Update src/streamlit_app.py

src/streamlit_app.py

@@ -1,8 +1,10 @@
 import streamlit as st
 import pandas as pd
-import math
 import plotly.graph_objects as go
 import plotly.express as px
+import json
+import os
+from datetime import datetime
 
 # 页面配置（必须在最开始）
 st.set_page_config(
@@ -12,6 +14,53 @@ st.set_page_config(
     initial_sidebar_state="expanded"
 )
 
+# 访问统计功能
+def manage_visit_stats():
+    """管理访问统计"""
+    stats_file = "visit_stats.json"
+    
+    # 初始化统计数据
+    if os.path.exists(stats_file):
+        try:
+            with open(stats_file, 'r', encoding='utf-8') as f:
+                stats = json.load(f)
+        except:
+            stats = {
+                "total_visits": 0,
+                "daily_visits": {},
+                "first_visit": datetime.now().strftime("%Y-%m-%d %H:%M:%S"),
+                "last_visit": None
+            }
+    else:
+        stats = {
+            "total_visits": 0,
+            "daily_visits": {},
+            "first_visit": datetime.now().strftime("%Y-%m-%d %H:%M:%S"),
+            "last_visit": None
+        }
+    
+    # 检查是否需要更新统计
+    if 'visit_counted' not in st.session_state:
+        st.session_state.visit_counted = True
+        
+        # 更新统计
+        today = datetime.now().strftime("%Y-%m-%d")
+        stats["total_visits"] += 1
+        stats["daily_visits"][today] = stats["daily_visits"].get(today, 0) + 1
+        stats["last_visit"] = datetime.now().strftime("%Y-%m-%d %H:%M:%S")
+        
+        # 保存统计
+        try:
+            with open(stats_file, 'w', encoding='utf-8') as f:
+                json.dump(stats, f, ensure_ascii=False, indent=2)
+        except:
+            pass  # 忽略写入错误
+    
+    return stats
+
+# 在页面配置后调用
+visit_stats = manage_visit_stats()
+
 # 自定义CSS样式
 st.markdown("""
 <style>
@@ -75,6 +124,16 @@ st.markdown("""
         overflow: hidden;
         box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
     }
+    
+    /* 访问统计样式 */
+    .visit-stats {
+        background: linear-gradient(135deg, #00b894 0%, #00a085 100%);
+        color: white;
+        padding: 1rem;
+        border-radius: 10px;
+        margin: 1rem 0;
+        text-align: center;
+    }
 </style>
 """, unsafe_allow_html=True)
 
@@ -129,7 +188,15 @@ LANGUAGES = {
         "instruction_4": "4. **查看结果**: 右侧显示转换结果和详细信息",
         "note": "⚠️ **注意**: 本计算假设理想混合，实际情况可能存在偏差。",
         "language": "🌐 语言",
-        "visualization": "📈 可视化"
+        "visualization": "📈 可视化",
+        "visit_stats": "📊 访问统计",
+        "total_visits": "总访问量",
+        "today_visits": "今日访问",
+        "last_visit": "上次访问",
+        "visit_trend": "访问趋势",
+        "recent_days": "最近访问趋势",
+        "date": "日期",
+        "visits": "访问次数"
     },
     "English": {
         "page_title": "Solvent Fraction Converter",
@@ -180,7 +247,15 @@ LANGUAGES = {
         "instruction_4": "4. **View Results**: Results and detailed information are displayed on the right",
         "note": "⚠️ **Note**: This calculation assumes ideal mixing; actual situations may deviate.",
         "language": "🌐 Language",
-        "visualization": "📈 Visualization"
+        "visualization": "📈 Visualization",
+        "visit_stats": "📊 Visit Statistics",
+        "total_visits": "Total Visits",
+        "today_visits": "Today's Visits",
+        "last_visit": "Last Visit",
+        "visit_trend": "Visit Trend",
+        "recent_days": "Recent Visit Trend",
+        "date": "Date",
+        "visits": "Visits"
     }
 }
 
@@ -298,6 +373,52 @@ with st.sidebar:
         rho_b = current_solvents[solvent_b_name]["density"]
         st.info(f"📊 {lang['molar_mass']}: **{M_b}** g/mol  \n📊 {lang['density']}: **{rho_b}** g/cm³")
 
+    # 访问统计显示
+    st.markdown("---")
+    st.markdown("### " + lang["visit_stats"])
+    
+    # 显示统计信息
+    col1, col2 = st.columns(2)
+    with col1:
+        st.metric(lang["total_visits"], visit_stats["total_visits"])
+    with col2:
+        today = datetime.now().strftime("%Y-%m-%d")
+        today_visits = visit_stats["daily_visits"].get(today, 0)
+        st.metric(lang["today_visits"], today_visits)
+    
+    # 显示最近访问时间
+    if visit_stats["last_visit"]:
+        st.caption(f"{lang['last_visit']}: {visit_stats['last_visit']}")
+    
+    # 显示访问趋势（简单的条形图）
+    if len(visit_stats["daily_visits"]) > 1:
+        recent_days = list(visit_stats["daily_visits"].items())[-7:]  # 最近7天
+        dates = [item[0] for item in recent_days]
+        counts = [item[1] for item in recent_days]
+        
+        if len(dates) > 1:
+            df_visits = pd.DataFrame({
+                lang["date"]: dates,
+                lang["visits"]: counts
+            })
+            fig_visits = px.bar(
+                df_visits, 
+                x=lang["date"], 
+                y=lang["visits"], 
+                title=lang["recent_days"],
+                height=200,
+                color=lang["visits"],
+                color_continuous_scale="viridis"
+            )
+            fig_visits.update_layout(
+                showlegend=False,
+                margin=dict(l=20, r=20, t=40, b=20),
+                xaxis_title="",
+                yaxis_title="",
+                font=dict(size=10)
+            )
+            st.plotly_chart(fig_visits, use_container_width=True)
+
 # 主界面内容
 col1, col2 = st.columns([1, 1], gap="large")