#!/usr/bin/env bash
#
# Copyright (c) 2024 YunoHost Contributors
#
# This file is part of YunoHost (see https://yunohost.org)
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU Affero General Public License as
# published by the Free Software Foundation, either version 3 of the
# License, or (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU Affero General Public License for more details.
#
# You should have received a copy of the GNU Affero General Public License
# along with this program. If not, see <http://www.gnu.org/licenses/>.
#

YNH_APT_INSTALL_DEPENDENCIES_REPLACE="true"

# Define and install dependencies with a equivs control file
#
# example : ynh_apt_install_dependencies dep1 dep2 "dep3|dep4|dep5"
#
# usage: ynh_apt_install_dependencies dep [dep [...]]
# | arg: dep - the package name to install in dependence.
# | arg: "dep1|dep2|…" - You can specify alternatives. It will require to install (dep1 or dep2, etc).
#
ynh_apt_install_dependencies() {

    # Add a comma for each space between packages. But not add a comma if the space separate a version specification. (See below)
    local dependencies="$(sed 's/\([^\<=\>]\)\ \([^(]\)/\1, \2/g' <<< "$@" | sed 's/|/ | /')"
    local version=$(ynh_read_manifest "version")
    local app_ynh_deps="${app//_/-}-ynh-deps" # Replace all '_' by '-', and append -ynh-deps

    # Handle specific versions
    if grep '[<=>]' <<< "$dependencies"; then
        # Replace version specifications by relationships syntax
        # https://www.debian.org/doc/debian-policy/ch-relationships.html
        # Sed clarification
        # [^(\<=\>] ignore if it begins by ( or < = >. To not apply twice.
        # [\<=\>] matches < = or >
        # \+ matches one or more occurence of the previous characters, for >= or >>.
        # [^,]\+ matches all characters except ','
        # Ex: 'package>=1.0' will be replaced by 'package (>= 1.0)'
        dependencies="$(sed 's/\([^(\<=\>]\)\([\<=\>]\+\)\([^,]\+\)/\1 (\2 \3)/g' <<< "$dependencies")"
    fi

    # ############################## #
    # Specific tweaks related to PHP #
    # ############################## #

    # Check for specific php dependencies which requires sury
    # This grep will for example return "7.4" if dependencies is "foo bar php7.4-pwet php-gni"
    # The (?<=php) syntax corresponds to lookbehind ;)
    local specific_php_version=$(grep -oP '(?<=php)[0-9.]+(?=-|\>|)' <<< "$dependencies" | sort -u)

    if [[ -n "$specific_php_version" ]]; then
        # Cover a small edge case where a packager could have specified "php7.4-pwet php5-gni" which is confusing
        [[ $(echo "$specific_php_version" | wc -l) -eq 1 ]] \
            || ynh_die "Inconsistent php versions in dependencies ... found : $specific_php_version"

        dependencies+=", php${specific_php_version}, php${specific_php_version}-fpm, php${specific_php_version}-common"

        local old_php_version=$(ynh_app_setting_get --key=php_version)

        # If the PHP version changed, remove the old fpm conf
        if [ -n "$old_php_version" ] && [ "$old_php_version" != "$specific_php_version" ]; then
            if [[ -f "/etc/php/$php_version/fpm/pool.d/$app.conf" ]]; then
                ynh_backup_if_checksum_is_different "/etc/php/$php_version/fpm/pool.d/$app.conf"
                ynh_config_remove_phpfpm
            fi
        fi
        # Store php_version into the config of this app
        ynh_app_setting_set --key=php_version --value="$specific_php_version"

        # Set the default php version back as the default version for php-cli.
        if test -e "/usr/bin/php$YNH_DEFAULT_PHP_VERSION"; then
            update-alternatives --set php "/usr/bin/php$YNH_DEFAULT_PHP_VERSION"
        fi
    # Otherwise force php_version back to the default version ...
    # ... except we don't want to do this when appending the "extra" dependencies if they don't contain a php version ...
    elif grep --quiet 'php' <<< "$dependencies" && [[ $YNH_APT_INSTALL_DEPENDENCIES_REPLACE == "true" ]]; then
        ynh_app_setting_set --key=php_version --value="$YNH_DEFAULT_PHP_VERSION"
    fi

    # Specific tweak related to Postgresql (cf end of the helper)
    local psql_installed="$(_ynh_apt_package_is_installed "postgresql-$PSQL_VERSION" && echo yes || echo no)"

    # The first time we run ynh_apt_install_dependencies, we will replace the
    # entire control file (This is in particular meant to cover the case of
    # upgrade script where ynh_apt_install_dependencies is called with this
    # expected effect) Otherwise, any subsequent call will add dependencies
    # to those already present in the equivs control file.
    if [[ $YNH_APT_INSTALL_DEPENDENCIES_REPLACE == "true" ]]; then
        YNH_APT_INSTALL_DEPENDENCIES_REPLACE="false"
    else
        local current_dependencies=""
        if _ynh_apt_package_is_installed "${app_ynh_deps}"; then
            current_dependencies="$(dpkg-query --show --showformat='${Depends}' "${app_ynh_deps}") "
            current_dependencies=${current_dependencies// | /|}
        fi
        dependencies="$current_dependencies, $dependencies"
    fi

    # ################
    # Actual install #
    # ################

    # Prepare the virtual-dependency control file for dpkg-deb --build
    local TMPDIR=$(mktemp --directory)
    mkdir -p "${TMPDIR}/${app_ynh_deps}/DEBIAN"
    # For some reason, dpkg-deb insists for folder perm to be 755 and sometimes it's 777 o_O?
    chmod -R 755 "${TMPDIR}/${app_ynh_deps}"

    cat > "${TMPDIR}/${app_ynh_deps}/DEBIAN/control" << EOF
Section: misc
Priority: optional
Package: ${app_ynh_deps}
Version: ${version}
Depends: ${dependencies//,,/,}
Architecture: all
Maintainer: root@localhost
Description: Fake package for ${app} (YunoHost app) dependencies
 This meta-package is only responsible of installing its dependencies.
EOF

    _ynh_apt update --error-on=any

    _ynh_wait_dpkg_free

    # Install the fake package without its dependencies with dpkg --force-depends
    if ! LC_ALL=C dpkg-deb --build "${TMPDIR}/${app_ynh_deps}" "${TMPDIR}/${app_ynh_deps}.deb" > "${TMPDIR}/dpkg_log" 2>&1; then
        cat "${TMPDIR}/dpkg_log" >&2
        ynh_die "Unable to install dependencies"
    fi
    # Don't crash in case of error, because is nicely covered by the following line
    LC_ALL=C dpkg --force-depends --install "${TMPDIR}/${app_ynh_deps}.deb" 2>&1 | tee "${TMPDIR}/dpkg_log" || true

    # Then install the missing dependencies with apt install
    _ynh_apt_install --fix-broken || {
        # If the installation failed
        # (the following is ran inside { } to not start a subshell otherwise ynh_die wouldnt exit the original process)
        # Parse the list of problematic dependencies from dpkg's log ...
        # (relevant lines look like: "foo-ynh-deps depends on bar; however:")
        cat "$TMPDIR/dpkg_log"
        local problematic_dependencies
        mapfile -t problematic_dependencies < <(grep -oP '(?<=-ynh-deps depends on ).*(?=; however)' "$TMPDIR/dpkg_log")
        # Fake an install of those dependencies to see the errors
        # The sed command here is, Print only from 'Reading state info' to the end.
        if ((${#problematic_dependencies[@]} != 0)); then
            _ynh_apt_install "${problematic_dependencies[@]}" --dry-run 2>&1 | sed --quiet '/Reading state info/,$p' | grep -v "fix-broken\|Reading state info" >&2
        fi
        ynh_die "Unable to install apt dependencies, it might be due to a conflict with another app - or you should check and share the previous log about what are the problematic dependencies"
    }
    rm --recursive --force "$TMPDIR" # Remove the temp dir.

    # check if the package is actually installed
    _ynh_apt_package_is_installed "${app_ynh_deps}" || ynh_die "Unable to install apt dependencies"

    # Specific tweak related to Postgresql
    # -> trigger postgresql regenconf if we may have just installed postgresql
    local psql_installed2="$(_ynh_apt_package_is_installed "postgresql-$PSQL_VERSION" && echo yes || echo no)"
    if [[ "$psql_installed" != "$psql_installed2" ]]; then
        yunohost tools regen-conf postgresql
    fi

}

# Remove fake package and its dependencies
#
# Dependencies will removed only if no other package need them.
#
# usage: ynh_apt_remove_dependencies
ynh_apt_remove_dependencies() {
    local app_ynh_deps="${app//_/-}-ynh-deps" # Replace all '_' by '-', and append -ynh-deps

    local current_dependencies=""
    if _ynh_apt_package_is_installed "${app_ynh_deps}"; then
        current_dependencies="$(dpkg-query --show --showformat='${Depends}' "${app_ynh_deps}") "
        current_dependencies=${current_dependencies// | /|}
    fi

    # Edge case where the app dep may be on hold,
    # cf https://forum.yunohost.org/t/migration-error-cause-of-ffsync/20675/4
    if apt-mark showhold | grep -q -w "${app_ynh_deps}"; then
        apt-mark unhold "${app_ynh_deps}"
    fi

    # Remove the fake package and its dependencies if they not still used.
    # (except if dpkg doesn't know anything about the package,
    # which should be symptomatic of a failed install, and we don't want bash to report an error)
    if dpkg-query --show "${app_ynh_deps}" &> /dev/null; then
        _ynh_apt autoremove --purge "${app_ynh_deps}"
    fi
}

# Install packages from an extra repository properly.
#
# usage: ynh_apt_install_dependencies_from_extra_repository --repo="repo" --package="dep1 dep2" --key=key_url
# | arg: --repo=    - Complete url of the extra repository.
# | arg: --package= - The packages to install from this extra repository
# | arg: --key=     - url to get the public key.
#
ynh_apt_install_dependencies_from_extra_repository() {
    # ============ Argument parsing =============
    local -A args_array=([r]=repo= [p]=package= [k]=key=)
    local repo
    local package
    local key
    ynh_handle_getopts_args "$@"
    # ===========================================

    # split package into packages list
    local packages
    read -r -a packages <<< "$package"

    # Split the repository into uri, suite and components.
    IFS=', ' read -r -a repo_parts <<< "$repo"
    index=0

    # Remove "deb " at the beginning of the repo.
    if [[ "${repo_parts[0]}" == "deb" ]]; then
        index=1
    fi
    uri="${repo_parts[$index]}"
    index=$((index + 1))
    suite="${repo_parts[$index]}"
    index=$((index + 1))

    # Get the components
    if (("${#repo_parts[@]}" > 0)); then
        component="${repo_parts[*]:$index}"
    fi

    if [[ "$key" == "trusted=yes" ]]; then
        trust="[trusted=yes]"
    else
        trust=""
    fi

    # Add the new repo in sources.list.d
    mkdir --parents "/etc/apt/sources.list.d"
    echo "deb $trust $uri $suite $component" > "/etc/apt/sources.list.d/$app.list"

    # Pin the new repo with the default priority, so it won't be used for upgrades.
    # Build $pin from the uri without http and any sub path
    local pin="${uri#*://}"
    pin="${pin%%/*}"

    # Pin repository
    mkdir --parents "/etc/apt/preferences.d"
    cat << EOF > "/etc/apt/preferences.d/$app"
Package: *
Pin: origin $pin
Pin-Priority: 995
EOF

    if [ -n "$key" ] && [[ "$key" != "trusted=yes" ]]; then
        mkdir --parents "/etc/apt/trusted.gpg.d"
        # Timeout option is here to enforce the timeout on dns query and tcp connect (c.f. man wget)
        wget --timeout 900 --quiet "$key" --output-document=- | gpg --dearmor > "/etc/apt/trusted.gpg.d/$app.gpg"
    fi

    # Update the list of package with the new repo NB: we use -o
    # Dir::Etc::sourcelist to only refresh this repo, because
    # ynh_apt_install_dependencies will also call an ynh_apt update on its own
    # and it's good to limit unecessary requests ...  Here we mainly want to
    # validate that the url+key is correct before going further
    _ynh_apt update --error-on=any -o Dir::Etc::sourcelist="/etc/apt/sources.list.d/$app.list"

    # Force the cache to be reupdated on the next "apt update" (in
    # ynh_apt_install_dependencies) because the previous command with
    # ::sourcelist option makes apt forget about every other package for other,
    # so we want to force the cache to be reupdated entirely
    touch "/etc/apt/sources.list.d/$app.list"

    # Install requested dependencies from this extra repository.
    # NB: because of the mechanism with $ynh_apt_install_DEPENDENCIES_REPLACE,
    # this will usually only *append* to the existing list of dependency, not
    # replace the existing $app-ynh-deps
    ynh_apt_install_dependencies "$package"

    # Force to upgrade to the last version...
    # Without doing apt install, an already installed dep is not upgraded
    local apps_auto_installed
    mapfile -t apps_auto_installed < <(apt-mark showauto "${packages[@]}")
    _ynh_apt_install "${packages[@]}"
    if ((${#apps_auto_installed[@]} != 0)); then
        apt-mark auto "${apps_auto_installed[@]}"
    fi

    # Remove this extra repository after packages are installed
    ynh_safe_rm "/etc/apt/sources.list.d/$app.list"
    ynh_safe_rm "/etc/apt/preferences.d/$app"
    ynh_safe_rm "/etc/apt/trusted.gpg.d/$app.gpg"
    _ynh_apt update --error-on=any
}

# #####################
# Internal misc utils #
# #####################

# Check if apt is free to use, or wait, until timeout.
_ynh_wait_dpkg_free() {
    local try
    set +o xtrace # set +x
    # With seq 1 17, timeout will be almost 30 minutes
    for try in $(seq 1 17); do
        # Check if /var/lib/dpkg/lock is used by another process
        if lsof /var/lib/dpkg/lock > /dev/null; then
            echo "apt is already in use..."
            # Sleep an exponential time at each round
            sleep $((try * try))
        else
            # Check if dpkg hasn't been interrupted and is fully available.
            # See this for more information: https://sources.debian.org/src/apt/1.4.9/apt-pkg/deb/debsystem.cc/#L141-L174
            local dpkg_dir="/var/lib/dpkg/updates/"

            # For each file in $dpkg_dir
            while read -r dpkg_file <&9; do
                # Check if the name of this file contains only numbers.
                if echo "$dpkg_file" | grep --perl-regexp --quiet "^[[:digit:]]+$"; then
                    # If so, that a remaining of dpkg.
                    ynh_print_warn "dpkg was interrupted, you must manually run 'sudo dpkg --configure -a' to correct the problem."
                    set -o xtrace # set -x
                    return 1
                fi
            done 9<<< "$(ls -1 $dpkg_dir)"
            set -o xtrace # set -x
            return 0
        fi
    done
    echo "apt still used, but timeout reached !"
    set -o xtrace # set -x
}

# Check either a package is installed or not
_ynh_apt_package_is_installed() {
    local package=$1
    dpkg-query --show --showformat='${db:Status-Status}' "$package" 2> /dev/null \
        | grep --quiet "^installed$" &> /dev/null
}

# Return the installed version of an apt package, if installed
_ynh_apt_package_version() {
    if _ynh_apt_package_is_installed "$package"; then
        dpkg-query --show --showformat='${Version}' "$package" 2> /dev/null
    else
        echo ''
    fi
}

# APT wrapper for non-interactive operation
_ynh_apt() {

    # Optimization when just calling apt update : check if the cache was
    # already refreshed in the last 30 min, which should be enough and prevent
    # unecessary traffic and annoying wait time during app dependency installs etc
    if [[ "$*" == "update" ]]; then
        # trick from https://stackoverflow.com/a/205710
        local aptcache="/var/cache/apt/pkgcache.bin"
        sleep 1
        if [[ -e $aptcache ]] && [[ -n "$(find $aptcache -mmin -30)" ]] && [[ -z "$(find /etc/apt/ -newer $aptcache)" ]]; then
            echo "apt cache was already updated in the last 30 minutes, skipping 'apt update'"
            return
        fi
    fi

    _ynh_wait_dpkg_free
    LC_ALL=C DEBIAN_FRONTEND=noninteractive apt-get --assume-yes --quiet -o=Acquire::Retries=3 -o=Dpkg::Use-Pty=0 "$@"
}

# Wrapper around "apt install" with the appropriate options
_ynh_apt_install() {
    _ynh_apt --no-remove --option Dpkg::Options::=--force-confdef \
        --option Dpkg::Options::=--force-confold install "$@"
}