1 files changed, 76 insertions, 12 deletions

diff --git a/main/i2c.c b/main/i2c.c
index f366793..e1563a0 100644
--- a/main/i2c.c
+++ b/main/i2c.c
@@ -8,36 +8,82 @@
 
 #include "i2c.h"
 #include "pb-mod.h"
-#include "pbdrv.h"
 #include "config.h"
 #include "pb-buf.h"
 #include "pb-send.h"
 
-i2c_addr_t modules[CFG_PB_MOD_MAX];
+static pb_global_state_t _global_state = PB_GS_IDLE;
+pb_puzzle_module_t modules[CFG_PB_MOD_MAX];
+// stolen from lib/pico-sdk/src/rp2_common/hardware_i2c/i2c.c
+#define i2c_reserved_addr(addr) (((addr) & 0x78) == 0 || ((addr) & 0x78) == 0x78)
 size_t modules_size = 0;
 
-static void state_exchange() {
+static void bus_scan() {
+	pb_buf_t buf = pb_send_magic_req();
+
+	// check for all 7-bit addresses
+	uint16_t addr_max = 1 << 7;
+	for (uint16_t addr = 0x00; addr < addr_max; addr++) {
+		if (i2c_reserved_addr(addr)) continue;
+		if (addr == PB_MOD_ADDR) continue;
+
+		pb_i2c_send(addr, (uint8_t *) buf.data, buf.size);
+	}
+
+	pb_buf_free(&buf);
+}
+
+static void update_state() {
+	int idle = 0, playing = 0, solved = 0;
+
+	// count # of modules in each state
 	for (size_t i = 0; i < modules_size; i++) {
-		pb_buf_t buf = pb_send_state_req();
-		
-		pb_buf_free(&buf);
+		pb_global_state_t state = modules[i].state;
+		if (state == PB_GS_IDLE) idle++;
+		else if (state == PB_GS_PLAYING) playing++;
+		else if (state == PB_GS_SOLVED) solved++;
+	}
+
+	if (idle == modules_size) { // if all modules are in PB_GS_IDLE
+		pb_hook_mod_state_write(PB_GS_IDLE);
+	} else if (solved == modules_size) { // if all modules are in PB_GS_SOLVED
+		pb_hook_mod_state_write(PB_GS_SOLVED);
+	} else {
+		pb_hook_mod_state_write(PB_GS_PLAYING);
 	}
+
+	// if a module is still playing, don't promote a next one to playing module
+	if (playing > 0) return;
+
+	for (size_t i = 0; i < modules_size; i++) {
+		// find first module that is idle
+		pb_global_state_t	module_state = modules[i].state;
+		if (module_state != PB_GS_IDLE) continue;
+
+		pb_buf_t buff = pb_send_state_set(PB_GS_PLAYING);
+		pb_i2c_send(modules[i].sender, (uint8_t*)buff.data, buff.size);
+		pb_buf_free(&buff);
+	}
+}
+
+static void state_exchange() {
+	update_state();
+	pb_buf_t buf = pb_send_state_req();
+	for (size_t i = 0; i < modules_size; i++)
+		pb_i2c_send(modules[i].sender, (uint8_t *) buf.data, buf.size);
+	pb_buf_free(&buf);
 }
 
 void bus_task() {
 	// do a scan of the bus
 	bus_scan();
 
-	// FIXME: this should be removed (see handover: RP2040 I2C limitations)
-	// wait for 5 seconds until all handshake responses are received
-	pb_mod_blocking_delay_ms(5e3);
-
 	while(1) {
 		// send my state to all puzzle modules
 		state_exchange();
 
 		// wait 1 second
-		pb_mod_blocking_delay_ms(1e3);
+		vTaskDelay(1e3 / portTICK_PERIOD_MS);
 	}
 }
 
@@ -54,7 +100,25 @@ void bus_task() {
  */
 void pb_route_cmd_magic_res(pb_msg_t * msg) {
 	if (modules_size == CFG_PB_MOD_MAX) return;
-	modules[modules_size++] = msg->sender;
+	pb_puzzle_module_t tmp_module = {msg->sender, PB_GS_NOINIT};
+	modules[modules_size++] = tmp_module;
 	printf("i2c: registered puzzle module w/ address 0x%02x\n", msg->sender);
 }
 
+void pb_route_cmd_state_res(pb_msg_t * msg) {
+	pb_cmd_state_t * cmd = msg->cmd;
+	i2c_addr_t sender = msg->sender;
+
+	for (size_t i = 0; i < modules_size; i++) {
+		if (modules[i].sender != sender) continue;
+		modules[i].state = cmd->state;
+	}
+}
+
+pb_global_state_t pb_hook_mod_state_read() {
+	return _global_state;
+}
+
+void pb_hook_mod_state_write(pb_global_state_t state) {
+	_global_state = state;
+}