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#ifndef WP_COMPACT_TEXT_H
#define WP_COMPACT_TEXT_H

#include <stdbool.h>
#include <stddef.h>
#include <stdint.h>

/* Host-port helpers for compact text/token streams observed in the
 * decompiled DOS source.  These are deliberately small, deterministic
 * translations of the byte-walk behavior in:
 *   - firmware_io_compact_transfer_step @ 3000:05ad
 *   - firmware_io_no_op_return/firmware_io_flag_merge @ 3000:05bd/05c5
 *   - shell_expand_c0_escape_tokens_into_bx_buffer @ 4000:23ef
 */
typedef struct WpCompactStats {
    size_t input_bytes_consumed;
    size_t tokens_written;
    size_t bytes_written;
    size_t c0_word_tokens;
    size_t ff_tilde_escapes;
    size_t tilde_markers;
    bool hit_terminator;
    bool input_truncated;
    bool output_truncated;
} WpCompactStats;

void wp_compact_stats_clear(WpCompactStats *stats);

/* Decode a null-terminated compact byte stream into 16-bit host tokens.
 * Normal bytes become their unsigned value; 0xFF becomes literal '~';
 * 0x7E becomes 0xFC3A; and 0xC0 reads the following little-endian word and
 * advances over the four-byte C0 token envelope.  The terminating zero is not
 * counted in *out_count, but it is written as an extra zero token when there is
 * capacity, mirroring the decompiled *DI = 0 tail store. */
bool wp_compact_decode_token_stream(const uint8_t *src,
                                    size_t src_len,
                                    uint16_t *out,
                                    size_t out_capacity,
                                    size_t *out_count,
                                    WpCompactStats *stats);

/* Expand/canonicalize C0 escaped tokens in a byte stream.  When a source byte
 * is 0xC0, the two-byte word at source+1 is copied and a canonical trailing
 * 0xC0 is emitted, then the input advances by four bytes.  Non-C0 bytes copy
 * unchanged until the terminating zero is copied. */
bool wp_compact_expand_c0_escape_tokens(const uint8_t *src,
                                        size_t src_len,
                                        uint8_t *out,
                                        size_t out_capacity,
                                        size_t *out_len,
                                        WpCompactStats *stats);

#endif
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