implement mode history

1 files changed, 25 insertions, 5 deletions

diff --git a/robot/modes.c b/robot/modes.c
index 1f36703..8d3a099 100644
--- a/robot/modes.c
+++ b/robot/modes.c
@@ -1,15 +1,31 @@
+#include <stdbool.h>
+
+#include "../shared/util.h"
+#include "errcatch.h"
 #include "modes.h"
 #include "sercomm.h"
 
-void (*g_w2_current_mode)() = &w2_mode_halt;
+/** function pointer to current mode */
+// static void (*g_w2_current_mode)() = &w2_mode_halt;
+
+static void (*g_w2_mode_history[W2_MODE_HISTORY_BUFFER_SIZE])();
+static uint8_t g_w2_mode_history_index = 0;
+
+void w2_modes_main() { (*g_w2_mode_history[g_w2_mode_history_index])(); }
 
-void w2_modes_main() { (*g_w2_current_mode)(); }
+void w2_modes_switch(w2_e_mode new_mode, bool replace) {
+	int16_t next_history_index =
+		g_w2_mode_history_index + (new_mode == W2_M_PREV ? -1 : 1) * (replace - 1);
+	if (next_history_index == -1 || next_history_index == W2_MODE_HISTORY_BUFFER_SIZE - 1) {
+		next_history_index = W2_RANGE(0, next_history_index, W2_MODE_HISTORY_BUFFER_SIZE);
+		w2_errcatch_throw(W2_E_WARN_MODE_HISTORY_BUFFER_IOB);
+	}
 
-void w2_modes_switch(w2_e_mode new_mode) {
 	if (new_mode == W2_M_PREV) {
-		// TODO implement previous mode buffer
+		g_w2_mode_history_index = next_history_index;
 	} else {
-		g_w2_current_mode = W2_MODES[new_mode];
+		g_w2_mode_history_index					   = next_history_index;
+		g_w2_mode_history[g_w2_mode_history_index] = W2_MODES[new_mode];
 	}
 
 	// forward mode change to sercomm
@@ -22,3 +38,7 @@ void w2_modes_switch(w2_e_mode new_mode) {
 	free(msg);
 	free(msg_bin);
 }
+
+void w2_modes_call(w2_e_mode mode) { w2_modes_switch(mode, false); }
+
+void w2_modes_swap(w2_e_mode mode) { w2_modes_switch(mode, true); }