#!/bin/bash

###
##
## Looks for a string that shows a post was found for a search listing.
## When found, alert emails are sent.
##
###

# Define parameters
URL="https://www.dfl.de/de/?s=Sicherheitskontext&submit="
SEARCH_STRING='Teilnehmende schließen Zertifikatsstudium';
RECIPIENTS=("r.hellyer@syde.com" "ryanhellyer@gmail.com")
SUBJECT="DFL search down"
BODY="Alert: The DFL search system is currently down."

# Set absolute path to msmtp config
export MSMTPRC="/etc/msmtprc"

# Create log directory if it doesn't exist
LOG_DIR="/var/log/msmtp"
[ ! -d "$LOG_DIR" ] && sudo mkdir -p "$LOG_DIR" && sudo chmod 777 "$LOG_DIR"

# Fetch the webpage and check for the string
if ! webpage_content=$(curl -s "$URL"); then
    echo "Failed to fetch webpage" >> "$LOG_DIR/dfl-check.log"
    exit 1
fi

echo $webpage_content > "$LOG_DIR/dfl.html"

# Check if the string exists in the webpage content
if echo "$webpage_content" | grep -q "$SEARCH_STRING"; then
    echo "$(date): Search string found - system working normally" >> "$LOG_DIR/dfl-check.log"
    exit 0
else
    echo "$(date): Search string NOT found - sending alert" >> "$LOG_DIR/dfl-check.log"
    # String not found - send alert email
    if command -v msmtp >/dev/null 2>&1; then
        for recipient in "${RECIPIENTS[@]}"; do
            {
                echo "To: $recipient"
                echo "Subject: $SUBJECT"
                echo "Content-Type: text/plain"
                echo
                echo "$BODY"
                echo "Time: $(date)"
            } | msmtp --file=/etc/msmtprc "$recipient" 2>> "$LOG_DIR/dfl-check.log"
            
            if [ $? -eq 0 ]; then
                echo "$(date): Alert email sent successfully to $recipient" >> "$LOG_DIR/dfl-check.log"
            else
                echo "$(date): Failed to send alert email to $recipient" >> "$LOG_DIR/dfl-check.log"
                exit 1
            fi
        done
        exit 0
    else
        echo "$(date): Error: msmtp not found" >> "$LOG_DIR/dfl-check.log"
        exit 1
    fi
fi