1 files changed, 178 insertions, 0 deletions

diff --git a/src/core/cube.h b/src/core/cube.h
index ce8a6b8..a045e55 100644
--- a/src/core/cube.h
+++ b/src/core/cube.h
@@ -174,3 +174,181 @@ getcube(int64_t ep, int64_t eo, int64_t cp, int64_t co)
 
         return cubefromarray(carr, earr);
 }
+
+
+/******************************************************************************/
+
+STATIC cube_t readcube(const char *);
+STATIC int64_t writecube(cube_t, size_t n, char [n]);
+STATIC uint8_t readco(const char *);
+STATIC uint8_t readcp(const char *);
+STATIC uint8_t readeo(const char *);
+STATIC uint8_t readep(const char *);
+
+STATIC uint8_t b32toedge(char);
+STATIC uint8_t b32tocorner(char);
+STATIC char edgetob32(uint8_t);
+STATIC char cornertob32(uint8_t);
+
+STATIC uint8_t
+readco(const char *str)
+{
+        if (*str == '0')
+                return 0;
+        if (*str == '1')
+                return CTWIST_CW;
+        if (*str == '2')
+                return CTWIST_CCW;
+
+        LOG("Error reading CO\n");
+        return UINT8_ERROR;
+}
+
+STATIC uint8_t
+readcp(const char *str)
+{
+        uint8_t c;
+
+        for (c = 0; c < 8; c++)
+                if (!strncmp(str, cornerstr[c], 3) ||
+                    !strncmp(str, cornerstralt[c], 3))
+                        return c;
+
+        LOG("Error reading CP\n");
+        return UINT8_ERROR;
+}
+
+STATIC uint8_t
+readeo(const char *str)
+{
+        if (*str == '0')
+                return 0;
+        if (*str == '1')
+                return EFLIP;
+
+        LOG("Error reading EO\n");
+        return UINT8_ERROR;
+}
+
+STATIC uint8_t
+readep(const char *str)
+{
+        uint8_t e;
+
+        for (e = 0; e < 12; e++)
+                if (!strncmp(str, edgestr[e], 2))
+                        return e;
+
+        LOG("Error reading EP\n");
+        return UINT8_ERROR;
+}
+
+STATIC cube_t
+readcube(const char *buf)
+{
+        int i;
+        uint8_t c[8], e[12];
+
+        for (i = 0; i < 8; i++) {
+                c[i] = b32tocorner(buf[i]);
+                if (c[i] == UINT8_ERROR) {
+                        LOG("Error reading corner %d ", i);
+                        if (buf[i] == 0) {
+                                LOG("(string terminated early)\n");
+                        } else {
+                                LOG("(char '%c')\n", buf[i]);
+                        }
+                        return ZERO_CUBE;
+                }
+        }
+
+        if (buf[8] != '=') {
+                LOG("Error reading separator: a single '=' "
+                    "must be used to separate edges and corners\n");
+                return ZERO_CUBE;
+        }
+
+        for (i = 0; i < 12; i++) {
+                e[i] = b32toedge(buf[i+9]);
+                if (e[i] == UINT8_ERROR) {
+                        LOG("Error reading edge %d ", i);
+                        if (buf[i+9] == 0) {
+                                LOG("(string terminated early)\n");
+                        } else {
+                                LOG("(char '%c')\n", buf[i+9]);
+                        }
+                        return ZERO_CUBE;
+                }
+        }
+
+        return cubefromarray(c, e);
+}
+
+STATIC int64_t
+writecube(cube_t cube, size_t buf_size, char buf[buf_size])
+{
+        int i;
+        uint8_t corner[8], edge[12];
+
+        if (buf_size < NISSY_SIZE_CUBE) {
+                LOG("Cannot write cube: buffer size must be at least %u "
+                    "bytes, but the provided one is %zu bytes.\n",
+                    NISSY_SIZE_CUBE, buf_size);
+                return NISSY_ERROR_BUFFER_SIZE;
+        }
+
+        pieces(&cube, corner, edge);
+
+        for (i = 0; i < 8; i++)
+                buf[i] = cornertob32(corner[i]);
+
+        buf[8] = '=';
+
+        for (i = 0; i < 12; i++)
+                buf[i+9] = edgetob32(edge[i]);
+
+/* TODO */
+        buf[21] = '=';
+        buf[22] = 'A';
+        buf[23] = '\0';
+
+        return NISSY_OK;
+}
+
+STATIC uint8_t
+b32toedge(char c)
+{
+        if (!((c >= 'A' && c <= 'Z') || (c >= 'a' && c <= 'f')))
+                return UINT8_ERROR;
+
+        return c <= 'Z' ? (uint8_t)(c - 'A') : (uint8_t)(c - 'a') + 26;
+}
+
+STATIC uint8_t
+b32tocorner(char c) {
+        uint8_t val;
+
+        if (!((c >= 'A' && c <= 'Z') || (c >= 'a' && c <= 'f')))
+                return UINT8_ERROR;
+
+        val = c <= 'Z' ? (uint8_t)(c - 'A') : (uint8_t)(c - 'a') + 26;
+
+        return (val & 7) | ((val & 24) << 2);
+}
+
+STATIC char
+edgetob32(uint8_t edge)
+{
+        return edge < 26 ? 'A' + (char)edge : 'a' + (char)(edge - 26);
+}
+
+STATIC char
+cornertob32(uint8_t corner)
+{
+        uint8_t val;
+
+        val = (corner & 7) | ((corner & 96) >> 2);
+
+        return val < 26 ? 'A' + (char)val : 'a' + (char)(val - 26);
+}
+/******************************************************************************/