1 files changed, 117 insertions, 0 deletions
diff --git a/asset.c b/asset.c
new file mode 100644
index 0000000..e6aafe5
--- /dev/null
+++ b/asset.c
@@ -0,0 +1,117 @@
+#include <stdio.h>
+
+#include "asset.h"
+#include "error.h"
+#include "platform.h"
+#include "standard.h"
+
+static const char* const asset_vpaths[] = {
+	/* asset_id_usr */ "data/usr.img"
+};
+
+static struct {
+	FILE* pack;
+	int pack_count;
+
+	unsigned char memory[asset_memory];
+	int memory_ptr;
+
+	Bitmap bitmaps[bitmap_asset_count];
+	int bitmap_count;
+} asset_manager;
+
+void* asset_mgr_alloc(int size) {
+	void* a;
+
+	a = &asset_manager.memory[asset_manager.memory_ptr];
+	asset_manager.memory_ptr += size;
+
+#ifdef DEBUG
+	if (asset_manager.memory_ptr > asset_memory) {
+		platform_err("Out of asset memory.\n");
+		platform_abort(error_out_of_memory);
+	}
+#endif
+
+	return a;
+}
+
+/* Loading assets isn't that efficient. Too bad. */
+int get_asset_info(const char* name, int* offset, int* size) {
+	int head_size = 8, i;
+	char buf[56];
+
+	fseek(asset_manager.pack, head_size, SEEK_SET);
+
+	for (i = 0; i < asset_manager.pack_count; i++) {
+		fread(size,   4, 1,          asset_manager.pack);
+		fread(offset, 4, 1,          asset_manager.pack);
+		fread(buf,    1, sizeof buf, asset_manager.pack);
+
+		if (string_equal(buf, name)) {
+			return 1;
+		}
+	}
+
+	return 0;
+}
+
+void load_assets() {
+	int i, offset, size;
+	const char* name;
+	Bitmap* bmp;
+	FILE* pack;
+	char magic[4];
+
+	asset_manager.bitmap_count = 0;
+
+	pack = fopen("pack", "rb");
+	if (!pack) {
+		platform_err("Failed to open 'pack'. Did you delete it?");
+		platform_abort(error_file_not_found);
+	}
+
+	asset_manager.pack = pack;
+
+	fread(&asset_manager.pack_count, 4, 1, pack);
+
+#define gi(e_) \
+		name = asset_vpaths[i]; \
+		if (get_asset_info(name, &offset, &size)) { \
+			fseek(pack, offset, SEEK_SET); \
+			e_ \
+		} else { \
+			platform_err( \
+				"%s doesn't exist in the pack. " \
+				"Is the pack corrupt?\n", \
+				name \
+			); \
+			platform_abort(error_file_not_found); \
+		}
+
+	for (i = 0; i < bitmap_asset_count; i++) {
+		gi({
+			bmp = &asset_manager.bitmaps[asset_manager.bitmap_count++];
+			fread(magic,   4, 1, pack);
+
+			if (!string_equal(magic, "IMAG")) {
+				platform_err("Invalid asset\n");
+				platform_abort(error_invalid_asset);
+			}
+
+			fread(&bmp->w, 4, 1, pack);
+			fread(&bmp->h, 4, 1, pack);
+			size = bmp->w * bmp->h * sizeof *bmp->pixels;
+			bmp->pixels = asset_mgr_alloc(size);
+			fread(bmp->pixels, 1, size, pack);
+		});
+	}
+
+#undef gi
+
+	fclose(pack);
+}
+
+const Bitmap* get_bitmap(Asset_ID id) {
+	return &asset_manager.bitmaps[id];
+}