#ifndef G474_BOOT_WRITER_H
#define G474_BOOT_WRITER_H
#include <stdbool.h>
#include <stdint.h>
#include <string.h>
/* ECC Flash must be programmed once per 64-bit word. Keep partial words in RAM
 * across SET packets; pad only the final word, without changing the image CRC. */
typedef bool (*g474_program_word)(void *user, uint32_t offset, uint64_t word);
typedef struct {
    uint32_t size, received;
    uint8_t pending[8];
    uint8_t used;
    bool failed;
} g474_writer;
static inline void g474_writer_init(g474_writer *w, uint32_t size)
{
    memset(w, 0, sizeof(*w)); w->size = size;
    memset(w->pending, 0xff, sizeof(w->pending));
}
static inline bool g474_writer_write(g474_writer *w, uint32_t offset,
    const uint8_t *data, uint16_t length, g474_program_word program, void *user)
{
    if (w->failed || !length || offset != w->received ||
        offset > w->size || length > w->size - offset) return false;
    while (length--) {
        w->pending[w->used++] = *data++; ++w->received;
        if (w->used == 8 || w->received == w->size) {
            uint64_t word;
            uint32_t start = w->received - w->used;
            memcpy(&word, w->pending, sizeof(word));
            if (!program(user, start, word)) { w->failed = true; return false; }
            w->used = 0; memset(w->pending, 0xff, sizeof(w->pending));
        }
    }
    return true;
}
#endif