ssh-agent-start.sh

#!/usr/bin/env bash
# ~/.local/bin/ssh-agent-start.sh

AGENT_ENV="$HOME/.ssh/agent.env"

agent_is_running() {
    [ "$SSH_AGENT_PID" ] && kill -0 "$SSH_AGENT_PID" 2>/dev/null
}

agent_has_keys() {
    ssh-add -l &>/dev/null
}

load_agent_env() {
    [ -f "$AGENT_ENV" ] && source "$AGENT_ENV" >| /dev/null
}

add_keys() {
    local keys=()
    shopt -s nullglob
    keys=(~/.ssh/*_rsa ~/.ssh/*_ecdsa ~/.ssh/*_ecdsa_sk ~/.ssh/*_ed25519 ~/.ssh/*_ed25519_sk ~/.ssh/*_dsa)
    shopt -u nullglob

    if [ ${#keys[@]} -gt 0 ]; then
        ssh-add "${keys[@]}"
    else
        echo "No keys found in ~/.ssh/"
    fi
}

start_agent() {
    echo "Starting new ssh-agent..."
    ssh-agent > "$AGENT_ENV"
    chmod 600 "$AGENT_ENV"
    source "$AGENT_ENV" >| /dev/null
    add_keys
}

load_agent_env

if agent_is_running; then
    if ! agent_has_keys; then
        echo "Agent running but no keys loaded, adding keys..."
        ssh-add
    else
        echo "Agent already running with keys loaded."
    fi
else
    start_agent
fi

#echo "SSH_AUTH_SOCK=$SSH_AUTH_SOCK"
#echo "SSH_AGENT_PID=$SSH_AGENT_PID"