From 9f22c21f174f404b605e52e7e88bad61d6a71509 Mon Sep 17 00:00:00 2001
From: Skot Croshere <skot@geocene.com>
Date: Mon, 19 Jun 2023 22:35:55 -0400
Subject: [PATCH] added suffixes to best_difficulty display

---
 main/system.c | 64 ++++++++++++++++++++++++++++++++++++++++++++++++++-
 main/system.h |  3 +++
 2 files changed, 66 insertions(+), 1 deletion(-)

diff --git a/main/system.c b/main/system.c
index 585f1845..e5c50180 100644
--- a/main/system.c
+++ b/main/system.c
@@ -23,6 +23,8 @@ static const char *TAG = "SystemModule";
 
 #define BM1397_VOLTAGE CONFIG_BM1397_VOLTAGE
 
+static void _suffix_string(uint64_t, char *, size_t, int);
+
 
 static void _init_system(SystemModule* module) {
 
@@ -38,6 +40,8 @@ static void _init_system(SystemModule* module) {
     module->lastClockSync = 0;
     module->FOUND_BLOCK = false;
 
+    _suffix_string(0, module->best_diff_string, DIFF_STRING_SIZE, 0);
+
     //test the LEDs
     // ESP_LOGI(TAG, "Init LEDs!");
     // ledc_init();
@@ -106,7 +110,7 @@ static void _update_best_diff(SystemModule* module){
     }
     OLED_clearLine(3);
     memset(module->oled_buf, 0, 20);
-    snprintf(module->oled_buf, 20, module->FOUND_BLOCK ? "!!! BLOCK FOUND !!!" : "BD: %u",  module->best_nonce_diff);
+    snprintf(module->oled_buf, 20, module->FOUND_BLOCK ? "!!! BLOCK FOUND !!!" : "BD: %s",  module->best_diff_string);
     OLED_writeString(0, 3, module->oled_buf);
 }
 
@@ -208,6 +212,8 @@ static void _check_for_best_diff(SystemModule * module, double diff, uint32_t nb
         return;
     }
     module->best_nonce_diff = diff;
+    //make the best_nonce_diff into a string
+    _suffix_string((uint64_t)diff, module->best_diff_string, DIFF_STRING_SIZE, 0);
     double network_diff = _calculate_network_difficulty(nbits);
     if(diff > network_diff){
         module->FOUND_BLOCK = true;
@@ -216,6 +222,62 @@ static void _check_for_best_diff(SystemModule * module, double diff, uint32_t nb
     ESP_LOGI(TAG, "Network diff: %f", network_diff);
 }
 
+/* Convert a uint64_t value into a truncated string for displaying with its
+ * associated suitable for Mega, Giga etc. Buf array needs to be long enough */
+static void _suffix_string(uint64_t val, char *buf, size_t bufsiz, int sigdigits) {
+	const double  dkilo = 1000.0;
+	const uint64_t kilo = 1000ull;
+	const uint64_t mega = 1000000ull;
+	const uint64_t giga = 1000000000ull;
+	const uint64_t tera = 1000000000000ull;
+	const uint64_t peta = 1000000000000000ull;
+	const uint64_t exa  = 1000000000000000000ull;
+	char suffix[2] = "";
+	bool decimal = true;
+	double dval;
+
+	if (val >= exa) {
+		val /= peta;
+		dval = (double)val / dkilo;
+		strcpy(suffix, "E");
+	} else if (val >= peta) {
+		val /= tera;
+		dval = (double)val / dkilo;
+		strcpy(suffix, "P");
+	} else if (val >= tera) {
+		val /= giga;
+		dval = (double)val / dkilo;
+		strcpy(suffix, "T");
+	} else if (val >= giga) {
+		val /= mega;
+		dval = (double)val / dkilo;
+		strcpy(suffix, "G");
+	} else if (val >= mega) {
+		val /= kilo;
+		dval = (double)val / dkilo;
+		strcpy(suffix, "M");
+	} else if (val >= kilo) {
+		dval = (double)val / dkilo;
+		strcpy(suffix, "K");
+	} else {
+		dval = val;
+		decimal = false;
+	}
+
+	if (!sigdigits) {
+		if (decimal)
+			snprintf(buf, bufsiz, "%.3g%s", dval, suffix);
+		else
+			snprintf(buf, bufsiz, "%d%s", (unsigned int)dval, suffix);
+	} else {
+		/* Always show sigdigits + 1, padded on right with zeroes
+		 * followed by suffix */
+		int ndigits = sigdigits - 1 - (dval > 0.0 ? floor(log10(dval)) : 0);
+
+		snprintf(buf, bufsiz, "%*.*f%s", sigdigits + 1, ndigits, dval, suffix);
+	}
+}
+
 
 void SYSTEM_task(void *pvParameters) {
 
diff --git a/main/system.h b/main/system.h
index d149cd97..d1d41da1 100644
--- a/main/system.h
+++ b/main/system.h
@@ -3,6 +3,8 @@
 
 #define HISTORY_LENGTH 100
 #define HISTORY_WINDOW_SIZE 5
+
+#define DIFF_STRING_SIZE 10
 typedef struct {
     double duration_start;
     int historical_hashrate_rolling_index;
@@ -16,6 +18,7 @@ typedef struct {
     int screen_page;
     char oled_buf[20];
     uint32_t best_nonce_diff;
+    char best_diff_string[DIFF_STRING_SIZE];
     bool FOUND_BLOCK;
 
     uint32_t lastClockSync;