// Copyright 2017 The Wuffs Authors.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//    https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

use "std/lzw"

pub status "#bad extension label"
pub status "#bad frame size"
pub status "#bad graphic control"
pub status "#bad header"
pub status "#bad literal width"
pub status "#bad palette"

pri status "#internal error: inconsistent ri/wi"

pub const DECODER_WORKBUF_LEN_MAX_INCL_WORST_CASE : base.u64 = 0

// See the spec appendix E "Interlaced Images" on page 29. The first element
// represents either that the frame was non-interlaced, or that all interlace
// stages are complete. Otherwise, the four interlace stages are elements 4, 3,
// 2 and 1 in descending order. For example, the start and delta for the first
// interlace stage is 0 and 8, for the second interlace stage is 4 and 8, etc.
// For interlaced frames, the decoder.interlace field starts at 4 and is
// decremented towards 0.
//
// INTERLACE_START[0] is a special case. For non-interlaced frames, that
// element is never accessed. For interlaced frames, that element is only
// accessed after all interlace stages are complete. Being the maximum base.u32
// value means that, after all interlace stages are complete, dst_y will be set
// to that maximum value (and therefore outside the frame rect).
pri const INTERLACE_START : array[5] base.u32 = [0xFFFF_FFFF, 1, 2, 4, 0]
pri const INTERLACE_DELTA : array[5] base.u8 = [1, 2, 4, 8, 8]
pri const INTERLACE_COUNT : array[5] base.u8 = [0, 1, 2, 4, 8]

// ANIMEXTS1DOT0 is "ANIMEXTS1.0" as bytes.
pri const ANIMEXTS1DOT0 : array[11] base.u8 = [
	0x41, 0x4E, 0x49, 0x4D, 0x45, 0x58, 0x54, 0x53, 0x31, 0x2E, 0x30,
]

// NETSCAPE2DOT0 is "NETSCAPE2.0" as bytes.
pri const NETSCAPE2DOT0 : array[11] base.u8 = [
	0x4E, 0x45, 0x54, 0x53, 0x43, 0x41, 0x50, 0x45, 0x32, 0x2E, 0x30,
]

// ICCRGBG1012 Is "ICCRGBG1012" as bytes.
pri const ICCRGBG1012 : array[11] base.u8 = [
	0x49, 0x43, 0x43, 0x52, 0x47, 0x42, 0x47, 0x31, 0x30, 0x31, 0x32,
]

// XMPDATAXMP IS "XMP DataXMP" as bytes.
pri const XMPDATAXMP : array[11] base.u8 = [
	0x58, 0x4D, 0x50, 0x20, 0x44, 0x61, 0x74, 0x61, 0x58, 0x4D, 0x50,
]