#!/bin/bash
# System Health Report - Sends daily summary to Discord
# Usage: ./health-report.sh [--errors-only]

WEBHOOK_URL="${DISCORD_WEBHOOK_URL:-YOUR_WEBHOOK_URL_HERE}"
DATA_DIR="$HOME/.local/share/health-monitor"
ERRORS_ONLY="${1:-}"

# Colors for Discord embeds
COLOR_OK=3066993      # Green
COLOR_WARN=16776960   # Yellow
COLOR_ERROR=15158332  # Red

# Thresholds
DISK_WARN=80
DISK_CRIT=90
MEM_WARN=80
MEM_CRIT=90

# Gather basic info
HOSTNAME=$(hostname)
UPTIME=$(uptime -p | sed 's/up //')

# Calculate stats from collected data (today + yesterday for context)
YESTERDAY=$(date -d "yesterday" +%Y-%m-%d 2>/dev/null || date -v-1d +%Y-%m-%d 2>/dev/null)
TODAY=$(date +%Y-%m-%d)

# Combine recent data files
STATS_DATA=""
for f in "$DATA_DIR/stats-$YESTERDAY.csv" "$DATA_DIR/stats-$TODAY.csv"; do
    [ -f "$f" ] && STATS_DATA+=$(tail -n +2 "$f")$'\n'
done

# Calculate min/avg/max if we have data
if [ -n "$STATS_DATA" ] && [ $(echo "$STATS_DATA" | grep -c .) -gt 0 ]; then
    CPU_STATS=$(echo "$STATS_DATA" | awk -F',' 'NF>=2 && $2~/^[0-9]/ {sum+=$2; if(min=="" || $2<min)min=$2; if($2>max)max=$2; n++} END {if(n>0) printf "%.0f / %.0f / %.0f", min, sum/n, max; else print "N/A"}')
    MEM_STATS=$(echo "$STATS_DATA" | awk -F',' 'NF>=3 && $3~/^[0-9]/ {sum+=$3; if(min=="" || $3<min)min=$3; if($3>max)max=$3; n++} END {if(n>0) printf "%.0f / %.0f / %.0f", min, sum/n, max; else print "N/A"}')
    LOAD_STATS=$(echo "$STATS_DATA" | awk -F',' 'NF>=4 && $4~/^[0-9]/ {sum+=$4; if(min=="" || $4<min)min=$4; if($4>max)max=$4; n++} END {if(n>0) printf "%.2f / %.2f / %.2f", min, sum/n, max; else print "N/A"}')
    SAMPLES=$(echo "$STATS_DATA" | grep -c .)

    # Get max values for threshold checks
    MEM_MAX=$(echo "$STATS_DATA" | awk -F',' 'NF>=3 && $3~/^[0-9]/ {if($3>max)max=$3} END {print int(max)}')
    [ -z "$MEM_MAX" ] && MEM_MAX=0
else
    CPU_STATS="No data yet"
    MEM_STATS="No data yet"
    LOAD_STATS="No data yet"
    SAMPLES=0
    MEM_MAX=0
fi

# Current disk usage
DISK_PCT=$(df / | awk 'NR==2 {gsub(/%/,""); print $5}')
DISK_DETAIL=$(df -h / | awk 'NR==2 {printf "%s / %s", $3, $2}')

# SSD SMART status
SMART_STATUS="Unknown"
if command -v smartctl &>/dev/null; then
    SMART_OUT=$(smartctl -H /dev/sda 2>&1)
    if echo "$SMART_OUT" | grep -q "PASSED"; then
        SMART_STATUS="PASSED ✓"
    elif echo "$SMART_OUT" | grep -q "FAILED"; then
        SMART_STATUS="FAILED ✗"
    elif echo "$SMART_OUT" | grep -qi "permission"; then
        SMART_STATUS="Needs root"
    fi
fi

# Recent errors from journal (last 24h)
ERRORS=""
if command -v journalctl &>/dev/null; then
    ERRORS=$(journalctl -p err -S "24 hours ago" --no-pager -q 2>/dev/null | tail -10)
fi
ERROR_COUNT=$(echo "$ERRORS" | grep -c . 2>/dev/null || echo 0)
[ -z "$ERRORS" ] && ERROR_COUNT=0

# Determine overall status
STATUS="OK"
COLOR=$COLOR_OK

if [ "$DISK_PCT" -ge "$DISK_CRIT" ] || [ "$MEM_MAX" -ge "$MEM_CRIT" ]; then
    STATUS="CRITICAL"
    COLOR=$COLOR_ERROR
elif [ "$DISK_PCT" -ge "$DISK_WARN" ] || [ "$MEM_MAX" -ge "$MEM_WARN" ] || [ "$ERROR_COUNT" -gt 0 ]; then
    STATUS="WARNING"
    COLOR=$COLOR_WARN
fi

if echo "$SMART_STATUS" | grep -q "FAILED"; then
    STATUS="CRITICAL"
    COLOR=$COLOR_ERROR
fi

# Skip if errors-only mode and everything is OK
if [ "$ERRORS_ONLY" = "--errors-only" ] && [ "$STATUS" = "OK" ]; then
    exit 0
fi

# Format errors for Discord
ERROR_FIELD=""
if [ "$ERROR_COUNT" -gt 0 ] && [ -n "$ERRORS" ]; then
    # Escape and truncate errors
    ERRORS_CLEAN=$(echo "$ERRORS" | head -5 | sed 's/`/'"'"'/g' | tr '\n' '|' | sed 's/|/\\n/g' | cut -c1-400)
    ERROR_FIELD=',{"name": "📋 Recent Errors", "value": "```'"$ERRORS_CLEAN"'```", "inline": false}'
fi

# Build Discord embed JSON
PAYLOAD=$(cat <<EOF
{
  "embeds": [{
    "title": "🖥️ ${HOSTNAME} - Health Report",
    "color": ${COLOR},
    "fields": [
      {"name": "Status", "value": "**${STATUS}**", "inline": true},
      {"name": "Uptime", "value": "${UPTIME}", "inline": true},
      {"name": "Samples", "value": "${SAMPLES} (24h)", "inline": true},
      {"name": "💻 CPU % (min/avg/max)", "value": "${CPU_STATS}", "inline": true},
      {"name": "🧠 RAM % (min/avg/max)", "value": "${MEM_STATS}", "inline": true},
      {"name": "📊 Load (min/avg/max)", "value": "${LOAD_STATS}", "inline": true},
      {"name": "💾 Disk /", "value": "${DISK_PCT}% (${DISK_DETAIL})", "inline": true},
      {"name": "🔧 SSD Health", "value": "${SMART_STATUS}", "inline": true},
      {"name": "⚠️ Errors (24h)", "value": "${ERROR_COUNT}", "inline": true}${ERROR_FIELD}
    ],
    "footer": {"text": "$(date '+%Y-%m-%d %H:%M:%S')"}
  }]
}
EOF
)

# Send to Discord
RESPONSE=$(curl -s -o /dev/null -w "%{http_code}" -H "Content-Type: application/json" -d "$PAYLOAD" "$WEBHOOK_URL")

if [ "$RESPONSE" = "204" ]; then
    echo "Health report sent successfully"
else
    echo "Failed to send report (HTTP $RESPONSE)"
    echo "$PAYLOAD" | head -50
    exit 1
fi