#include "devs_internal.h"

static const void *buffer_data(devs_ctx_t *ctx, value_t v, unsigned *sz) {

if (!devs_is_buffer(ctx, v)) {

devs_throw_expecting_error(ctx, DEVS_BUILTIN_STRING_BUFFER, v);

return NULL;

}

return devs_buffer_data(ctx, v, sz);

}

static void *wr_buffer_data(devs_ctx_t *ctx, value_t v, unsigned *sz) {

if (!devs_buffer_is_writable(ctx, v)) {

devs_throw_expecting_error_ext(ctx, "mutable Buffer", v);

return NULL;

}

return devs_buffer_data(ctx, v, sz);

}

void fun1_Buffer_alloc(devs_ctx_t *ctx) {

unsigned sz = devs_arg_int(ctx, 0);

devs_ret_gc_ptr(ctx, devs_buffer_try_alloc(ctx, sz));

}

value_t prop_Buffer_length(devs_ctx_t *ctx, value_t self) {

unsigned sz;

if (buffer_data(ctx, self, &sz))

return devs_value_from_int(sz);

else

return devs_undefined;

}

void meth0_Buffer_toString(devs_ctx_t *ctx) {

unsigned sz;

const uint8_t *data = buffer_data(ctx, devs_arg_self(ctx), &sz);

if (data)

devs_ret(ctx, devs_string_from_utf8(ctx, data, sz));

}

void meth3_Buffer_fillAt(devs_ctx_t *ctx) {

unsigned dlen;

uint8_t *dst = wr_buffer_data(ctx, devs_arg_self(ctx), &dlen);

if (dst == NULL)

return;

unsigned dst_offset = devs_arg_int(ctx, 0);

unsigned len = devs_arg_int(ctx, 1);

unsigned val = devs_arg_int(ctx, 2);

if (dst_offset >= dlen)

return;

dlen -= dst_offset;

if (dlen < len)

len = dlen;

memset(dst + dst_offset, val, len);

}

void meth4_Buffer_blitAt(devs_ctx_t *ctx) {

unsigned slen, dlen;

uint8_t *dst = wr_buffer_data(ctx, devs_arg_self(ctx), &dlen);

if (dst == NULL)

return;

uint32_t dst_offset = devs_arg_int(ctx, 0);

value_t src_ = devs_arg(ctx, 1);

const uint8_t *src = devs_is_string(ctx, src_) ? devs_string_get_utf8(ctx, src_, &slen)

: buffer_data(ctx, src_, &slen);

if (src == NULL)

return;

uint32_t src_offset = devs_arg_int(ctx, 2);

uint32_t len = devs_arg_int(ctx, 3);

if (src_offset >= slen)

return;

slen -= src_offset;

if (slen < len)

len = slen;

if (dst_offset >= dlen)

return;

dlen -= dst_offset;

if (dlen < len)

len = dlen;

memcpy(dst + dst_offset, src + src_offset, len);

}