completion.mksh

# TODO:
#  - something is up with escaping/quoting and the glob to get candidates
#    ls Tournament\ Machu/test<__fzf_complete> -> nothing, should be test.txt^ntest2.txt
#  - ./ at beginning of line (i.e. for the first word)
#
# CASES:
#  - {unambig_complete, ambig_complete, no_complete}            x 
#    {start_of_word, middle_of_word, end_of_word, empty_word}   x
#    {first_word, middle_word, last_word}
#  - various numbers of spaces before and after the above cases
#  - spaces in various parts of input, as well as returned text
#  - "./" as first word (should match files, never commands)
#  - "$(" or "`" before cursor (should match commands, never files)
#  - other symbols: ', ", >, <, (, ), ./, shell syntax..., possibly &, etc.
#    - mksh's completion is kinda broken from within quotes...
#  - globbing -- handle it all!

fzf_mksh_abs="$(readlink -f $_)"
fzf_mksh_dir="$(dirname $fzf_mksh_abs)"
. "$fzf_mksh_dir/utils.mksh"
unset fzf_mksh_abs fzf_mksh_dir

function __fzf_get_completion_candidates {
    local args
    set -A args -- "$@"
    local matches
    # file completion
    if [ ${#args[@]} -gt 1 ]; then
        last_arg="${args[${#args[@]}-1]}"
        set +o markdirs
        if [[ $last_arg = *[*?]* ]]; then
            eval "set -A matches -- $last_arg"
        else
            set -A matches -- "$last_arg"*
        fi
        for match in "${matches[@]}"; do
            if [[ "${match}" != "$last_arg*" ]]; then
                if [[ -d "${match}" ]]; then
                    print -r -- "${match##*/}/"
                else
                    print -r -- "${match##*/}"
                fi
            fi
        done
    # command completion
    elif [ "${#args[@]}" -eq 1 ] || [ "${#args[@]}" -eq 0 ]; then
        local paths
        set -o noglob; IFS=:; set -A paths -- $PATH; IFS=$' \t\n'; set +o noglob
        for path in "${paths[@]}"; do
            matches+=(${path:-.}/"$@"*)
        done
        for match in "${matches[@]}"; do
            if [[ "${match##*/}" != "$@*" ]]; then
                print -r -- "${match##*/}"
            fi
        done | LC_ALL=C sort -u
    fi
}

function __fzf_complete {
    local comp
    local curr_0
    local curr_1
    local comp_y
    local comp_n
    set -A comp -- $1
    if [ "${1: -1}" = ' ' ]; then
        comp+=('')
    fi
    curr_0="$2"
    curr_1="$3"
    # comp_y is the current word post-completion
    comp_y="${comp[${#comp[@]}-1]}"
    # comp_n is the current word sans-completion
    comp_n="${curr_0}${curr_1}"
    if [ ${#comp_y} -ne ${#comp_n} ]; then
        print -r -- "$1
"
    else
        local sel
        local res
        local fzf_prompt_query_args
        fzf_prompt_query_args="--prompt=\"${FZF_COMPLETION_PROMPT_CHAR:->} $1\""
        sel=$(__fzf_get_completion_candidates "${comp[@]}")
        if [[ "$sel" = '' ]]; then
            print -rn -- "${1%${comp_y}}$2
$3"
        else
            local fzf_compl_args
            fzf_compl_args="--reverse --bind=ctrl-z:ignore --no-info -0 -1 +m"
            res=$(
                print -n "$sel" |
                    FZF_DEFAULT_OPTS="$FZF_DEFAULT_OPTS $fzf_compl_args $fzf_prompt_query_args" $(__fzf_cmd)
            )
            if [[ $res = *[![:space:]]* ]]; then
                print -rn -- "${1%${comp_y##*/}}$(__mksh_escape "$res")"
                if [[ ! "${res: -1}" = '/' ]]; then
                    print -rn -- ' '
                fi
            else
                print -rn -- "$1"
            fi
            print -r -- '
'
        fi
    fi
}

if [[ ! -o vi ]]; then
    # we need kill-region to be bound to something
    bind '^W'='kill-region'
    # '^v^a'                : special mark ^A
    # '^xD F^w^y ^y'    : move to left of mark, copy "current word, right of cursor", paste
    # '^x^x^xC^h'           : go back to beginning of word and delete the pasted special mark
    # '^x^xQ'             : quote the "current word, right of cursor" pasted text ($3)
    # '^v^b'                : special mark ^B
    # '^a'              : go back to the original cursor position (special mark ^A)
    # '^xC B^x^x^w^y'   : go to right of special mark, copy "current word, left of cursor, paste
    # '^xDF  ^y^hQ'   : paste a quoted copy of the "current word, left of cursor" ($2)
    # '^a^xC^h'     : go to original cursor position and try to complete
    # '^v^a'                : add the ^A mark we just deleted back; had to remove it to do completion
    # '^xDF '           : go to end of current word; if word was '', the ^A mark is necessary
    # '^a^xC^h^x^x '  : go back to the ^A mark, remove it, go back again, and set a mark
    # '^a^x^xQ'           : quote from the beginning of the line to the end of the current word ($1)
    # '^a __fzf_complete ': go to beginning of line, set a mark, type func name
    # '^b^xC^h^e'       : go back to ^B mark and delete it; evaluate
    # '^a^xC^h'         : __fzf_complete adds a mark indicating where the cursor needs to be
    bind -m '^I'='^v^a^xD F^w^y ^y^x^x^xC^h^x^xQ^v^b^a^xC B^x^x^w^y^xDF  ^y^hQ^a^xC^h^v^a^xDF ^a^xC^h^x^x ^a^x^xQ^a __fzf_complete ^b^xC^h^e^a^xC^h'
fi