fix: stats crash (set -u + CSV header), header box, QR spacing

lib/stats.sh

@@ -85,16 +85,19 @@ EOF
     fi
 
     # Save snapshot for rate calculation (one per minute)
-    local minute_key=$(date +%s -d "1 minute ago" +%Y%m%d%H%M 2>/dev/null || date +%Y%m%d%H%M)
+    local minute_key
+    minute_key=$(date +%Y%m%d%H%M 2>/dev/null)
     local snapshot_file="$SNAPSHOTS_DIR/snap_${minute_key}.json"
     cp "$CURRENT_SNAPSHOT" "$snapshot_file" 2>/dev/null
 
     # Append to history CSV (once per minute, check if last entry is fresh)
     if [[ -f "$HISTORY_FILE" ]]; then
-        local last_ts=$(tail -1 "$HISTORY_FILE" 2>/dev/null | cut -d, -f1)
+        local last_ts
+        last_ts=$(grep -E '^[0-9]' "$HISTORY_FILE" 2>/dev/null | tail -1 | cut -d, -f1)
+        last_ts="${last_ts:-0}"
         local current_minute=$((ts - (ts % 60)))
 
-        if [[ -z "$last_ts" ]] || [[ $((current_minute - last_ts)) -ge 60 ]]; then
+        if [[ "$last_ts" -eq 0 ]] || [[ $((current_minute - last_ts)) -ge 60 ]]; then
             echo "$current_minute,$proxy_bytes,$site_bytes" >> "$HISTORY_FILE" 2>/dev/null
 
             # Cleanup old entries (keep only 365 days)
@@ -158,82 +161,61 @@ format_rate() {
     fi
 }
 
+# Safely convert value to integer (returns 0 for empty/non-numeric)
+_to_int() {
+    local val="${1:-0}"
+    # Strip non-numeric chars, default to 0
+    val="${val//[^0-9]/}"
+    echo "${val:-0}"
+}
+
+# Calculate diff safely (never negative, never crashes on empty)
+_safe_diff() {
+    local a=$(_to_int "$1")
+    local b=$(_to_int "$2")
+    local d=$((a - b))
+    (( d < 0 )) && d=0
+    echo "$d"
+}
+
 # Calculate traffic rates and totals from history
 stats_calculate_rates() {
     local traffic_type="$1"  # "proxy" or "site"
     local col_idx=2  # proxy_bytes is column 2
+    [[ "$traffic_type" == "site" ]] && col_idx=3
 
-    [[ "$traffic_type" == "site" ]] && col_idx=3  # site_bytes is column 3
+    local now
+    now=$(date +%s)
 
-    local now=$(date +%s)
-    local result=""
+    # Get latest data line (skip header with grep -E '^[0-9]')
+    local bytes_now
+    bytes_now=$(_to_int "$(grep -E '^[0-9]' "$HISTORY_FILE" 2>/dev/null | tail -1 | cut -d, -f"$col_idx")")
 
-    # 1 minute rate
-    local ts_1m=$((now - 60))
-    local bytes_now=$(tail -1 "$HISTORY_FILE" 2>/dev/null | cut -d, -f"$col_idx")
-    local bytes_1m=$(awk -F, -v ts="$ts_1m" '$1 >= ts' "$HISTORY_FILE" 2>/dev/null | head -1 | cut -d, -f"$col_idx")
-    local diff_1m=$((bytes_now - (bytes_1m > 0 ? bytes_1m : bytes_now)))
-    [[ $diff_1m -lt 0 ]] && diff_1m=0
-    local rate_1m=$((diff_1m / 60))
-    local bytes_1m_fmt=$(format_bytes "$diff_1m")
-    local rate_1m_fmt=$(format_rate "$rate_1m")
+    local periods="60 300 3600 86400 604800 2592000 31536000"
+    local results=""
 
-    # 5 minute rate
-    local ts_5m=$((now - 300))
-    local bytes_5m=$(awk -F, -v ts="$ts_5m" '$1 >= ts' "$HISTORY_FILE" 2>/dev/null | head -1 | cut -d, -f"$col_idx")
-    local diff_5m=$((bytes_now - (bytes_5m > 0 ? bytes_5m : bytes_now)))
-    [[ $diff_5m -lt 0 ]] && diff_5m=0
-    local rate_5m=$((diff_5m / 300))
-    local bytes_5m_fmt=$(format_bytes "$diff_5m")
-    local rate_5m_fmt=$(format_rate "$rate_5m")
+    for secs in $periods; do
+        local target_ts=$((now - secs))
+        # Find closest entry at or after target timestamp (skip header)
+        local old_val
+        old_val=$(_to_int "$(awk -F, -v ts="$target_ts" '$1 ~ /^[0-9]/ && $1 <= ts' "$HISTORY_FILE" 2>/dev/null | tail -1 | cut -d, -f"$col_idx")")
 
-    # 60 minute rate
-    local ts_60m=$((now - 3600))
-    local bytes_60m=$(awk -F, -v ts="$ts_60m" '$1 >= ts' "$HISTORY_FILE" 2>/dev/null | head -1 | cut -d, -f"$col_idx")
-    local diff_60m=$((bytes_now - (bytes_60m > 0 ? bytes_60m : bytes_now)))
-    [[ $diff_60m -lt 0 ]] && diff_60m=0
-    local rate_60m=$((diff_60m / 3600))
-    local bytes_60m_fmt=$(format_bytes "$diff_60m")
-    local rate_60m_fmt=$(format_rate "$rate_60m")
+        local diff
+        diff=$(_safe_diff "$bytes_now" "$old_val")
+        local rate=$(( secs > 0 ? diff / secs : 0 ))
 
-    # 1 day total
-    local ts_1d=$((now - 86400))
-    local bytes_1d=$(awk -F, -v ts="$ts_1d" '$1 >= ts' "$HISTORY_FILE" 2>/dev/null | head -1 | cut -d, -f"$col_idx")
-    local diff_1d=$((bytes_now - (bytes_1d > 0 ? bytes_1d : bytes_now)))
-    [[ $diff_1d -lt 0 ]] && diff_1d=0
-    local rate_1d=$((diff_1d > 0 ? diff_1d / 86400 : 0))
-    local bytes_1d_fmt=$(format_bytes "$diff_1d")
-    local rate_1d_fmt=$(format_rate "$rate_1d")
+        local bytes_fmt rate_fmt
+        bytes_fmt=$(format_bytes "$diff")
+        rate_fmt=$(format_rate "$rate")
 
-    # 7 days total
-    local ts_7d=$((now - 604800))
-    local bytes_7d=$(awk -F, -v ts="$ts_7d" '$1 >= ts' "$HISTORY_FILE" 2>/dev/null | head -1 | cut -d, -f"$col_idx")
-    local diff_7d=$((bytes_now - (bytes_7d > 0 ? bytes_7d : bytes_now)))
-    [[ $diff_7d -lt 0 ]] && diff_7d=0
-    local rate_7d=$((diff_7d > 0 ? diff_7d / 604800 : 0))
-    local bytes_7d_fmt=$(format_bytes "$diff_7d")
-    local rate_7d_fmt=$(format_rate "$rate_7d")
+        if [ -z "$results" ]; then
+            results="${bytes_fmt}|${rate_fmt}"
+        else
+            results="${results}|${bytes_fmt}|${rate_fmt}"
+        fi
+    done
 
-    # 30 days total
-    local ts_30d=$((now - 2592000))
-    local bytes_30d=$(awk -F, -v ts="$ts_30d" '$1 >= ts' "$HISTORY_FILE" 2>/dev/null | head -1 | cut -d, -f"$col_idx")
-    local diff_30d=$((bytes_now - (bytes_30d > 0 ? bytes_30d : bytes_now)))
-    [[ $diff_30d -lt 0 ]] && diff_30d=0
-    local rate_30d=$((diff_30d > 0 ? diff_30d / 2592000 : 0))
-    local bytes_30d_fmt=$(format_bytes "$diff_30d")
-    local rate_30d_fmt=$(format_rate "$rate_30d")
-
-    # 365 days total
-    local ts_365d=$((now - 31536000))
-    local bytes_365d=$(awk -F, -v ts="$ts_365d" '$1 >= ts' "$HISTORY_FILE" 2>/dev/null | head -1 | cut -d, -f"$col_idx")
-    local diff_365d=$((bytes_now - (bytes_365d > 0 ? bytes_365d : bytes_now)))
-    [[ $diff_365d -lt 0 ]] && diff_365d=0
-    local rate_365d=$((diff_365d > 0 ? diff_365d / 31536000 : 0))
-    local bytes_365d_fmt=$(format_bytes "$diff_365d")
-    local rate_365d_fmt=$(format_rate "$rate_365d")
-
-    # Return as pipe-delimited format for table display
-    echo "$bytes_1m_fmt|$rate_1m_fmt|$bytes_5m_fmt|$rate_5m_fmt|$bytes_60m_fmt|$rate_60m_fmt|$bytes_1d_fmt|$rate_1d_fmt|$bytes_7d_fmt|$rate_7d_fmt|$bytes_30d_fmt|$rate_30d_fmt|$bytes_365d_fmt|$rate_365d_fmt"
+    echo "$results"
 }
 
 # Main display function for traffic statistics