#!/bin/bash

#########################################################
# Options                                               #
#########################################################

set -e
set -o pipefail

#########################################################
# Globals                                               #
#########################################################

readonly GITLAB_URI="https://git.pleroma.social"
readonly PREFIX_API="api/v4/projects/pleroma%2Fpleroma/repository"
readonly ENDPOINT_FILE="pleroma/pleroma/raw"
readonly ENDPOINT_LIST="pleroma/pleroma/files"
readonly ENDPOINT_TAG="$PREFIX_API/tags"
readonly ENDPOINT_BLOB="$PREFIX_API/blobs"
readonly ENDPOINT_BRANCH="$PREFIX_API/branches"

flags=""

#########################################################
# Helpers                                               #
#########################################################

has_command() {
    if command -v 1>/dev/null 2>&1 "$1"; then
        return 0
    else
        return 1
    fi
}

require_command() {
    if ! has_command "$1"; then
        printf "\nError: This action requires the command '%s' in your PATH.\n" "$1"
        exit 1
    fi
}

require_file() {
    if [[ ! -f $1 ]]; then
        echo "File missing: '$1' (Example at: '$2')"
        FILE_FAILED=1
    fi
}

throw_file_errors() {
    if [[ -n "$FILE_FAILED" ]]; then
        echo ""
        echo "Please create the missing files first."
        echo "The script will now exit."
        exit 1
    fi
}

render_template() {
    require_command m4
    require_command awk

    m4 $flags docker-compose.m4 | awk 'NF'
}

docker_compose() {
    require_command docker-compose

    docker-compose \
        -f <(render_template) \
        --project-directory . \
        "$@"
}

load_env() {
    while read -r line; do
        if [[ "$line" == \#* ]] || [[ -z "$line" ]]; then
            continue;
        fi

        export "${line?}"
        flags="-D__${line?} $flags"
    done < .env
}

download_file() { # $1: source, $2: target
    if has_command curl; then
        curl -sSL "$1" -o "$2"
    elif has_command wget; then
        wget "$1" -O "$2"
    else
        printf "\nError: This action requires either curl or wget in your PATH.\n"
        exit 1
    fi
}

request_file_content() { # $1: source
    if has_command curl; then
        curl -sSL "$1"
    elif has_command wget; then
        wget "$1" -O- 2>/dev/null
    else
        printf "\nError: This action requires either curl or wget in your PATH.\n"
        exit 1
    fi
}

#########################################################
# Subcommands                                           #
#########################################################

action__build() {
    docker_compose build --build-arg __BUST_CACHE="$(date +%s)" server
}

action__dump() {
    cat <(render_template)
}

action__enter() {
    docker_compose exec server sh -c 'cd ~/pleroma && bash'
}

action__logs() {
    docker_compose logs "$@"
}

action__mix() {
    docker_compose exec server sh -c "cd ~/pleroma && mix $*"
}

action__passthrough() {
    docker_compose "$@"
}

action__p() {
    action__passthrough "$@"
}

action__restart() {
    action__stop
    action__start
}

action__start() {
    docker_compose up --remove-orphans -d
}

action__up() {
    action__start
}

action__stop() {
    docker_compose down
}

action__down() {
    action__stop
}

action__status() {
    docker_compose ps
}

action__ps() {
    action__status
}

action__debug() {
    require_command xhost

    local debug_mounts
    debug_mounts="
        -v $(pwd)/custom.d:/custom.d \
        -v $(pwd)/debug.d/build:/home/pleroma/pleroma/_build \
        -v $(pwd)/debug.d/deps:/home/pleroma/pleroma/deps \
    "

    if [[ ! -d ./debug.d ]]; then
        mkdir -p ./debug.d/{build,deps}
    fi

    if [[ ! -d ./custom.d/lib ]]; then
        mkdir -p ./custom.d/lib
    fi

    action__stop

    docker_compose run --rm -u pleroma -w /home/pleroma/pleroma "$debug_mounts" server bash -c 'cp -rvf /custom.d/* /home/pleroma/pleroma && mix deps.get'

    local x_flags=""
    if [[ $NO_X_FORWARDING != 1 ]]; then
        x_flags="-e DISPLAY=$DISPLAY -v /tmp/.X11-unix:/tmp/.X11-unix"
    fi

    [[ $NO_X_FORWARDING == 1 ]] || xhost +local:root
    docker_compose run --rm -u pleroma -w /home/pleroma/pleroma "$debug_mounts" "$x_flags" server bash -c "cp -rvf /custom.d/* /home/pleroma/pleroma && $*"
    [[ $NO_X_FORWARDING == 1 ]] || xhost -local:root
}

action__mod() {
    require_command dialog
    require_command jq
    require_command curl

    if [[ ! -d ./debug.d ]]; then
        mkdir ./debug.d
    fi

    if [[ ! -f ./debug.d/mod_files.json ]] || [[ -n "$(find ./debug.d/mod_files.json -mmin +5)" ]]; then
        curl -sSL -# "$GITLAB_URI/$ENDPOINT_LIST/$PLEROMA_VERSION?format=json" > ./debug.d/mod_files.json

        if [[ -f ./debug.d/mod_files.lst ]]; then
            rm ./debug.d/mod_files.lst
        fi

        jq -r 'map("\(.)\n") | add' <./debug.d/mod_files.json >./debug.d/mod_files.lst
    fi

    if [[ -f ./debug.d/mod_files.lst ]] && [[ -r ./debug.d/mod_files.lst ]]; then
        choices=""

        while read -r candidate; do
            choices="$choices $candidate $(echo "$candidate" | rev | cut -d/ -f1 | rev)"
        done <<< "$(grep -E ".*$1.*" <./debug.d/mod_files.lst)"

        res=$(mktemp)
        dialog --menu "Select the file you want to modify:" 35 80 30 $choices 2>"$res"
        choice=$(cat "$res")

        install -D <(echo '') "./custom.d/$choice"
        curl -sSL -# "$GITLAB_URI/$ENDPOINT_FILE/$PLEROMA_VERSION/$choice" > "./custom.d/$choice"
    else
        install -D <(echo '') "./custom.d/$1"
        curl -sSL -# "$GITLAB_URI/$ENDPOINT_FILE/$PLEROMA_VERSION/$1" > "./custom.d/$1"
    fi
}

#########################################################
# Help                                                  #
#########################################################

print_help() {
    echo "
Pleroma Maintenance Script

Usage:
    $0 [action] [action-args...]

Actions:
    build                      (Re)build the pleroma container.

    dump                       Dump the generated docker-compose.yml to stdout.

    debug [bin] [args...]      Launches a new pleroma container but uses \$bin instead of phx.server as entrypoint.
                               **Warning**: This is intended for debugging pleroma with tools like :debugger and :observer.
                               It thus forwards your X-Server into docker and temporarily fiddles with your xhost
                               access controls. If this is a security concern for you, please export NO_X_FORWARDING=1
                               before launching a debugger session.

    enter                      Spawn a shell inside the container for debugging/maintenance.
                               This command does not link to the postgres container.
                               If you need that use #debug instead.

    logs                       Show the current container logs.

    mix [task] [args...]       Run a mix task without entering the container.

    mod [file]                 Creates the file in custom.d and downloads the content from pleroma.social.
                               The download respects your \$PLEROMA_VERSION from .env.

    passthrough / p [...]      Pass any custom command to docker-compose.

    restart                    Executes #stop and #start respectively.

    start / up                 Start pleroma and sibling services.

    stop / down                Stop pleroma and sibling services.

    status / ps                Show the current container status.

Environment:
    DEBUG can be used to modify the loglevel.
        DEBUG=1 prints all commands before they are executed.
        DEBUG=2 prints all bash statements before they are executed (a lot).

    SHOPT can be used to modify shell options.
        Pass a list of options to this variable like SHOPT='-x -e'.
        For setting long options with -o use a colon (:) instead of a space
        to seperate the option from -o. For example: SHOPT='-x -e -o:pipefail'.

Contributing:
    You can report bugs or contribute to this project at:
        https://glitch.sh/sn0w/pleroma-docker
"
}

#########################################################
# Main                                                  #
#########################################################

# Check if there is any command at all
if [[ -z "$1" ]]; then
    print_help
    exit 1
fi

# Check for SHOPTs
if [[ -n "$SHOPT" ]]; then
    for opt in $SHOPT; do
        if [[ $opt =~ ":" ]]; then
            set -o "${opt//-o:/}"
        else
            set "$opt"
        fi
    done
fi

# Check for DEBUG
if [[ -n "$DEBUG" ]]; then
    if [[ $DEBUG == 1 ]]; then
        export DEBUG_COMMANDS=1
    elif [[ $DEBUG == 2 ]]; then
        set -x
    fi
fi

# Check if the option is "help"
case "$1" in
    "help"|"h"|"--help"|"-h"|"-?")
        print_help
        exit 0
    ;;
esac

# Check if the called command exists
func="action__${1}"
if ! type -t "$func" 1>/dev/null 2>&1; then
    echo "Unknown flag or subcommand."
    echo "Try '$0 help'"
    exit 1
fi

# Fail if mandatory files are missing
require_file ".env" ".env.dist"
require_file "config.exs" "config.dist.exs"
throw_file_errors

# Parse .env
load_env

# Handle DEBUG=2
[[ $DEBUG != 1 ]] || set -x

# Jump to called function
shift
$func "$@"

# Disable debug mode
{ [[ $DEBUG != 1 ]] || set +x; } 2>/dev/null