feat: added colour code preview infobox

src/Infobox/ColourCode.c

@@ -0,0 +1,166 @@
+#include "ColourCode.h"
+#include <math.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+static const unsigned char HEX_VALS[256] = {
+    ['0'] = 0,  ['1'] = 1,  ['2'] = 2,  ['3'] = 3,  ['4'] = 4,  ['5'] = 5,
+    ['6'] = 6,  ['7'] = 7,  ['8'] = 8,  ['9'] = 9,  ['a'] = 10, ['b'] = 11,
+    ['c'] = 12, ['d'] = 13, ['e'] = 14, ['f'] = 15, ['A'] = 10, ['B'] = 11,
+    ['C'] = 12, ['D'] = 13, ['E'] = 14, ['F'] = 15,
+};
+
+static int is_hex_digit(char c) {
+  return HEX_VALS[(unsigned char)c] || c == '0';
+}
+
+static int is_valid_hex(const char *s, int len) {
+  if (len != 3 && len != 6)
+    return 0;
+  for (int i = 0; i < len; i++) {
+    if (!is_hex_digit(s[i]))
+      return 0;
+  }
+  return 1;
+}
+
+static void hex_to_rgb(const char *hex, int *r, int *g, int *b, int len) {
+  *r = *g = *b = 0;
+  if (len == 3) {
+    *r = HEX_VALS[(unsigned char)hex[0]] * 17;
+    *g = HEX_VALS[(unsigned char)hex[1]] * 17;
+    *b = HEX_VALS[(unsigned char)hex[2]] * 17;
+  } else if (len == 6) {
+    *r = HEX_VALS[(unsigned char)hex[0]] * 16 + HEX_VALS[(unsigned char)hex[1]];
+    *g = HEX_VALS[(unsigned char)hex[2]] * 16 + HEX_VALS[(unsigned char)hex[3]];
+    *b = HEX_VALS[(unsigned char)hex[4]] * 16 + HEX_VALS[(unsigned char)hex[5]];
+  }
+}
+
+static void rgb_to_hsl(int r, int g, int b, int *h, int *s, int *l) {
+  int max = r > g ? (r > b ? r : b) : (g > b ? g : b);
+  int min = r < g ? (r < b ? r : b) : (g < b ? g : b);
+  int delta = max - min;
+  *l = (max + min) / 2;
+  *s = 0;
+  *h = 0;
+  if (delta > 0) {
+    *s = (int)((double)delta / (1.0 - fabs(2.0 * *l / 255.0 - 1.0)) * 100.0);
+    if (max == r) {
+      *h = (int)(60.0 * fmod((double)(g - b) / delta, 6.0));
+    } else if (max == g) {
+      *h = (int)(60.0 * (((b - r) / delta) + 2.0));
+    } else {
+      *h = (int)(60.0 * (((r - g) / delta) + 4.0));
+    }
+    if (*h < 0)
+      *h += 360;
+  }
+}
+
+static void rgb_to_hsv(int r, int g, int b, int *h, int *s, int *v) {
+  int max = r > g ? (r > b ? r : b) : (g > b ? g : b);
+  int min = r < g ? (r < b ? r : b) : (g < b ? g : b);
+  int delta = max - min;
+  *v = max * 100 / 255;
+  *s = max > 0 ? delta * 100 / max : 0;
+  *h = 0;
+  if (delta > 0) {
+    if (max == r) {
+      *h = (int)(60.0 * fmod((double)(g - b) / delta, 6.0));
+    } else if (max == g) {
+      *h = (int)(60.0 * (((b - r) / delta) + 2.0));
+    } else {
+      *h = (int)(60.0 * (((r - g) / delta) + 4.0));
+    }
+    if (*h < 0)
+      *h += 360;
+  }
+}
+
+static void rgb_to_cmyk(int r, int g, int b, int *c, int *m, int *y, int *k) {
+  int max = r > g ? (r > b ? r : b) : (g > b ? g : b);
+  double kf = 1.0 - max / 255.0;
+  if (kf >= 0.99) {
+    *c = *m = *y = *k = 100;
+  } else {
+    *c = (int)((1.0 - r / 255.0 - kf) / (1.0 - kf) * 100);
+    *m = (int)((1.0 - g / 255.0 - kf) / (1.0 - kf) * 100);
+    *y = (int)((1.0 - b / 255.0 - kf) / (1.0 - kf) * 100);
+    *k = (int)(kf * 100);
+  }
+}
+
+int is_colour_code_query(const char *query) {
+  if (!query)
+    return 0;
+  const char *p = query;
+  if (p[0] == '#') {
+    p++;
+    while (*p == ' ')
+      p++;
+    const char *end = p;
+    while (is_hex_digit(*end))
+      end++;
+    int len = end - p;
+    return is_valid_hex(p, len);
+  }
+  return 0;
+}
+
+InfoBox fetch_colour_data(char *query) {
+  InfoBox info = {NULL, NULL, NULL, NULL};
+  if (!query)
+    return info;
+
+  const char *p = query;
+  if (p[0] != '#')
+    return info;
+  p++;
+  while (*p == ' ')
+    p++;
+  const char *end = p;
+  while (is_hex_digit(*end))
+    end++;
+  int len = end - p;
+  if (!is_valid_hex(p, len))
+    return info;
+
+  int r, g, b;
+  hex_to_rgb(p, &r, &g, &b, len);
+
+  int h, s, l;
+  rgb_to_hsl(r, g, b, &h, &s, &l);
+
+  int h2, s2, v;
+  rgb_to_hsv(r, g, b, &h2, &s2, &v);
+
+  int c, m, y, k;
+  rgb_to_cmyk(r, g, b, &c, &m, &y, &k);
+
+  char html[1024];
+  snprintf(html, sizeof(html),
+           "<div class='colour-container' style='line-height: 1.6;'>"
+           "<div style='display: flex; align-items: flex-start; gap: 16px;'>"
+           "<div style='width: 100px; height: 100px; border-radius: 12px; "
+           "border: 1px solid #ddd; background-color: #%.*s; flex-shrink: 0;'></div>"
+           "<div>"
+           "<div style='font-size: 1.3em; font-weight: bold; margin-bottom: 8px;'>"
+           "#%.*s</div>"
+           "<div style='color: #666; margin-bottom: 4px;'>RGB(%d, %d, %d)</div>"
+           "<div style='color: #666; margin-bottom: 4px;'>HSL(%d, %d%%, %d%%)</div>"
+           "<div style='color: #666; margin-bottom: 4px;'>HSV(%d, %d%%, %d%%)</div>"
+           "<div style='color: #666;'>CMYK(%d%%, %d%%, %d%%, %d%%)</div>"
+           "</div>"
+           "</div>"
+           "</div>",
+           len, p, len, p, r, g, b, h, s, l, h2, s2, v, c, m, y, k);
+
+  info.title = strdup("Colour");
+  info.extract = strdup(html);
+  info.thumbnail_url = NULL;
+  info.url = strdup("#");
+
+  return info;
+}

src/Infobox/ColourCode.h

@@ -0,0 +1,9 @@
+#ifndef COLOURCODE_H
+#define COLOURCODE_H
+
+#include "Infobox.h"
+
+int is_colour_code_query(const char *query);
+InfoBox fetch_colour_data(char *query);
+
+#endif

src/Routes/Search.c

@@ -1,6 +1,7 @@
 #include "Search.h"
 #include "../Cache/Cache.h"
 #include "../Infobox/Calculator.h"
+#include "../Infobox/ColourCode.h"
 #include "../Infobox/CurrencyConversion.h"
 #include "../Infobox/Dictionary.h"
 #include "../Infobox/UnitConversion.h"
@@ -216,11 +217,16 @@ static int is_calculator_query(const char *query) {
   return 0;
 }
 
+static InfoBox fetch_colour_wrapper(char *query) {
+  return fetch_colour_data(query);
+}
+
 static InfoBoxHandler handlers[] = {
     {is_dictionary_query, fetch_dict_wrapper, NULL},
     {is_calculator_query, fetch_calc_wrapper, NULL},
     {is_unit_conv_query, fetch_unit_wrapper, NULL},
     {is_currency_query, fetch_currency_wrapper, NULL},
+    {is_colour_code_query, fetch_colour_wrapper, NULL},
     {always_true, fetch_wiki_wrapper, construct_wiki_url},
 };
 enum { HANDLER_COUNT = sizeof(handlers) / sizeof(handlers[0]) };