#!/bin/bash

# Combined installation script for Proxmox task history size modification
# This script installs both the update logic and the cron job

set -euo pipefail  # Exit on error, undefined vars, pipe failures

# Colors for output
RED='\033[0;31m'
GREEN='\033[0;32m'
YELLOW='\033[1;33m'
NC='\033[0m' # No Color

# Error handling function
error_exit() {
    echo -e "${RED}ERROR: $1${NC}" >&2
    exit 1
}

# Success message function
success_msg() {
    echo -e "${GREEN}✓${NC} $1"
}

# Warning message function
warning_msg() {
    echo -e "${YELLOW}⚠${NC} $1"
}

# Check if running as root
if [[ $EUID -ne 0 ]]; then
    error_exit "This script must be run as root (use sudo)"
fi

# Check if Proxmox is installed
if [[ ! -f "/usr/share/perl5/PVE/RESTEnvironment.pm" ]]; then
    warning_msg "Proxmox VE may not be installed (RESTEnvironment.pm not found)"
    warning_msg "The script will still be installed, but it may not work until Proxmox is installed"
fi

echo "Installing Proxmox task history size modification..."

# ============================================================================
# Part 1: Install the update logic script
# ============================================================================

# Create parent directory if it does not exist
if ! mkdir -p /etc/cronscripts/change_pve_task_history_size; then
    error_exit "Failed to create directory /etc/cronscripts/change_pve_task_history_size"
fi

# Path to the target script
TARGET_SCRIPT="/etc/cronscripts/change_pve_task_history_size/update_pve_max_task_history_size.sh"

# Backup existing script if it exists
if [[ -f "$TARGET_SCRIPT" ]]; then
    BACKUP_SCRIPT="${TARGET_SCRIPT}.backup.$(date +%Y%m%d_%H%M%S)"
    if cp "$TARGET_SCRIPT" "$BACKUP_SCRIPT"; then
        warning_msg "Existing script backed up to: $BACKUP_SCRIPT"
    else
        error_exit "Failed to backup existing script"
    fi
fi

# Write the script contents
if ! cat << 'EOF' > "$TARGET_SCRIPT"
#!/bin/bash

# /etc/cronscripts/change_pve_task_history_size/update_pve_max_task_history_size.sh

# Path to the RESTEnvironment.pm file
FILE="/usr/share/perl5/PVE/RESTEnvironment.pm"

# Search and replacement strings
SEARCH="my \$maxsize = 50000; # about 1000 entries"
REPLACE="my \$maxsize = 1000000; # about 20000 entries, around 1 year task history"

# Check if the file exists
if [[ -f "$FILE" ]]; then
    # Check if the target string exists in the file
    if grep -qF "$SEARCH" "$FILE"; then
        logger -t change_pve_task_history_size "String found in $FILE. Replacing '$SEARCH' with '$REPLACE'."
       
        # Create a backup of the file
        BACKUP_FILE="$FILE.$(date +%Y%m%d_%H%M%S)"
        cp "$FILE" "$BACKUP_FILE"
        logger -t change_pve_task_history_size "Backup created: $BACKUP_FILE"
       
        # Replace the target string in the file
        sed -i "s|$SEARCH|$REPLACE|" "$FILE"
        logger -t change_pve_task_history_size "String replaced successfully in $FILE."
       
        # Restart Proxmox services
        systemctl restart pvedaemon.service pveproxy.service
        logger -t change_pve_task_history_size "Services restarted."
    else
        logger -t change_pve_task_history_size "Search string not found in $FILE. No changes made."
    fi
else
    logger -t change_pve_task_history_size "File $FILE does not exist!"
fi
EOF
then
    error_exit "Failed to write script to $TARGET_SCRIPT"
fi

# Make script executable
if ! chmod +x "$TARGET_SCRIPT"; then
    error_exit "Failed to make script executable"
fi

# Verify script was created and is executable
if [[ ! -f "$TARGET_SCRIPT" ]] || [[ ! -x "$TARGET_SCRIPT" ]]; then
    error_exit "Script verification failed: $TARGET_SCRIPT"
fi

success_msg "Update script created at $TARGET_SCRIPT"

# ============================================================================
# Part 2: Install the cron job
# ============================================================================

# Ensure parent directory exists
if ! mkdir -p /etc/cron.d; then
    error_exit "Failed to create directory /etc/cron.d"
fi

# Target cron file
TARGET_CRON="/etc/cron.d/change_pve_task_history_size"

# Backup existing cron file if it exists
if [[ -f "$TARGET_CRON" ]]; then
    BACKUP_CRON="${TARGET_CRON}.backup.$(date +%Y%m%d_%H%M%S)"
    if cp "$TARGET_CRON" "$BACKUP_CRON"; then
        warning_msg "Existing cron file backed up to: $BACKUP_CRON"
    else
        error_exit "Failed to backup existing cron file"
    fi
fi

# Write cron contents
if ! cat << 'EOF' > "$TARGET_CRON"
# Cron job for updating Proxmox task history size

# /etc/cron.d/change_pve_task_history_size

@reboot root /etc/cronscripts/change_pve_task_history_size/update_pve_max_task_history_size.sh
0 * * * * root /etc/cronscripts/change_pve_task_history_size/update_pve_max_task_history_size.sh
EOF
then
    error_exit "Failed to write cron file to $TARGET_CRON"
fi

# Correct permissions for cron.d files
if ! chmod 644 "$TARGET_CRON"; then
    error_exit "Failed to set permissions on cron file"
fi

# Verify cron file was created
if [[ ! -f "$TARGET_CRON" ]]; then
    error_exit "Cron file verification failed: $TARGET_CRON"
fi

success_msg "Cron file created at $TARGET_CRON"

# ============================================================================
# Installation complete
# ============================================================================

echo ""
echo -e "${GREEN}Installation complete!${NC}"
echo "  - Update script: $TARGET_SCRIPT"
echo "  - Cron job: $TARGET_CRON"
echo ""
echo "The script will run on system reboot and every hour."
echo ""
echo "To verify installation, check the logs with:"
echo "  journalctl -t change_pve_task_history_size"