#!/usr/bin/env bash
# ~/.config/kitty/ssh_picker.sh
# Launched by kitty as an overlay window.
# Reads servers from ~/.ssh/config (Host entries) and lets
# you fuzzy-filter with arrow keys, then opens kitten ssh.
#
# Dependencies: none beyond bash + standard coreutils.
# Optional: fzf — if present it takes over the picker UI.

set -euo pipefail

# ------------------------------------------------------------
# config — edit these or let them fall through to ~/.ssh/config
# ------------------------------------------------------------
SSH_CONFIG="${HOME}/.ssh/config"
TERM_FALLBACK="xterm-256color"

# ------------------------------------------------------------
# gruvbox dark ANSI helpers
# ------------------------------------------------------------
RESET=$'\e[0m'
BOLD=$'\e[1m'
DIM=$'\e[2m'

GB_BG=$'\e[48;2;40;40;40m'          # #282828
GB_BG1=$'\e[48;2;60;56;54m'         # #3c3836
GB_BG2=$'\e[48;2;80;73;69m'         # #504945
GB_YELLOW=$'\e[38;2;250;189;47m'    # #fabd2f
GB_BLUE=$'\e[38;2;131;165;152m'     # #83a598
GB_GREEN=$'\e[38;2;184;187;38m'     # #b8bb26
GB_RED=$'\e[38;2;251;73;52m'        # #fb4934
GB_ORANGE=$'\e[38;2;254;128;25m'    # #fe8019
GB_FG=$'\e[38;2;235;219;178m'       # #ebdbb2
GB_DIM=$'\e[38;2;168;153;132m'      # #a89984

# ------------------------------------------------------------
# parse servers
# ------------------------------------------------------------
get_servers() {
    local servers=()

    # pull Host entries from ~/.ssh/config (skip wildcards)
    if [[ -f "$SSH_CONFIG" ]]; then
        while IFS= read -r line; do
            if [[ "$line" =~ ^[Hh]ost[[:space:]]+([^*?]+)$ ]]; then
                local host="${BASH_REMATCH[1]// /}"
                [[ -n "$host" ]] && servers+=("$host")
            fi
        done < "$SSH_CONFIG"
    fi

    # fallback examples if config is empty
    if [[ ${#servers[@]} -eq 0 ]]; then
        servers=(
            "contabo server"
            )
    fi

    printf '%s\n' "${servers[@]}"
}

# ------------------------------------------------------------
# fzf path (preferred)
# ------------------------------------------------------------
if command -v fzf &>/dev/null; then
    selected=$(get_servers | fzf \
        --prompt="  ssh  " \
        --pointer=">" \
        --marker="*" \
        --height=40% \
        --layout=reverse \
        --border=rounded \
        --info=inline \
        --color="dark,\
bg:#282828,\
bg+:#3c3836,\
fg:#ebdbb2,\
fg+:#fbf1c7,\
hl:#fabd2f,\
hl+:#fabd2f,\
border:#504945,\
prompt:#83a598,\
pointer:#fe8019,\
marker:#b8bb26,\
spinner:#d3869b,\
header:#a89984,\
info:#a89984" \
        --header="  ctrl+c to cancel" \
        --preview="echo {} | xargs -I% sh -c 'grep -A10 \"^Host %$\" ~/.ssh/config 2>/dev/null || echo \"no config entry\"'" \
        --preview-window="right:40%:wrap" \
        2>/dev/null) || exit 0

    [[ -z "$selected" ]] && exit 0
    TERM="$TERM_FALLBACK" kitten ssh "$selected"
    exit 0
fi

# ------------------------------------------------------------
# built-in picker (no fzf)
# ------------------------------------------------------------
mapfile -t SERVERS < <(get_servers)
TOTAL=${#SERVERS[@]}
SELECTED=0
QUERY=""
FILTERED=("${SERVERS[@]}")

draw() {
    clear
    printf '%s' "${GB_BG}"
    printf '\n'
    printf '  %s%s ssh picker%s\n' "${GB_YELLOW}${BOLD}" "" "${RESET}"
    printf '  %s%s%s\n\n' "${GB_DIM}" "arrow keys to navigate, enter to connect, esc to quit" "${RESET}"

    # search bar
    printf '  %ssearch:%s %s%s%s\n\n' \
        "${GB_DIM}" "${RESET}" \
        "${GB_FG}${BOLD}" "${QUERY}" "${RESET}"

    # server list
    local i=0
    for srv in "${FILTERED[@]}"; do
        if [[ $i -eq $SELECTED ]]; then
            printf '  %s%s > %s%s\n' "${GB_BG1}${GB_ORANGE}${BOLD}" "" "$srv" "${RESET}"
        else
            printf '  %s   %s%s\n' "${GB_DIM}" "$srv" "${RESET}"
        fi
        (( i++ ))
    done

    printf '\n  %s%s hosts found  •  install fzf for preview support%s\n' \
        "${GB_DIM}" "${#FILTERED[@]}" "${RESET}"
}

filter() {
    FILTERED=()
    SELECTED=0
    for srv in "${SERVERS[@]}"; do
        if [[ -z "$QUERY" || "${srv,,}" == *"${QUERY,,}"* ]]; then
            FILTERED+=("$srv")
        fi
    done
}

# hide cursor
tput civis
trap 'tput cnorm; clear' EXIT

while true; do
    draw

    # read a single keypress (handles escape sequences)
    IFS= read -r -s -N1 key

    # check for escape sequences (arrow keys)
    if [[ "$key" == $'\e' ]]; then
        IFS= read -r -s -N1 -t 0.1 k2 || true
        if [[ "$k2" == "[" ]]; then
            IFS= read -r -s -N1 -t 0.1 k3 || true
            case "$k3" in
                A)  # up
                    (( SELECTED > 0 )) && (( SELECTED-- ))
                    ;;
                B)  # down
                    (( SELECTED < ${#FILTERED[@]} - 1 )) && (( SELECTED++ ))
                    ;;
            esac
        else
            # plain escape — quit
            exit 0
        fi
        continue
    fi

    case "$key" in
        $'\n'|$'\r')
            [[ ${#FILTERED[@]} -eq 0 ]] && continue
            tput cnorm
            clear
            host="${FILTERED[$SELECTED]}"
            printf '%sconnecting to %s%s%s...\n\n' \
                "${GB_DIM}" "${GB_BLUE}${BOLD}" "$host" "${RESET}"
            TERM="$TERM_FALLBACK" kitten ssh "$host"
            exit 0
            ;;
        $'\x7f'|$'\b')
            # backspace
            QUERY="${QUERY%?}"
            filter
            ;;
        $'\x03')
            # ctrl+c
            exit 0
            ;;
        *)
            # printable character — append to query
            if [[ "$key" =~ ^[[:print:]]$ ]]; then
                QUERY+="$key"
                filter
            fi
            ;;
    esac
done