Merge EXAMPLES into README, restructure, some corrections

[code/vcsh.git] / vcsh

#!/bin/sh

[ -n "$VCSH_DEBUG" ] && set -x

SELF=$(basename $0)

[ -z "$XDG_CONFIG_HOME" ] && XDG_CONFIG_HOME="$HOME/.config"
[ -z "$VCSH_BASE" ]       && VCSH_BASE="$XDG_CONFIG_HOME/vcsh/repo.d"
for check_directory in "$VCSH_BASE"
do
        if [ ! -d "$check_directory" ]; then
                if [ -e "$check_directory" ]; then
                        echo "$SELF: error: $check_directory exists but is not a directory" >&2
                        exit 2
                else
                        mkdir -p "$check_directory" || (echo "$SELF: error: could not create $check_directory" >&2; exit 2)
                fi
        fi
done

debug() {
        [ -n "$VCSH_DEBUG" ] && echo "$SELF: debug: $1"
}

verbose() {
        if [ -n "$VCSH_DEBUG" ] || [ -n "$VCSH_VERBOSE" ]; then echo "$SELF: verbose: $1"; fi
}

#   use <repo>     Use this repository
#
#   exit              Exit vcsh mode" >&2
help() {
        echo "usage: $SELF <args>

   help              Display this help

   list              List all repos

   run <repo> \\
       <command>     Use this repository

   init <repo>       Initialize a new repository
   clone <remote> \\
         [<repo>]    Clone from an existing repository
   seed-gitignore \\
   <repo>            Seed .gitignore.d/<repo> from git ls-files" >&2
}

use() {
        verbose "use() begin"
        REPO_NAME="$1"
        GIT_DIR="$VCSH_BASE/$REPO_NAME.git"

        if [ ! -d "$GIT_DIR" ]; then
                echo E: no repository found for "$REPO_NAME" >&2
                return 2
        fi

        export GIT_DIR
        export GIT_WORK_TREE="$(git config --get core.worktree)"
        export VCSH_DIRECTORY="$REPO_NAME"
        verbose "use() end"
}

init() {
        verbose "init() begin"
        [ -e "$GIT_DIR" ] &&
                echo "$SELF: fatal: $GIT_DIR exists" &&
                return 21
        export GIT_WORK_TREE="$HOME"
        mkdir -p "$GIT_WORK_TREE"
        cd "$GIT_WORK_TREE" ||
                (echo "$SELF: fatal: could not enter $GIT_WORK_TREE" &&
                 exit 20) || exit 20
        cd "$GIT_WORK_TREE"
        git init
        git config core.worktree "$GIT_WORK_TREE"
        verbose "init() end"
}

leave() {
        unset GIT_DIR
        unset GIT_WORK_TREE
        unset VCSH_DIRECTORY
}

if [ "$1" = 'help' ] || [ "$#" -eq 0 ]; then
        help
        [ "$1" = 'help' ]
        exit $?

elif [ "$1" = 'list' ]; then
        verbose "list begin"
        for i in "$VCSH_BASE"/*.git; do
                echo $(basename "$i" .git)
        done
        verbose "list end"
        exit 0

elif [ "$1" = 'run' ]; then
        verbose "run begin"
        use "$2"
        shift 2
        "$@"
        leave
        verbose "run end"
        exit 0

#elif [ "$1" = 'use' ]; then
#       verbose "use begin"
#       if [ -n "$ZSH_VERSION" ]; then
#               if [ -o NO_IGNORE_EOF ]; then
#                       export VCSH_NO_IGNORE_EOF=1
#                       setopt IGNORE_EOF
#               fi
#               vcsh_exit() {
#                       vcsh exit;
#                       zle reset-prompt;
#               }
#               zle -N vcsh_exit
#               bindkey '^d' 'vcsh_exit'
#       fi
#       use $2
#       [ -n "$ZSH_VERSION" ] && [ "$USER" = richih ] && buildPS1
#       verbose "use end"
#       exit 0

elif [ "$1" = 'clone' ]; then
        verbose "clone begin"
        GIT_REMOTE="$2"
        REPO_NAME="$3"
        [ -z "$REPO_NAME" ] && REPO_NAME=$(basename "$GIT_REMOTE" .git)
        export REPO_NAME
        export GIT_DIR="$VCSH_BASE/$REPO_NAME.git"
        init

        git remote add origin "$GIT_REMOTE"
        git config branch.master.remote origin
        git config branch.master.merge  refs/heads/master
        git fetch
        for object in $(git ls-tree -r origin/master | awk '{print $4}'); do
                [ -e "$object" ] &&
                        echo "$SELF: error: $object exists." &&
                        VCSH_CONFLICT=1;
        done
        [ "$VCSH_CONFLICT" = '1' ] &&
                echo "$SELF: fatal: will stop after fetching and not try to merge!\n" &&
                echo "  Once this situation has been resolved, run 'vcsh run <foo> git pull' to finish cloning.\n" &&
                exit 3
        git merge origin/master
#       vcsh use $REPO_NAME
        verbose "clone end"

elif [ "$1" = 'init' ]; then
        verbose "init begin"
        [ -z $2 ] && help && echo && echo "$SELF $1: please specify repository to work on" && return 0
        export REPO_NAME="$2"
        export GIT_DIR="$VCSH_BASE/$REPO_NAME.git"
        init
#       vcsh use "$REPO_NAME"
        verbose "init end"

#elif [ "$1" = 'exit' ]; then
#       verbose "exit begin"
#       if [ -n "$ZSH_VERSION" ] && [ "$VCSH_NO_IGNORE_EOF" = '1' ]; then
#               unset VCSH_NO_IGNORE_EOF
#               setopt NO_IGNORE_EOF
#       fi
#       leave
#       [ -n "$ZSH_VERSION" ] && [ "$USER" = richih ] && buildPS1
#       verbose "exit end"
#       exit 0

elif [ "$1" = 'seed-gitignore' ]; then
        verbose "seed-gitignore begin"
        [ -z $2 ] && help && echo && echo "$SELF $1: please specify repository to work on" && return 0
        use "$2"
        files=$(git ls-files)
        gitignores=$(for file in $(git ls-files); do
                while true; do
                        echo $file; new="${file%/*}"
                        [ "$file" = "$new" ] && break
                        file="$new"
                done;
        done | sort -u | sed 's/^/!/')
        [ -e .gitignore.d/$2 ] &&
        echo "$SELF: .gitignore.d/$2 exists, moving it to .gitignore.d/$2.bak" &&
        mv -f .gitignore.d/$2 .gitignore.d/$2.bak
        echo '*' > .gitignore.d/$2
        for gitignore in $gitignores; do
                echo $gitignore >> .gitignore.d/$2
        done

else
        verbose "defaulting to calling help()"
        help
        exit 3

fi