dotfiles/script_helpers/file_ops.sh

#!/usr/bin/env bash

# Requires the printing.sh helper to be sourced.
# Requires the platform.sh helper to be sourced.

#---------------------------------------------------------------------------------------------------
# API
#---------------------------------------------------------------------------------------------------


# Will return a symlink path in its expanded form. If the path's root is the
# home directory symbol "~" then it'll be replaced by the full home path.
expand_path() {
    local ret="$1"

    IFS="/" read -ra parts <<< "$ret"
    if [[ "${parts[0]}" == "~" ]]; then
        ret="$HOME"
        for ((i=1; i < ${#parts[@]}; i++))
        do
            ret="$ret/${parts[$i]}"
        done
    fi
    ret=$(readlink -m "$ret")
    echo $ret
}

# Returned value does not have a trailing '\'.
unix_to_windows_path() {
    ret="$1"
    if [[ $(is_windows_path "$ret") -eq 0 ]]; then
        if [[ $(is_absolute_unix_path "$ret") -eq 1 ]]; then
            ret="${ret/\//}"
            # Fix the drive name, e.g. c\foo becomes c:\foo
            ret=$(sed 's,\([a-zA-Z]*\),\1:,' <<< "$ret")
        fi
        ret="${ret////\\}"    # Replace Unix slashes.
        ret="${ret//\\\(/\(}" # Remove backslash before (.
        ret="${ret//\\\)/\)}" # Remove backslash before ).
    fi

    # Strip trailing slashes.
    shopt -s extglob
    ret=$(echo "${ret%%+(\\)}")

    echo $ret
}

# Returned value does not have a trailing '/'.
windows_to_unix_path() {
    ret="$1"
    ret="/${ret/:/}"     # Remove drive ':'.
    ret="${ret//\\//}"   # Replace Windows slashes.
    ret="${ret// /\\ }"  # Add a backslash before spaces.
    ret="${ret//\(/\\(}" # Add a backslash before (.
    ret="${ret//\)/\\)}" # Add a backslash before ).

    # If the passed in path was a unix path then we'll have two leading '/'; strip if it exists.
    ret="${ret/\/\//\/}"

    # Strip trailing slashes.
    shopt -s extglob
    ret=$(echo "${ret%%+(/)}")

    echo "$ret"
}

# Returns a Unix path without escaped spaces, e.g. "/x/some folder" instead of "/x/some\ folder"
windows_to_unix_path_unescaped() {
    ret=$(windows_to_unix_path "$1")
    ret="${ret/\\ / }" # Remove '\' that appears before spaces.
    echo "$ret"
}

# Returns a Unix path with spaces escaped with a '\'.
escape_unix_path() {
    ret="$1"
    ret="${ret/ /\\ }"
    echo "$ret"
}

strip_path() {
    local result=$(basename "${1}")
    echo "$result"
}

strip_filename() {
    local result=$(dirname "${1}")
    echo "$result"
}

move_file() {
    local src="$1"
    local src_expanded=$(expand_path "$src")

    local dest_path=$(windows_to_unix_path_unescaped "$2")
    local dest_filename="$3"

    if [[ $dest_filename == "" ]]; then
        dest_filename=$(strip_path "$src")
    fi

    if [[ -e "$src_expanded" ]]; then
        mkdir -p "$dest_path"

        local dest="$dest_path/$dest_filename"
        mv "$src_expanded" "$dest"
        printf "${BOLD}${GREEN}==> ${NORMAL}Moved ${BOLD}${YELLOW}'$src'${NORMAL} to ${BOLD}${YELLOW}'$dest'${NORMAL}\n" 2>/dev/null
    else
        error "Unable to find $src_expanded!\n"
    fi
}

copy_file() {
    local src="$1"
    local src_expanded=$(expand_path "$src")

    local dest_path=$(windows_to_unix_path_unescaped "$2")
    local dest_filename="$3"

    if [[ $dest_filename == "" ]]; then
        dest_filename=$(strip_path "$src_expanded")
    fi

    if [[ -e "$src_expanded" ]]; then
        mkdir -p "$dest_path"

        local dest="$dest_path/$dest_filename"
        cp "$src_expanded" "$dest"
        printf "${BOLD}${GREEN}==> ${NORMAL}Copied ${BOLD}${YELLOW}'$src'${NORMAL} to ${BOLD}${YELLOW}'$dest'${NORMAL}\n" 2>/dev/null
    else
        error "Unable to find $src_expanded!\n"
    fi
}

copy_dir_files() {
    local src=$(expand_path "$1")
    local src_expanded=$(expand_path "$src")

    local dest_path=$(windows_to_unix_path_unescaped "$2")

    if [[ -d $src_expanded ]]; then
        mkdir -p $dest_path

        # Need to escape in order to use the wildcard and we have to eval in order to retain the backslash.
        local src_escaped=$(escape_unix_path "$src_expanded")
        cmd="cp -r $src_escaped/* \"$dest_path\""
        eval $cmd

        printf "${BOLD}${GREEN}==> ${NORMAL}Copied contents of ${BOLD}${YELLOW}'$src'${NORMAL} into ${BOLD}${YELLOW}'$dest_path'${NORMAL}\n" 2>/dev/null
    else
        error "Unable to find $src_expanded!\n"
    fi
}

is_absolute_unix_path() {
    if [[ $1 =~ ^/ ]]; then echo 1; else echo 0; fi
}

is_sym_file() {
    if [[ $1 =~ ^\.{1} ]]; then echo 1; else echo 0; fi
}

is_windows_path() {
    if [[ ! $1 =~ \/+ ]]; then echo 1; else echo 0; fi
}

is_unix_path() {
    echo $(! is_windows_path "$1")
}

path_has_a_space() {
    regexp="[[:blank:]]+"
    if [[ $1 =~ $regexp ]]; then echo 1; else echo 0; fi
}

# Expands a path when it's not a symbolic link or an absolute drive path.
clean_link_file_path() {
    path=$1
    if [[ $(is_absolute_unix_path "$path") -eq 0 && $(is_sym_file "$path") -eq 0 ]]; then
        path=$(expand_path "$path")
    fi
    echo $path
}

# Creates a symlink.
# Requires an admin shell when running under Windows.
link_file() {
    source_path=$1
    dest_path=$2
    require_confirmation=$3
    expand_symlinks=$4
    debug=0

    os_is_windows is_windows
    os_is_unix is_unix

    # @INSTEAD ESCAPE THE SPACES IN THE FINAL WINDOWS PATH:
    # e.g. path="${path// /\\ }" # Add a backslash before spaces.
    # https://stackoverflow.com/questions/1473981/how-to-check-if-a-string-has-spaces-in-bash-shell
    # https://stackoverflow.com/questions/28256178/how-can-i-match-spaces-with-a-regexp-in-bash

    source_has_space=$(path_has_a_space "$source_path")
    dest_has_space=$(path_has_a_space "$dest_path")

    if [[ $debug -eq 1 ]]; then
        echo source path: $source_path
        echo dest path: $dest_path
        echo source has space: $source_has_space
        echo dest has space: $dest_has_space
        echo abs unix source: $(is_absolute_unix_path "$source_path")
        echo abs unix dest: $(is_absolute_unix_path "$dest_path")
        echo "require_confirmation? $require_confirmation"
        echo "expand_symlinks? $expand_symlinks"
    fi

    if [[ $is_windows -eq 1 ]]; then
        if [[ $expand_symlinks -eq 1 ]]; then
            source_path=$(expand_path "$source_path")
            dest_path=$(expand_path "$dest_path")
        else
            source_path=$(clean_link_file_path "$source_path")
            dest_path=$(clean_link_file_path "$dest_path")
        fi
    fi

    if [[ $debug -eq 1 ]]; then
        echo "after source: $source_path"
        echo "after dest: $dest_path"
    fi

    # Verify that the source path exists.
    ! test -d "$source_path" && ! test -e "$source_path" && error "Source path '$source_path' doesn't exist!" && abort

    # Verify that the dest path doesn't already exist.
    test -d "$dest_path" && error "Dest folder '$dest_path' already exists!\n" && return
    test -e "$dest_path" && error "Dest file '$dest_path' already exists!\n" && return

    if [[ $is_windows -eq 1 ]]; then
        cmd_source_path=$(unix_to_windows_path "$source_path")
        cmd_dest_path=$(unix_to_windows_path "$dest_path")
        if [[ $source_has_space -eq 1 ]]; then cmd_source_path="\"$cmd_source_path\""; fi
        if [[ $dest_has_space -eq 1 ]];   then cmd_dest_path="\"$cmd_dest_path\""; fi
        link_cmd="cmd //c 'mklink $cmd_dest_path $cmd_source_path'"
    else
        if [[ $source_has_space -eq 1 ]]; then cmd_source_path="\"$cmd_source_path\""; fi
        if [[ $dest_has_space -eq 1 ]];   then cmd_dest_path="\"$cmd_dest_path\""; fi
        link_cmd="ln -sf $cmd_source_path $cmd_dest_path"
    fi

    if [[ $require_confirmation -eq 1 ]]; then
        echo "${BOLD}${BLUE}Will attempt to link ${YELLOW}$source_path${BLUE} to ${YELLOW}$dest_path${BLUE}"
        printf "${BOLD}Enter 1 to proceed\n${YELLOW}> ${NORMAL}"
        read confirm
        if [[ $confirm != 1 ]]; then abort; fi
    fi

    if [[ $debug -eq 1 ]]; then
        echo Final cmd source: $cmd_source_path
        echo Final cmd dest: $cmd_dest_path
        echo Link cmd:: $link_cmd
    fi

    printf "${BOLD}${GREEN}==> ${NORMAL}Linking ${BOLD}${YELLOW}'$source_path'${NORMAL} to ${BOLD}${YELLOW}'$dest_path'${NORMAL}\n" 2>/dev/null
    eval $link_cmd 1>/dev/null
}

setup_file() {
    src=$1
    dest=$2
    if [ ! -f $dest ]; then
        link_file $src $dest $confirm_link
    else
        printf "${BOLD}${MAGENTA}==> ${NORMAL}${BOLD}${YELLOW}'$dest'${NORMAL} already linked to ${BOLD}${YELLOW}'$src'${NORMAL}\n"
    fi
}

setup_dir() {
    src=$1
    dest=$2
    abort_if_src_not_found=$3

    if [ ! -d $src ]; then
        error "Source path '$src' doesn't exist!\n"
        if [[ $abort_if_src_not_found != "1" ]]; then
            abort
        else
            return
        fi
    fi
    if [ ! -d $dest ]; then
        link_file $src $dest $confirm_link
    else
        printf "${BOLD}${MAGENTA}==> ${NORMAL}${BOLD}${YELLOW}'$dest'${NORMAL} already linked to ${BOLD}${YELLOW}'$src'${NORMAL}\n"
    fi
}

create_dir() {
    path=$1
    if [ -d $path ]; then
        printf "${BOLD}${MAGENTA}==> ${NORMAL}${BOLD}${YELLOW}'$path'${NORMAL} already exists${NORMAL}\n"
        return
    fi
    mkdir $path
    printf "${BOLD}${GREEN}==> ${NORMAL}Created ${BOLD}${YELLOW}'$path'${NORMAL}\n"
}