#!/bin/sh

# This spell facilitates the setting of the configurations for thy Bitcoin system.

# Function to check if a command needs to be run with sudo
retry_with_sudo() {
    echo "Permission denied. Invoking the power of the super user..."
    sudo "$@"
    if [ $? -ne 0 ]; then
        echo "Failed to execute with elevated privileges. Make certain thou hast the necessary permissions and try again."
        exit 1
    fi
}

# Handle Ctrl-C
#trap "printf '\n'; exit 2" 2

# Create bitcoin directory and configuration file if they do not exist
mkdir -p "$HOME/.bitcoin"
touch "$HOME/.bitcoin/bitcoin.conf"

# Bitcoin defaults
defaults="proxy=127.0.0.1:9050
listen=1
bind=127.0.0.1
disablewallet=1
zmqpubrawblock=tcp://127.0.0.1:28332
zmqpubrawtx=tcp://127.0.0.1:28333"

bitcoin_conf="$HOME/.bitcoin/bitcoin.conf"

# If the file was just created (is empty), write defaults
if [ ! -s "$bitcoin_conf" ]; then
    echo "$defaults" > "$bitcoin_conf"
else
    ask_yn "Would you like to reset the bitcoin.conf file to defaults?" "n"
    reset_conf=$?
    if [ "$reset_conf" = 0 ]; then
        echo "$defaults" > "$bitcoin_conf"
    fi
fi

# Function to modify bitcoin.conf using awk
modify_bitcoin_conf() {
    local key=$1
    local value=$2
    printf "%s\n" >> "$bitcoin_conf" # Ensure a newline exists at the end of the file
    awk -v key="$key" -v value="$value" 'BEGIN {found=0} !/^#/ && $1==key {found=1; print key"="value; next} {print} END {if (!found) print key"="value}' "$bitcoin_conf" > "$bitcoin_conf.tmp" && mv "$bitcoin_conf.tmp" "$bitcoin_conf" || retry_with_sudo mv "$bitcoin_conf.tmp" "$bitcoin_conf"
    awk '/./' "$bitcoin_conf" > "$bitcoin_conf.tmp" && mv "$bitcoin_conf.tmp" "$bitcoin_conf" || retry_with_sudo mv "$bitcoin_conf.tmp" "$bitcoin_conf" # Remove trailing newlines
}

# Pruning question and storage amount
ask_yn "Wouldst thou like to enable pruning? Pruning allows thee to reduce disk usage by discarding some transaction history." "y"
prune=$?
if [ "$prune" = 0 ]; then
    modify_bitcoin_conf "prune" "1"
    valid_number=false
    while [ "$valid_number" = false ]; do
        printf "What is the maximum disk space thou art willing to dedicate to Bitcoin in GB? (Type a number) [default: 500]: "
        read -r max_disk

        if [ -z "$max_disk" ]; then
            max_disk=500
            valid_number=true
        elif validate_number "$max_disk"; then
            valid_number=true
        else
            printf "Invalid input. Please enter a valid number.\n"
        fi
    done

    # Convert GB to MB
    max_mem=$((max_disk * 1024))

    modify_bitcoin_conf "dbcache" "$max_mem"
else
    modify_bitcoin_conf "prune" "0"
fi

# Network selection
ask_yn "Art thou operating on the main Bitcoin network?" "y"
mainnet=$?
if [ "$mainnet" = 0 ]; then
    modify_bitcoin_conf "testnet" "0"
else
    modify_bitcoin_conf "testnet" "1"
fi

# Blockchain storage location
default_data_dir="$HOME/.bitcoin/blocks"
modify_bitcoin_conf "datadir" "$default_data_dir"
ask_yn "Wouldst thou like to store the blockchain in the default location ($default_data_dir)?" "y"
alt_storage=$?
if [ "$alt_storage" = 1 ]; then
	while true; do
    	printf "Please type the alternate path thou wouldst like to use for blockchain storage: "
	    read -r alt_path
	    if validate-path "$alt_path"; then
	    	break
		else
			printf "That's not a valid UNIX path string. "
		fi
	done
    modify_bitcoin_conf "datadir" "$alt_path"
fi

printf "Bitcoin configuration has been updated.\n"