1 files changed, 37 insertions, 0 deletions
diff --git a/save_file.lua b/save_file.lua
new file mode 100644
index 0000000..8dd85f2
--- /dev/null
+++ b/save_file.lua
@@ -0,0 +1,37 @@
+local util = require("util")
+
+local function save_file_write(filename, data)
+    os.rename(filename, filename..".bak")
+    local f = io.open(filename, "w")
+    if not f then
+        return false
+    end
+    f:write(util.json_enc(data))
+    f:close()
+    print("[save_file] saved to " .. filename)
+    return true
+end
+
+local function save_file_read(filename)
+    local data
+    local f = io.open(filename, "r")
+    if f then
+        data = util.json_dec(f:read("*all"))
+        f:close()
+        if not data then
+            return nil, "save_corrupted"
+        end
+        print("[save_file] loaded " .. filename)
+    else
+        data = {}
+    end
+    if not save_file_write(filename, data) then
+        return nil, "save_failed_write"
+    end
+    return data
+end
+
+return {
+    write = save_file_write,
+    read = save_file_read,
+}