#!/bin/false

command -v recursive_dependencies >/dev/null ||
source dependencies.bash

# Input: $BASH_RPC_REMOTE_DEST - hostname passed to ssh (uses ssh host aliases)
# Input: $BASH_RPC_SSH_OPTIONS - option arguments passed to ssh (they precede '--')
# Input: "$0" - copied to remote bash's $0
# Input: $1 - shell script source code to run in the remote bash
# Input: $2, $3, ... - command line arguments passed to the remote bash as $1, $2, ...
# Input: stdin, stdout, stderr: passed to the remote bash over ssh
# Input: "$SHELL" - remote shell to launch (better be bash)
__bashrpc__remote_run_script()
{
        local script="$1"
        shift
        BASH_RPC_SHELL_OPTIONS=(--norc --noprofile)
        # printf 'DEBUG:<%s>\n' "${BASH_RPC_SSH_OPTIONS[@]}" >&2
        exec ssh \
                "${BASH_RPC_SSH_OPTIONS[@]}" -- \
                "${BASH_RPC_REMOTE_DEST:-localhost}" \
                "$SHELL" "${BASH_RPC_SHELL_OPTIONS[@]}" \
                -c "${script@Q}" \
                "$0" "${@@Q}"
}

with_ssh_options() { __bashrpc__with_ssh_options "$@"; }
__bashrpc__with_ssh_options()
{
        local -a BASH_RPC_SSH_OPTIONS
        while [ "$1" != '--' ]
        do
                if [ $# -gt 0 ]
                then
                        BASH_RPC_SSH_OPTIONS+=("$1")
                        shift
                        continue
                fi
                >&2 printf '%s: Error: %s\n' "$0" \
'with_ssh_options(): expected argument "--" not found'
                exit 1
        done
        shift
        "$@"
}

with_ssh_option() { __bashrpc__with_ssh_option "$@"; }
__bashrpc__with_ssh_option()
{
        local -a BASH_RPC_SSH_OPTIONS=("${BASH_RPC_SSH_OPTIONS[@]}")
        BASH_RPC_SSH_OPTIONS+=("$1")
        shift
        "$@"
}

# Preserves the rest of stdin for the command.
__bashrpc__eval_stdin()
{
        [ "$1" ] && read -N"$1" -r || return

        # Prepare "$@" for script execution context.
        shift

        # Even unset REPLY to leave pristine environment.
        eval "unset REPLY; $REPLY"
}

__bashrpc__run_function_simple()
{
        script_source=$(declare -f "$1" && printf '"$@";\n')
        __bashrpc__remote_run_script  \
                "$script_source" \
                "$@"
}

__bashrpc__notty_stage1()
{
        [ "$1" ] &&
        read -N"$1" -r && # Read script from stdin, munges REPLY
        shift && # Prepare "$@" for script execution context.
        eval "unset REPLY; $REPLY" # Unset munged REPLY in exec context
}

__bashrpc__remote_run_stage1_notty()
{
        stage1_source=$(
                declare -f __bashrpc__notty_stage1 |
                        sed -Ene 's/^ {4}//p'
        )
        stage2_source=$1
        shift
        {
                printf '%s' "$stage2_source"
                cat
        } |
                __bashrpc__remote_run_script \
                        "$stage1_source" "${#stage2_source}" \
                        "$@"
}

__bashrpc__read_stdin()
{
        REPLY=
        read -r -N2147483647 || [ "$REPLY" ]
}

__bashrpc__tty_stage1()
{
        local SET_TERM="$1"
        local PRELUDE="shift;${BASH_RPC_TRACE_REMOTE:+ set -x;}"
        __bashrpc__read_stdin <<END
# We saved stage2 in TERM.
# Store it in parameter 1:
set -- "\$TERM" "\$@"
# Restore original TERM:
TERM=${SET_TERM@Q}
# Run stage2:
source <(printf '%s\n%s' ${PRELUDE@Q} "\$1")
END
        printf '%s' "$REPLY"
}

__bashrpc__remote_run_stage1_tty()
{
        stage2_source=$1
        stage1_source=$(__bashrpc__tty_stage1 "$TERM" | grep -v '^#')
        shift
        (
                # printf 'DEBUG2:<%s>\n' "${BASH_RPC_SSH_OPTIONS[@]}" >&2
                TERM="$stage2_source" \
                        __bashrpc__with_ssh_option -t \
                        __bashrpc__remote_run_script \
                        "$stage1_source" "$@"
        )
}

remote_run_function()
{
        main=$1
        # funcs=$(compgen -A function)
        funcs=$(recursive_dependencies "$main")
        stage2_source=$(
                declare -f $funcs
                printf '"$@"\n'
        )
        if [ -t 0 ]
        then
                __bashrpc__remote_run_stage1_tty "$stage2_source" "$@"
        else
                __bashrpc__remote_run_stage1_notty "$stage2_source" "$@"
        fi
}