#!/usr/bin/env zsh
## pkg - /home package manager and zsh playground
## Copyright (C) 2008 Daniel Friesel <derf@derf.homelinux.org>
## 
## Permission to use, copy, modify, and/or distribute this software for any
## purpose with or without fee is hereby granted, provided that the above
## copyright notice and this permission notice appear in all copies.
##
## THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
## WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
## MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
## ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
## WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
## ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
## OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.

typeset -a -U triggers

##
## Internal functions for displaying stuff
##

info=$'\e[0;36m'
error=$'\e[0;31m'
reset=$'\e[0m'

function debug {
	typeset func line
	if [[ ${#*} -ge 3 ]] {
		func=$1
		line=$2
		shift 2
	}
	echo "(debug) $func:$line: $*" >&2
}

# I need function name and line number of the function _calling_ debug,
# so I can't get them from inside the debug function.
alias debug='debug ${(%):-%N} ${(%):-%i}'

function info {
	(( SILENT )) || echo -ne "${info}$*${reset}"
}

function warn {
	echo -ne "${error}$*${reset}" > /dev/stderr
}

function die {
	echo -ne "${error}$*${reset}" > /dev/stderr
	exit 100
}

function say {
	(( SILENT )) || echo $*
}

function check_installed {
	[[ -n $1 && -d $PDIR/$1 ]] || die "Not installed: '$1'\n"
}

function check_valid {
	if ! list_exists $1; then
		die "No such package: '$1'\n"
	fi
}

function clear_line {
	(( SILENT )) || echo -ne "\r\e[2K"
}

# Read local configuration
if [[ -f $HOME/.pkg.conf ]] {
	. $HOME/.pkg.conf
}

# Default values... or not
[[ -n $PKG_ROOT ]] || die "No PKG_ROOT specified. Please edit ~/.pkg.conf\n"
: ${PDIR:="$HOME/packages"}
: ${CL_OPTIONS:=-q}
: ${SILENT=0}
: ${DEBUG=0}
: ${AUTOUPDATE=1}

export PDIR
export PKG_ROOT

##
## commandline parsing
##

# commandline options override everything else
while [[ $1 == [-+]* ]] {
	case $1 in
		-q|--quiet) SILENT=1 ;;
		+q|--no-quiiet) SILENT=0 ;;
		-d|--debug) DEBUG=1 ;;
		+d|--no-debug) DEBUG=0 ;;
		-au|--auto-update) AUTOUPDATE=1 ;;
		+au|--no-auto-update) AUTOUPDATE=0 ;;
		-co|--checklinks-options) CL_OPTIONS+=$1; shift ;;
		-p|--packagedir) PDIR=$1; shift ;;
		*) die "Unknown argument: '$1'\n" ;;
	esac
	shift
}

action=$1
shift

# Avoid calling debug without debug mode... just in case one needs more speed
if (( !DEBUG )) {
	unalias debug
	function debug {}
}

if (( SILENT )) {
	# The goal is not to override anything set by the user...
	# So, an alias should be safer than fiddling with $MAKEFLAGS
	alias make='make -s'
}

##
## Make sure everything's sane
## Warn otherwise
##

if [[ ! -d $PDIR ]] {
	die "Error: Package directory '$PDIR' not found\n"
}


##
## Setup some additional variables related to PKG_ROOT
##

# Protocol
if [[ ${PKG_ROOT#ssh} != $PKG_ROOT ]] {
	PKG_PROTO='ssh'
} elif [[ ${PKG_ROOT#'/'} != $PKG_ROOT ]] {
	PKG_PROTO='file'
} else {
	die "Error: Unknown protocol in PKG_ROOT '$PKG_ROOT'"
}

# user, host, path
if [[ $PKG_PROTO == 'ssh' ]] {
	PKG_HOST=${${PKG_ROOT#'ssh://'}%%/*}
	PKG_PATH=${PKG_ROOT#"ssh://$PKG_HOST"}
	if [[ $PKG_HOST == *@* ]] {
		PKG_USER=${PKG_HOST%%@*}
		PKG_HOST=${PKG_HOST#*@}
	} else {
		PKG_USER=$USERNAME
	}
} elif [[ $PKG_PROTO == 'file' ]] {
	PKG_PATH=$PKG_ROOT
}

debug "PKG_ROOT: '$PKG_ROOT'"
debug "PKG_PROTO: '$PKG_PROTO'"
debug "PKG_USER: '$PKG_USER'"
debug "PKG_HOST: '$PKG_HOST'"

##
## Ask the user for confirmation
##

# Default reply: Yes
function confirm_yes {
	echo -n "$* [Y/n] "
	read -k 1
	[[ $REPLY != $'\n' ]] && echo
	if [[ $REPLY == 'y' || $REPLY == 'Y' || $REPLY == $'\n' ]] {
		true
	} else {
		false
	}
}

# Default reply: No
function confirm_no {
	echo -n "$* [y/N] "
	read -q
}


##
## Major internal functions
##

function wrap_info {}

function progress {
	(( SILENT )) && return
	current=$1
	max=$2
	desc=$3
	desc2=$4
	output=''
	currentper=$(( (current*100)/max ))
	function item {
		for j in {0..$1}; {
			(( j > 0 )) && output+=$2
		}
	}
	clear_line
	c=$(( currentper/5 ))
	a=$(( 20-c ))
	output+="${info}$desc${reset} ["
	item $c '='
	item $a ' '
	output+="] $currentper% $desc2"
	echo -ne $output
}

## VCS Wrappers
function vcs_to_list {
	if [[ -d $1/.git ]] {
		echo -n "$1 git "
		echo ${$(git --git-dir=$1/.git log -n 1 master)[2]}
	} else {
		warn "No git repository found: $1\n"
	}
}

function vcs_add {
	cd $PDIR
	case $(list_type $1) in
		git)   git clone "$PKG_ROOT/$1" ;;
		*)     die "$1: Cannot handle repository format '$(list_type $1)'\n" ;;
	esac
}

function vcs_log {
	git log
}

function vcs_upgrade {
	typeset IFS=$'\n' line
	typeset branch
	for line in $(git branch); {
		[[ $line == \*\ * ]] && branch=${line#* }
	}
	debug "branch = $branch"
	if [[ -z $branch ]] {
		warn "vcs_upgrade: $PWD: cannot determine current branch, not pulling"
		return 1
	}
	git pull $PKG_ROOT/${PWD:t} $branch
}

function vcs_push {
	git push $PKG_ROOT/${PWD:t} master
}

function vcs_status {
	git status
}

## List stuff

function list_is_installed {
	grep "^$1 " $PDIR/.list &> /dev/null
}

function list_exists {
	grep "^$1 " $PDIR/.list-remote &> /dev/null
}

function list_incoming {
	[[ $(list_local_version $1) != $(list_remote_version $1) ]]
}

function list_type {
	echo ${$(grep "^$1 " $PDIR/.list-remote)[2]}
}

function list_type_local {
	echo ${$(grep "^$1 " $PDIR/.list)[2]}
}

function list_update_remote {
	export PDIR
	if [[ $PKG_PROTO == 'ssh' ]] {
		ssh $PKG_USER@$PKG_HOST "PDIR='$PDIR' $PKG_PATH/core/include/pkglist $PKG_PATH" > .list-remote
	} elif [[ $PKG_PROTO == 'file' ]] {
		$PKG_PATH/core/include/pkglist $PKG_PATH > .list-remote
	}
}

function list_update_local {
	cd $PDIR
	rm -f .list
	all=${#$(echo $PDIR/*(/))}
	current=0
	for i in *(/); {
		(( current++ ))
		progress $current $all 'Updating package list' $i
		vcs_to_list $i >> .list
	}
}

function list_update_package {
	cd $PDIR
	list=$(grep -v "^$1 " .list)
	echo $list > .list
	vcs_to_list $1 >> .list
}

function list_remove_package {
	cd $PDIR
	list=$(grep -v "^$1 " .list)
	echo $list > .list
}

function list_local_version {
	echo ${$(grep "^$1 " $PDIR/.list)[3]}
}

function list_remote_version {
	echo ${$(grep "^$1 " $PDIR/.list-remote)[3]}
}


# Return an understandable priority from the numeric one
function real_priority {
	case $1 in
		6) echo 'essential' ;;
		5) echo 'important' ;;
		4) echo 'required' ;;
		3) echo 'standard' ;;
		2) echo 'optional' ;;
		1) echo 'extra' ;;
		*) echo ;;
	esac
}

# Execute a hook
function exec_hook {
	package=$1
	hook=$2
	if [[ -r $PDIR/$package/hooks/$hook ]] {
		info "$package: executing hook $hook\n"
		cd $PDIR/$package
		(source hooks/$hook)
	}
}

function global_hook {
	cd $PDIR/$1
	case $2 in
		post-add)
			exec_hook $1 post-add
			global_hook $1 post-update
		;;
		pre-update)
		;;
		post-update)
			triggers+=$1
			check_prereqs $1
			if [[ -r Makefile ]] {
				wrap_info $1
				info "Running make\n"
				make
			}
			checklinks $CL_OPTIONS
			populate_collected $1
			update_provides $1
			fix_origin $1
			list_update_package $1
		;;
		pre-remove)
			exec_hook $1 pre-remove
			genocide_collected $1
			checklinks -r
			list_remove_package $1
			update_provides $1 'remove'
		;;
	esac
	(( $+functions[pkg_hook_$2] )) && pkg_hook_$2 $1
}

# Set the correct origin
function fix_origin {
	cd $PDIR/$1
	if ! git remote | grep -F origin &> /dev/null; then
		git remote add origin $PKG_ROOT/$1
	fi
	git remote update &> /dev/null
}

# Check dependencies, conflicts etc.
function check_prereqs {
	package=$1
	[[ -r $PDIR/$package/prereqs ]] || return 0
	cd $PDIR/$package
	wrap_info $1
	info "checking prerequisites\n"
	typeset -a -U install maybe_install
	typeset warn info

	function is_installed {
		[[ -d $PDIR/$1 ]]
	}
	function perlmodule {
		perl -M$1 < /dev/null 2> /dev/null
	}
	function file_in_path {
		which $1 > /dev/null
	}
	function offer_install {
		install+=$1
	}
	function require {
		if [[ $1 == 'package' ]] {
			is_installed $2 || offer_install $2
		} else {
			$* || warn+="Requirement failed: $*\n"
		}
	}
	function depend {
		require $*
	}

	function suggest {
		if [[ $1 == 'package' ]] {
			is_installed $2 || info "$package suggests package $2\n"
		} else {
			$* || info "Suggest failed: $*\n"
		}
	}

	function recommend {
		if [[ $1 == 'package' ]] {
			is_installed $2 || maybe_install+=$2
		} else {
			$* || info+="Recommend failed: $*\n"
		}
	}

	{
		source prereqs
	} always {
		if (( TRY_BLOCK_ERROR )) {
			warn "Error in prereqs script\n"
			TRY_BLOCK_ERROR=0
		}
	}

	if [[ -n $warn || -n $info ]] {
		warn $warn
		info $info
		read -q
	}

	if [[ -n $install ]] {
		info "$1 requires the following packages: ${(j:, :)install}\n"
		if confirm_yes "Install them?"; then
			for i in $install; {
				pkg_add $i
			}
		fi
	}
	if [[ -n $maybe_install ]] {
		info "$1 recommends the following packages: ${(j:, :)maybe_install}\n"
		if confirm_no "Install them?"; then
			for i in $maybe_install; {
				pkg_add $i
			}
		fi
	}
}

# Write a package's documentation to .collected
# and symlink it's binaries from ~/bin
function populate_collected {
	cd $PDIR/$1 || return
	typeset -i bins=0 bino=0 mans=0 mano=0

	wrap_info $1
	info "Enabling documentation "
	if [[ -d man ]] {
		for i in man/*/*; {
			section=${i:h:t}
			manpage=${i:t}
			if (podchecker man/$section/$manpage &> /dev/null) {
				pod2man -s $section -c "$1 package" -r $HOME man/$section/$manpage > $PDIR/.collected/man/man$section/$manpage.$section
				say -n "+"
				(( mans++ ))
			} else {
				say -n "."
				(( mano++ ))
			}
		}
	}
	if [[ -d bin ]] {
		for i in bin/*; {
			if (podchecker $i &> /dev/null) {
				pod2man $i > $PDIR/.collected/man/man1/${i:t}.1
				say -n "+"
				(( bins++ ))
			} else {
				say -n "."
				(( bino++ ))
			}
		}
	}
	clear_line
	if (( bins + mans > 0 )) {
		wrap_info $1
		info "Compiled documentation "
		say -n '('
		if (( bins + bino > 0 )) {
			say -n "$(( bins*100/(bins+bino) ))% bin"
			(( mans + mano > 0 )) && say -n ', '
		}
		if (( mans + mano > 0 )) {
			say -n "$(( mans*100/(mans+mano) ))% man"
		}
		say ')'
	}
	if [[ -d bin ]] {
		for i in bin/*(*); {
			if [[ -L $HOME/$i || ! -e $HOME/$i ]] {
				if [[ $(readlink $HOME/$i) != "../$1/$i" ]] {
					rm -f $HOME/$i
					ln -s ../${PDIR//$HOME\/}/$1/$i $HOME/$i
				}
			} else {
				warn "populate_collected: Not updating ~/$i since it's not a symlink\n"
			}
		}
	}
}

# Remove a package's files from .collected
# Assuming there are no packages with colliding files
# TODO: Make sure there are none
function genocide_collected {
	cd $PDIR/$1 || return
	wrap_info $1
	info "Removing documentation"
	if [[ -d man ]] {
		for i in man/*/*; {
			section=${i:h:t}
			manual=${i:t}
			if [[ -e $PDIR/.collected/man/man$section/$manual ]] {
				rm $PDIR/.collected/man/man$section/$manual
			}
		}
	}
	if [[ -d bin ]] {
		for i in bin/*; {
			rm -f $PDIR/.collected/man/man1/${i:t}.1
		}
	}
	clear_line
	if [[ -d bin ]] {
		for i in bin/*(*); {
			if [[ $(readlink $HOME/$i) = "../${PDIR//$HOME\/}/$1/$i" ]] {
				rm -f $HOME/$i
			}
		}
	}
}

function update_provides {
	[[ -d $PDIR/$1/provides ]] || return
	cd $PDIR/$1/provides
	for package in *; {
		if [[ -d $PDIR/$package ]] {
			[[ $2 = 'remove' ]] && rm -r $package
			triggers+=$package
		}
	}
}

function apply_triggers {
	for package in $triggers; {
		exec_hook $package 'post-update'
	}
}

# Iterate a function over every installed package
function wrap {
	function=$1
	arg=$2
	progress=$3

	if [[ -n $2 ]] {
		wrapped=0
		$function $2
	} else {
		wrapped=1
		function wrap_info {
			clear_line
			info "$1: "
		}
		cd $PDIR
		[[ -n $progress ]] && all=$(wc -l < $PDIR/.list)
		[[ -n $progress ]] && current=0
		for i in *(/); {
			(( current++ ))
			[[ -n $progress ]] && progress $current $all $progress $i
			$function $i
		}
		[[ -n $progress ]] && clear_line
	}
}

##
## Finally - the functions actually doing something
##

function pkg_add {
	if [[ -d $PDIR/$1 ]] {
		info "Package '$1' is already installed!\n"
		return 100
	}
	list_exists $1 || die "No such package: $1\n"
	info "Retrieving package $1...\n"
	cd $PDIR   || return 255
	vcs_add $1 || return 255
	cd $1      || return 255
	global_hook $1 post-add
}

function pkg_push {
	check_installed $1
	check_valid $1
	cd $PDIR/$1
	list_incoming $1
	if [[ $? = 0 ]] {
		clear_line
		info "Pushing $1\n"
		global_hook $1 pre-update
		vcs_push
		global_hook $1 post-update
	}
}

function pkg_remove {
	check_installed $1
	cd $PDIR/$1
	if [[ -r priority ]] {
		if (( $(cat priority) > 3 )) {
			confirm_no "Package '$1' is $(real_priority $(cat priority)). Really remove?" || return
		}
	}
	global_hook $1 pre-remove
	rm -rf $PDIR/$1
	info "Package removed.\n"
}

function pkg_upgrade {
	check_installed $1
	check_valid $1
	cd $PDIR/$1
	if [[ $(list_type $1) != $(list_type_local $1) ]] {
		clear_line
		warn "Incompatible systems. Please reinstall: $1\n"
		warn "  remote '$(list_type $1)' <-> local '$(list_type_local)'\n"
		return 9
	}
	if list_incoming $1; then
		clear_line
		info "Updating $1 to $(list_remote_version $1)\n"
		global_hook $1 pre-update
		vcs_upgrade
		global_hook $1 post-update
	fi
}

function pkg_list_installed {
	cut -d ' ' -f 1 $PDIR/.list
}

function pkg_list_available {
	cut -d ' ' -f 1 $PDIR/.list-remote
}

function pkg_status {
	check_installed $1
	cd $PDIR/$1
	vcs_status=$(PAGER='' vcs_status $1)
	if [[ -n $vcs_status && $(echo $vcs_status | tail -n 1) != 'nothing to commit (working directory clean)' ]] {
		clear_line
		info "$1:\n"
		echo $vcs_status
	}
}

function pkg_refresh {
	check_installed $1
	cd $PDIR/$1
	global_hook $1 pre-update
	if [[ -r Makefile ]] {
		wrap_info $1
		info "Cleaning build diroctery\n"
		make clean
	}
	global_hook $1 post-update
}

function pkg_update {
	pkg_update_remote
	pkg_update_local
}

function pkg_update_remote {
	cd $PDIR
	info "Updating remote package list..."
	list_update_remote
	clear_line
}

function pkg_update_local {
	info "Updating local package list..."
	list_update_local
	clear_line
}

# Various information related to a package
function pkg_info {
	cd $PDIR

	check_valid $1

	# Fetch the infos
	NAME=$1
	LOCAL_VERSION=$(list_local_version $1)
	REMOTE_VERSION=$(list_remote_version $1)
	REPO_TYPE=$(list_type $1)
	if [[ -d $1 ]] {
		cd $1
		if [[ -r priority ]] {
			PRIORITY=$(cat priority)
			PRIORITY_NAME=$(real_priority "$PRIORITY")
		}
		if [[ -r tags ]] {
			TAGS=$(cat tags | tr "\n" " " | sed 's/ /, /g' | sed 's/, $//')
		}
		if [[ -d hooks ]] {
			HOOKS=$(ls -m hooks)
		}
		if [[ -r Makefile ]] {
			MAKEFILE=1
		}
		SIZE=$(du -sh .$(list_type $1) | grep -o '.*[KMG]')
		if [[ -r description ]] {
			DESCRIPTION=$(cat description)
		}
		state='installed'
		if list_incoming $1; then
			state+=', needs update'
		else
			state+=', up-to-date'
		fi
	} else {
		state='not installed'
	}

	function show_info {
		[[ -z $2 ]] && return
		info "$1: "
		echo $2
	}

	show_info "Package" $NAME
	show_info 'State' $state
	[[ -n $PRIORITY ]] && show_info "Priority" "$PRIORITY ($PRIORITY_NAME)"
	show_info "Local Version" $LOCAL_VERSION
	show_info "Remote Version" $REMOTE_VERSION
	show_info "Repository Type" $REPO_TYPE
	show_info "Repository Size" $SIZE
	show_info "Tags" $TAGS
	show_info "Hooks" $HOOKS
	show_info "Description" $DESCRIPTION
}

function pkg_log {
	check_installed $1
	cd $PDIR/$1
	vcs_log
}


##
## Now what shall we do...
##

# Note:
# wrap foobar "$1" <- the "" are neccessary here, since $1 is optional (and therefore may be empty)
case $action in
	add) pkg_add $* ;;
	delete) pkg_remove $* ;;
	info) pkg_info $* ;;
	install) pkg_add $* ;;
	list) pkg_list_installed $* ;;
	list-all) pkg_list_available $* ;;
	local-update) pkg_update_local $* ;;
	log) pkg_log $* ;;
	push)
		(( AUTOUPDATE )) && pkg_update
		wrap pkg_push "$1" 'Pushing'
	;;
	refresh) wrap pkg_refresh "$1" 'Refreshing' ;;
	remote-update) pkg_update_remote $* ;;
	remove) pkg_remove $* ;;
	status) wrap pkg_status "$1" 'Checking package status' ;;
	update) pkg_update $* ;;
	upgrade|pull)
		(( AUTOUPDATE )) && pkg_update_remote
		wrap pkg_upgrade "$1" 'Looking for updates'
	;;
	eval) eval $* ;;
	*) die "wait, what?\npkg: unknown action: '$action'\n" ;;
esac

apply_triggers