#!/usr/bin/env bash

set -euo pipefail

require_ssh_key() {
	local key_path="$1"
	if [[ -z "$key_path" ]]; then
		echo "SSH key path is required" >&2
		return 1
	fi
	if [[ ! -f "$key_path" ]]; then
		echo "SSH key not found: $key_path" >&2
		return 1
	fi
}

ssh_common_opts() {
	local ssh_user="$1"
	local ssh_host="$2"

	# Keepalive to reduce flakiness through ProxyJump
	# (observed: "Connection reset by peer" during scp/ssh).
	#
	# Notes:
	# - Avoid SSH multiplexing here: ControlPath/ControlMaster can be flaky on Windows OpenSSH + MSYS paths.
	# - Increased timeouts and keepalive settings to handle network instability
	# - Compression disabled to reduce overhead and potential connection issues
	echo \
		-o BatchMode=yes \
		-o StrictHostKeyChecking=accept-new \
		-o ConnectTimeout=30 \
		-o ServerAliveInterval=10 \
		-o ServerAliveCountMax=6 \
		-o TCPKeepAlive=yes \
		-o Compression=no
}

ssh_run() {
	local ssh_key="$1"
	local ssh_user="$2"
	local ssh_host="$3"
	shift 3

	require_ssh_key "$ssh_key"

	local proxy_host="${DEPLOY_SSH_PROXY_HOST:-}"
	local proxy_user="${DEPLOY_SSH_PROXY_USER:-$ssh_user}"

	local proxy_args=()
	if [[ -n "$proxy_host" ]]; then
		proxy_args=(-J "$proxy_user@$proxy_host")
	fi

	# shellcheck disable=SC2207
	local common_opts=($(ssh_common_opts "$ssh_user" "$ssh_host"))

	ssh -i "$ssh_key" \
		"${common_opts[@]}" \
		"${proxy_args[@]}" \
		"$ssh_user@$ssh_host" "$@"
}

scp_copy() {
	local ssh_key="$1"
	local src="$2"
	local ssh_user="$3"
	local ssh_host="$4"
	local dst="$5"
	local recursive="${6:-false}"

	require_ssh_key "$ssh_key"

	local proxy_host="${DEPLOY_SSH_PROXY_HOST:-}"
	local proxy_user="${DEPLOY_SSH_PROXY_USER:-$ssh_user}"

	local proxy_args=()
	if [[ -n "$proxy_host" ]]; then
		proxy_args=(-o "ProxyJump=$proxy_user@$proxy_host")
	fi

	# shellcheck disable=SC2207
	local common_opts=($(ssh_common_opts "$ssh_user" "$ssh_host"))

	local scp_opts=()
	# Add -r for recursive copy if requested or if source is a directory
	if [[ "$recursive" == "true" ]] || [[ -d "$src" ]]; then
		scp_opts=(-r)
	fi

	scp -i "$ssh_key" \
		"${scp_opts[@]}" \
		"${common_opts[@]}" \
		"${proxy_args[@]}" \
		"$src" "$ssh_user@$ssh_host:$dst"
}