fix: 优化 README 内容问题，优化绘图

services/statistics.py

@@ -9,7 +9,7 @@ async def get_ammeter_left_ele(limit=24):
         conn.row_factory = aiosqlite.Row
         cursor = await conn.execute(
             """
-            SELECT created_at, left_ele
+            SELECT created_at, left_ele, left_free_ele
             FROM ammeter_usage
             ORDER BY created_at DESC
             LIMIT ?
@@ -20,10 +20,13 @@ async def get_ammeter_left_ele(limit=24):
 
     rows.reverse()
 
-    times = [time.strftime("%H:%M", time.localtime(r[0] / 1000)) for r in rows]
-    values = [r[1] for r in rows]
+    times = [r[0] for r in rows]
+    # times = [time.strftime("%H:%M", time.localtime(r[0] / 1000)) for r in rows]
+    
+    left_ele = [r[1] for r in rows]
+    left_free_ele = [r[2] for r in rows]
 
-    return times, values
+    return times, left_ele, left_free_ele
 
 
 async def get_water_left(limit=24):
@@ -31,7 +34,7 @@ async def get_water_left(limit=24):
         conn.row_factory = aiosqlite.Row
         cursor = await conn.execute(
             """
-            SELECT created_at, left_water
+            SELECT created_at, left_water, left_free_water
             FROM water_usage
             ORDER BY created_at DESC
             LIMIT ?
@@ -42,7 +45,10 @@ async def get_water_left(limit=24):
 
     rows.reverse()
 
-    times = [time.strftime("%H:%M", time.localtime(r[0] / 1000)) for r in rows]
-    values = [r[1] for r in rows]
+    times = [r[0] for r in rows]
+    # times = [time.strftime("%Y-%m-%d %H:%M", time.localtime(r[0] / 1000)) for r in rows]
 
-    return times, values
+    left_water = [r[1] for r in rows]
+    left_free_water = [r[2] for r in rows]
+
+    return times, left_water, left_free_water