m_snowman OK (#94)

* moved everything from private fork

* trying to figure out name stuff

* matched mSN_check_life

* fully matching

* add season enum

* forgot

* fixed structs

src/code/m_snowman.c

@@ -0,0 +1,143 @@
+/**
+ * @file m_snowman.c
+ *
+ * Manages data associated with snowmen.
+ *
+ * This data is stored in the SnowmanData struct in the save file.
+ * There can be three snowmen built at a single time. Each snowman has 3 variations depending on how melted they are.
+ * The first snowman uses the names SNOWMAN0, SNOWMAN1, and SNOWMAN2, the second snowman uses SNOWMAN3, SNOWMAN4, and
+ * SNOWMAN5, etc.
+ *
+ */
+
+#include "global.h"
+#include "m_snowman.h"
+#include "m_common_data.h"
+#include "m_field_info.h"
+#include "m_police_box.h"
+#include "m_lib.h"
+#include "libc64/qrand.h"
+#include "m_name_table.h"
+
+/**
+ * After advancing daysElapsed days, is the snowman completely melted?
+ *
+ * @return True if the snowman is alive, False if the snowman is dead.
+ */
+s32 mSN_check_life(u16* name, s32 daysElapsed) {
+    s32 ret = false;
+
+    // Snowmen outside of winter die regardless of daysElapsed.
+    if (common_data.time.season == WINTER) {
+        s32 snowmanAge = ((*name - SNOWMAN0) % SNOWMAN_SAVE_COUNT);
+
+        if (snowmanAge + daysElapsed < 3) {
+            ret = true;
+        }
+    }
+
+    return ret;
+}
+
+void mSN_ClearSnowmanData(u16* name, s32 snowmanIndex) {
+    bzero(&common_data.snowmanData[snowmanIndex], sizeof(SnowmanData));
+    *name = 0;
+}
+
+s32 mSN_ClearSnowman(u16* name) {
+    s32 ret = 0;
+
+    if ((*name >= SNOWMAN0) && (*name <= SNOWMAN8)) {
+        s32 snowmanIndex = (*name - SNOWMAN0) / SNOWMAN_SAVE_COUNT;
+
+        mSN_ClearSnowmanData(name, snowmanIndex);
+        ret = 1;
+    }
+
+    return ret;
+}
+
+/**
+ * Modify a snowman according to how many days have passed.
+ *
+ * @return 0 if the actor isn't a snowman. 1 if the actor is a snowman.
+ */
+s32 mSN_MeltSnowman(u16* name, s32 daysElapsed) {
+    s32 ret = 0;
+
+    if ((*name >= SNOWMAN0) && (*name <= SNOWMAN8)) {
+        s32 snowmanIndex = (*name - SNOWMAN0) / SNOWMAN_SAVE_COUNT;
+
+        if (daysElapsed < 0) {
+            daysElapsed = 1;
+            common_data.snowmanYear = 0;
+            common_data.snowmanMonth = 0;
+            common_data.snowmanDay = 0;
+            common_data.snowmanHour = 0;
+        }
+
+        if (!mSN_check_life(name, daysElapsed)) {
+            mSN_ClearSnowmanData(name, snowmanIndex);
+
+        } else {
+            SnowmanData* snowmanData = &common_data.snowmanData[snowmanIndex];
+
+            *name += daysElapsed;
+
+            while (daysElapsed) {
+                snowmanData->headSize = (u8)(s32)(snowmanData->headSize * 0.8f);
+                snowmanData->bodySize = (u8)(s32)(snowmanData->bodySize * 0.8f);
+                daysElapsed--;
+            }
+        }
+
+        ret = 1;
+    }
+
+    return ret;
+}
+
+/**
+ * Find a slot in SnowmanData that isn't occupied by a snowman.
+ *
+ * @return the index of the first empty slot. If there are no empty slots, return -1.
+ */
+s32 mSN_get_free_space(void) {
+    SnowmanData* snowmanData = common_data.snowmanData;
+    s32 snowmanIndex;
+
+    for (snowmanIndex = 0; snowmanIndex < SNOWMAN_SAVE_COUNT; snowmanIndex++) {
+        if (!snowmanData[snowmanIndex].exists) {
+            return snowmanIndex;
+        }
+    }
+
+    return -1;
+}
+
+void mSN_regist_snowman_society(SnowmanInfo* snowmanInfo) {
+    u16 sp2E = *mFI_GetUnitFG(snowmanInfo->position);
+    s32 snowmanIndex = mSN_get_free_space();
+    u16 name;
+
+    if (snowmanIndex != -1) {
+        mem_copy(&common_data.snowmanData[snowmanIndex], snowmanInfo, sizeof(SnowmanData));
+
+        if (sp2E) {
+            mPB_keep_item(sp2E);
+            mFI_Wpos2DepositOFF(snowmanInfo->position);
+        }
+
+        name = snowmanIndex * SNOWMAN_SAVE_COUNT + SNOWMAN0;
+        mFI_SetFG_common(name, snowmanInfo->position, 1);
+    }
+}
+
+void mSN_decide_msg(void) {
+    common_data.unk_1074C = fqrand() * 3.0f;
+}
+
+void mSN_snowman_init(void) {
+    bzero(common_data.snowmanData, sizeof(SnowmanData[SNOWMAN_SAVE_COUNT]));
+    mSN_decide_msg();
+}