Refactor asset loading

src/asset/asset.c

@@ -9,22 +9,23 @@
 #include "util/memory.h"
 #include "util/string.h"
 #include "assert/assert.h"
+#include "asset/assettype.h"
 
 errorret_t assetInit(void) {
-  memoryZero(&ASSET_MANAGER, sizeof(assetmanager_t));
-  
-  // Default system path, intended to be overridden by the paltform
-  stringCopy(ASSET_MANAGER.systemPath, ".", FILENAME_MAX);
+  memoryZero(&ASSET, sizeof(asset_t));
+
+  // Default system path, intended to be overridden by the platform
+  stringCopy(ASSET.systemPath, ".", FILENAME_MAX);
 
   // Open zip file
   char_t searchPath[FILENAME_MAX];
-  char_t **path = ASSET_SEARCH_PATHS;
+  const char_t **path = ASSET_SEARCH_PATHS;
   do {
     sprintf(
       searchPath,
       *path,
-      ASSET_MANAGER.systemPath,
-      ASSET_ASSET_FILE
+      ASSET.systemPath,
+      ASSET_FILE
     );
 
     // Try open
@@ -39,13 +40,61 @@ errorret_t assetInit(void) {
   errorOk();
 }
 
-erroret_t assetLoad(const char_t *filename, void *output) {
+errorret_t assetLoad(const char_t *filename, void *output) {
+  assertStrLenMax(filename, FILENAME_MAX, "Filename too long.");
+  assertNotNull(output, "Output pointer cannot be NULL.");
+
+  // Try to open the file
+  zip_file_t *file = zip_fopen(ASSET.zip, filename, 0);
+  if(file == NULL) {
+    errorThrow("Failed to open asset file: %s", filename);
+  }
+
+  // Read the header.
+  assetheader_t header;
+  memoryZero(&header, sizeof(assetheader_t));
+  zip_int64_t bytesRead = zip_fread(file, &header, sizeof(assetheader_t));
+  if(bytesRead != sizeof(assetheader_t)) {
+    zip_fclose(file);
+    errorThrow("Failed to read asset header for: %s", filename);
+  }
+
+  // Find the asset type based on the header
+  const assettypedef_t *def = NULL;
+  for(uint_fast8_t i = 0; i < ASSET_TYPE_COUNT; i++) {
+    if(ASSET_TYPE_DEFINITIONS[i].header == NULL) continue;
+    if(strcmp(header.header, ASSET_TYPE_DEFINITIONS[i].header) != 0) continue;
+    def = &ASSET_TYPE_DEFINITIONS[i];
+    break;
+  }
+  if(def == NULL) {
+    zip_fclose(file);
+    errorThrow("Unknown asset type for file: %s", filename);
+  }
+
+  // We found the asset type, now load the asset data
+  assertNotNull(def->load, "Asset load function cannot be NULL.");
+  void *data = memoryAllocate(def->dataSize);
+  bytesRead = zip_fread(file, data, def->dataSize);
+  if(bytesRead == 0 || bytesRead > def->dataSize) {
+    memoryFree(data);
+    zip_fclose(file);
+    errorThrow("Failed to read asset data for file: %s", filename);
+  }
+
+  // Close the file now we have the data
+  zip_fclose(file);
+
+  // Pass to the asset type loader
+  errorret_t ret = def->load(data, output);
+  memoryFree(data);
+  errorChain(ret);
   errorOk();
 }
 
 void assetDispose(void) {
-  if(ASSET_MANAGER.zip != NULL) {
-    zip_close(ASSET_MANAGER.zip);
-    ASSET_MANAGER.zip = NULL;
+  if(ASSET.zip != NULL) {
+    zip_close(ASSET.zip);
+    ASSET.zip = NULL;
   }
 }