Uses ANSI terminal colors and allows per-character customization to the
foreground and background. Includes a new `Artwork` constructor to color
automatically.

@@ -82,0 +89,4 @@
+ * first -> foreground color
+ * second -> bacground color
+ */
+const std::map<char, const std::pair<const int, const int>> colors = {

@@ -21,0 +79,4 @@
+    lines = colored_lines;
+}
+
+Artwork::Artwork(const std::string &raw, int offset, const char *raw_fg, const char *raw_bg) 

@@ -0,0 +49,4 @@
+TEST(Artwork, AllBackgrounds) {
+    Artwork art { "01234567\n89ABCDEF\n", 8};
+    art.color("        \n        ", "01234567\n89ABCDEF");
+    std::string expected {"\x1b[39;40m0\x1b[39;41m1\x1b[39;42m2\x1b[39;43m3\x1b[39;44m4\x1b[39;45m5\x1b[39;46m6\x1b[39;47m7\x1b[0m\n\x1b[39;100m8\x1b[39;101m9\x1b[39;102mA\x1b[39;103mB\x1b[39;104mC\x1b[39;105mD\x1b[39;106mE\x1b[39;107mF\x1b[0m"};

@@ -21,0 +35,4 @@
+    char curr_fg {' '};    
+    char curr_bg {' '};    
+    string_view fg {raw_fg};
+    string_view bg {raw_bg};

@@ -21,0 +38,4 @@
+    string_view bg {raw_bg};
+    ZipRange<string_view, string_view> color_delims {fg, bg};
+    ZipRange<string_view, string_view>::iterator iter_delims {color_delims.begin()};
+    ZipRange<string_view, string_view>::iterator end_delims {color_delims.end()};

@@ -21,0 +47,4 @@
+        for (int col {}; col < line_width; ++col, ++iter_delims) {
+            pair<char, char> color_pair {*iter_delims};
+            stringstream color_esc_seq {};
+            color_esc_seq << "\x1b[";

@@ -21,0 +50,4 @@
+            color_esc_seq << "\x1b[";
+
+            if (color_pair.first == '\n' || color_pair.second == '\n') {
+                throw runtime_error("Unexpected newline");

@@ -21,0 +56,4 @@
+            if (!artwork::COLORS.contains(color_pair.first) ||
+                !artwork::COLORS.contains(color_pair.second)
+            ) {
+                throw runtime_error("Invalid color delimiter");

@@ -21,0 +77,4 @@
+            pair<char, char> color_pair {*iter_delims};
+            if (color_pair.first == '\n' || color_pair.second == '\n') {
+                if (color_pair.first != color_pair.second) {
+                    throw runtime_error("Foreground/background not the same length.");

@@ -0,0 +25,4 @@
+{
+    Artwork art { "foo\nbar\nbaz\n", 3};
+    ASSERT_EQ(str(art), "foo\nbar\nbaz");
+    art.color( "   \n   \n   ", "   \n   \n   ");

@@ -0,0 +79,4 @@
+    ASSERT_EQ(str(art), "foo\nbar\nbaz");
+    ASSERT_THROW(
+        {art.color( "  \n \n   \n   ", "   \n   \n   ");},
+        runtime_error