// -*- mode: c++; c-basic-offset: 2; -*-

#include "common.hh"

#include <string.h>

#include "gui_attrtext.hh"
#include "gui_hexdump.hh"

namespace {

AttributedText::Attribute const addr(0x90, 0x90, 0x90);

inline size_t append(char* out, size_t max, char const* in, size_t len) {
  if (len <= max) {
    memcpy(out, in, len);
    return len;
  }
  return 0;
}

inline size_t safe(char* out, size_t max, char const* in, size_t len) {
  size_t ret = 0;
  for (; len--; ++in) {
    if (*in >= ' ' && *in < '\x7f') {
      ret += append(out + ret, max - ret, in, 1);
      continue;
    }
    switch (*in) {
    case '\r':
      ret += append(out + ret, max - ret, "\xe2\x86\xb5", 3);  // U+21B5
      break;
    case '\n':
      ret += append(out + ret, max - ret, "\xc2\xb6", 2);  // U+00B6
      break;
    case '\x8':
      ret += append(out + ret, max - ret, "\xe2\x8c\xab", 3);  // U+232B
      break;
    case '\t':
      ret += append(out + ret, max - ret, "\xe2\x86\xb9", 3);  // U+21B9
      break;
    default:
      ret += append(out + ret, max - ret, "\xef\xbf\xbd", 3);  // U+FFFD
      break;
    }
  }
  return ret;
}

}  // namespace


// static
void HexDump::write(AttributedText* text, uint8_t flags, std::string const& str,
                    size_t start, size_t length) {
  if (start >= str.size()) return;
  length = std::min(length, str.size() - start);
  if (length == 0) return;

  AttributedText::Attribute box(0x90, 0x90, 0x90);
  box.set_bold(true);

  size_t i = 0;
  auto data = str.data() + start;
  char tmp[80];
  char tmp2[64];
  int len;
  while (i + 16 <= length) {
    if (flags & ADDRESS) {
      len = snprintf(tmp, sizeof(tmp), "%08lx  ", static_cast<unsigned long>(i));
      text->append(tmp, len, addr);
    }
    auto x = tmp2;
    for (char c = 0; c < 2; ++c) {
      len = snprintf(tmp, sizeof(tmp), "%02x %02x %02x %02x %02x %02x %02x %02x",
                     data[i] & 0xff, data[i + 1] & 0xff, data[i + 2] & 0xff,
                     data[i + 3] & 0xff, data[i + 4] & 0xff, data[i + 5] & 0xff,
                     data[i + 6] & 0xff, data[i + 7] & 0xff);
      if (flags & CHARS) {
        x += safe(x, sizeof(tmp2) - (x - tmp2), data + i, 8);
      }
      i += 8;
      text->append(tmp, len);
      if (c == 0) text->append("  ", 2);
    }
    if (flags & CHARS) {
      text->append("  |", 3, box);
      text->append(tmp2, x - tmp2);
      text->append("|\n", 2, box);
    } else {
      text->append("\n", 1);
    }
  }
  if (i < length) {
    if (flags & ADDRESS) {
      len = snprintf(tmp, sizeof(tmp), "%08lx  ", static_cast<unsigned long>(i));
      text->append(tmp, len, addr);
    }
    auto x = tmp2;
    if (i + 8 <= length) {
      len = snprintf(tmp, sizeof(tmp), "%02x %02x %02x %02x %02x %02x %02x %02x",
                     data[i] & 0xff, data[i + 1] & 0xff, data[i + 2] & 0xff,
                     data[i + 3] & 0xff, data[i + 4] & 0xff, data[i + 5] & 0xff,
                     data[i + 6] & 0xff, data[i + 7] & 0xff);
      if (flags & CHARS) {
        x += safe(x, sizeof(tmp2) - (x - tmp2), data + i, 8);
      }
      i += 8;
      text->append(tmp, len);
      text->append("  ");
    }
    for (; i < length; ++i) {
      len = snprintf(tmp, sizeof(tmp), "%02x ", data[i] & 0xff);
      if (flags & CHARS) x += safe(x, sizeof(tmp2) - (x - tmp2), data + i, 1);
      text->append(tmp, len);
    }
    if (flags & CHARS) {
      auto extra = 16 - length % 16;
      extra = extra * 3 + (extra > 8 ? 1 : 0);
      memset(tmp, ' ', extra);
      text->append(tmp, extra);
      text->append(" |", 2, box);
      text->append(tmp2, x - tmp2);
      text->append("|\n", 2, box);
    } else {
      text->append("\n", 1);
    }
    if (flags & ADDRESS) {
      len = snprintf(tmp, sizeof(tmp), "%08lx\n",
                     static_cast<unsigned long>(length));
      text->append(tmp, len, addr);
    }
  }
}

// static
uint8_t const HexDump::ADDRESS = 1 << 0;
// static
uint8_t const HexDump::CHARS = 1 << 1;