame_format", f_format);
    ctx_set("_peg_frame_size", f_size);
    ctx_set("_peg_frame_flags", f_flags);

    // Get format name using shared helper
    ctx_set("_peg_format_code", f_format);
    _dummy = bytesat(0, 1) |> parse volition_peg_format_helper;
    format_name = ctx_get("_peg_format_name");
    ctx_set("_peg_frame_format_name", format_name);

    dummy = bytesat(0, 1);
    frame_child = dummy |> parse volition_peg_frame_row;
    push("frames", frame_child);

    frame_idx = frame_idx + 1;
  }

  // Parse texture names (null-terminated strings)
  name_idx = 0;
  repeat(texture_count) {
    tex_name = cstring();
    ctx_set("_peg_tex_name_" + name_idx, tex_name);
    name_idx = name_idx + 1;
  }

  ui_table("frames", "frames", "Index,Width,Height,Format,Size,Flags");

  // Extract textures from paired GPEG if available
  has_gpeg = ctx_get("_peg_has_gpeg");
  if (has_gpeg == 1) {
    gpeg_data = ctx_get("_peg_gpeg_data");
    gpeg_len = len(gpeg_data);

    // Initialize texture index counter
    ctx_set("_peg_tex_idx", 0);

    // Re-parse frames to extract texture data
    seek(20); // Skip back to frame table (after 8-byte header + 12 bytes we read)
    tex_idx = 0;
    repeat(frame_count) {
      u32 tex_data_offset;
      u16 tex_width;
      u16 tex_height;
      u32 tex_format;
      skip(4); // unknown0C
      skip(4); // frame_count + flags
      skip(4); // name_offset
      skip(4); // unknown18
      u32 tex_size;
      skip(12); // remaining unknowns

      // Extract texture data from GPEG
      if (tex_data_offset + tex_size <= gpeg_len && tex_size > 0) {
        // Get texture name
        tex_name = ctx_get("_peg_tex_name_" + tex_idx);
        if (len(tex_name) == 0) {
          tex_name = "texture_" + tex_idx;
        }

        // Get format name
        ctx_set("_peg_format_code", tex_format);
        _dummy2 = bytesat(0, 1) |> parse volition_peg_format_helper;
        tex_format_name = ctx_get("_peg_format_name");

        // Store texture info in context for extraction
        ctx_set("_peg_extract_offset", tex_data_offset);
        ctx_set("_peg_extract_size", tex_size);
        ctx_set("_peg_extract_name", tex_name);
        ctx_set("_peg_extract_width", tex_width);
        ctx_set("_peg_extract_height", tex_height);
        ctx_set("_peg_extract_format", tex_format_name);

        // Parse GPEG data to extract texture - the extractor reads from gpeg_data stream
        tex_child = gpeg_data |> parse volition_peg_texture_extractor;
        push("extracted_textures", tex_child);
      }

      tex_idx = tex_idx + 1;
    }

    gpeg_paired = "Yes (" + gpeg_len + " bytes)" ui("GPEG Paired");
  } else {
    gpeg_paired = "No" ui("GPEG Paired");
  }

  total_frames = frame_count ui("Total Frames");
  total_textures = texture_count ui("Total Textures");
  file_size = size() ui("File Size");
}

// PEG Version 13 body - Red Faction: Armageddon (inherits byteorder)
type volition_peg_v13_body ui("PEG V13")
{
  set_name("PEG Texture (V13)");

  // Header continues after magic/version/platform (already read 8 bytes)
  u32 header_size ui("Header Size");
  u32 data_size ui("Data Size");
  u16 texture_count ui("Texture Count");
  u16 unknown0E ui("Unknown 0x0E");
  u16 frame_count ui("Frame Count");
  u16 unknown12 ui("Unknown 0x12");

  // Parse frames (48 bytes each - same as V10)
  skip_tree("frames");
  frame_idx = 0;
  repeat(frame_count) {
    u32 f_data_offset;
    u16 f_width;
    u16 f_height;
    u32 f_format;
    u32 f_unknown0C;
    u16 f_frame_count;
    u16 f_flags;
    u32 f_name_offset;
    u32 f_unknown18;
    u32 f_size;
    u32 f_unknown20;
    u32 f_unknown24;
    u32 f_unknown28;
    u32 f_unknown2C;

    ctx_set("_peg_frame_idx", frame_idx);
    ctx_set("_peg_frame_offset", f_data_offset);
    ctx_set("_peg_frame_width", f_width);
    ctx_set("_peg_frame_height", f_height);
    ctx_set("_peg_frame_format", f_format);
    ctx_set("_peg_frame_size", f_size);
    ctx_set("_peg_frame_flags", f_flags);

    // Get format name using shared helper
    ctx_set("_peg_format_code", f_format);
    _dummy = bytesat(0, 1) |> parse volition_peg_format_helper;
    format_name = ctx_get("_peg_format_name");
    ctx_set("_peg_frame_format_name", format_name);

    dummy = bytesat(0, 1);
    frame_child = dummy |> parse volition_peg_frame_row;
    push("frames", frame_child);

    frame_idx = frame_idx + 1;
  }

  // Parse texture names (null-terminated strings)
  name_idx = 0;
  repeat(texture_count) {
    tex_name = cstring();
    ctx_set("_peg_tex_name_" + name_idx, tex_name);
    name_idx = name_idx + 1;
  }

  ui_table("frames", "frames", "Index,Width,Height,Format,Size,Flags");

  // Extract textures from paired GPEG if available
  has_gpeg = ctx_get("_peg_has_gpeg");
  if (has_gpeg == 1) {
    gpeg_data = ctx_get("_peg_gpeg_data");
    gpeg_len = len(gpeg_data);

    // Initialize texture index counter
    ctx_set("_peg_tex_idx", 0);

    // Re-parse frames to extract texture data
    seek(20); // Skip back to frame table
    tex_idx = 0;
    repeat(frame_count) {
      u32 tex_data_offset;
      u16 tex_width;
      u16 tex_height;
      u32 tex_format;
      skip(4); // unknown0C
      skip(4); // frame_count + flags
      skip(4); // name_offset
      skip(4); // unknown18
      u32 tex_size;
      skip(12); // remaining unknowns

      if (tex_data_offset + tex_size <= gpeg_len && tex_size > 0) {
        tex_name = ctx_get("_peg_tex_name_" + tex_idx);
        if (len(tex_name) == 0) {
          tex_name = "texture_" + tex_idx;
        }

        ctx_set("_peg_format_code", tex_format);
        _dummy2 = bytesat(0, 1) |> parse volition_peg_format_helper;
        tex_format_name = ctx_get("_peg_format_name");

        ctx_set("_peg_extract_offset", tex_data_offset);
        ctx_set("_peg_extract_size", tex_size);
        ctx_set("_peg_extract_name", tex_name);
        ctx_set("_peg_extract_width", tex_width);
        ctx_set("_peg_extract_height", tex_height);
        ctx_set("_peg_extract_format", tex_format_name);

        tex_child = gpeg_data |> parse volition_peg_texture_extractor;
        push("extracted_textures", tex_child);
      }

      tex_idx = tex_idx + 1;
    }

    gpeg_paired = "Yes (" + gpeg_len + " bytes)" ui("GPEG Paired");
  } else {
    gpeg_paired = "No" ui("GPEG Paired");
  }

  total_frames = frame_count ui("Total Frames");
  total_textures = texture_count ui("Total Textures");
  file_size = size() ui("File Size");
}

// Frame row for table display (inherits byteorder, but only uses context)
type volition_peg_frame_row ui("Frame")
{
  set_hidden();
  Index = ctx_get("_peg_frame_idx");
  Width = ctx_get("_peg_frame_width");
  Height = ctx_get("_peg_frame_height");
  Format = ctx_get("_peg_frame_format_name");
  Size = ctx_get("_peg_frame_size");
  Flags = ctx_get("_peg_frame_flags");
  set_name(Format + " " + Width + "x" + Height);
}

// Texture extractor - reads from GPEG data stream using context info
// This type is parsed with GPEG data as the stream, not CPEG
type volition_peg_texture_extractor ui("Texture")
{
  // Get texture info from context (set by v10/v13 body before calling)
  tex_offset = ctx_get("_peg_extract_offset");
  tex_size = ctx_get("_peg_extract_size");
  tex_name = ctx_get("_peg_extract_name");
  tex_width = ctx_get("_peg_extract_width");
  tex_height = ctx_get("_peg_extract_height");
  tex_format = ctx_get("_peg_extract_format");

  set_name(tex_name);

  // Extract texture data from GPEG stream (this type receives GPEG data)
  seek(tex_offset);
  tex_data = read(tex_size);

  // Display texture metadata
  width = tex_width ui("Width");
  height = tex_height ui("Height");
  format = tex_format ui("Format");
  data_size = len(tex_data) ui("Data Size");
  offset = tex_offset ui("GPEG Offset");

  // Determine if this is a DXT format that can be previewed
  is_dxt = contains(tex_format, "DXT");

  if (is_dxt && len(tex_data) > 0) {
    // Set preview with raw DXT data
    // The image widget will attempt to decode based on extension
    set_preview(tex_name + ".dxt", tex_data);
    set_viewer("image");
  } else {
    // Non-DXT format - show as hex
    set_preview(tex_name + ".bin", tex_data);
    set_viewer("hex");
  }
}