#!/usr/bin/env bash
set -euo pipefail

ATTACH_TMUX=1
DRY_RUN=0
TMUX_SESSION_DEFAULT="default"

df_platform=""
df_namespace=""
df_user=""

ssh_identity=""
ssh_host=""
ssh_args=()

usage() {
    local prog
    prog=$(basename "$0")
    echo "Usage: $prog <platform> [user@]namespace [--no-tmux|-t] [--dry-run|-n] [-- <ssh args...>]" >&2
    echo
    echo "Examples:"
    echo "  $prog orb namespace"
    echo "  $prog utm user@namespace --no-tmux"
    echo "  $prog core user@namespace --dry-run -- -v -p 2222"
    exit 1
}

parse_args() {
    if [[ $# -lt 2 ]]; then
        usage
    fi

    df_platform="$1"
    local user_namespace_arg="$2"
    shift 2

    # Extract df_user and df_namespace
    if [[ "$user_namespace_arg" == *@* ]]; then
        df_user="${user_namespace_arg%@*}"
        df_namespace="${user_namespace_arg#*@}"
    else
        df_user="$USER"
        df_namespace="$user_namespace_arg"
    fi

    # Parse remaining flags and ssh args
    while [[ $# -gt 0 ]]; do
        case "$1" in
            -t|--no-tmux)
                ATTACH_TMUX=0
                shift
                ;;
            -n|--dry-run)
                DRY_RUN=1
                shift
                ;;
            --)
                shift
                ssh_args+=("$@")
                break
                ;;
            *)
                echo "Unknown option: $1" >&2
                usage
                ;;
        esac
    done
}

resolve_host() {
    case "$df_platform" in
        orb)
            # orb-stack handles user@namespace internally
            ssh_host="${df_namespace}@orb"
            ;;
        utm)
            ssh_host="${df_namespace}.utm.local"
            ssh_identity="$HOME/.ssh/id_ed25519_internal"
            ;;
        core)
            ssh_host="${df_namespace}.core.lan"
            ssh_identity="$HOME/.ssh/id_ed25519_internal"
            ;;
        ec2)
            ssh_host="${df_namespace}.ec2.internal"
            ;;
        hetzner)
            ssh_host="${df_namespace}.hetzner.test"
            ;;
        *)
            echo "Error: unknown platform '$df_platform'" >&2
            exit 1
            ;;
    esac
}

build_ssh_cmd() {
    local cmd=(ssh -tt)

    if [[ -n "$ssh_identity" ]]; then
        cmd+=(-i "$ssh_identity" -o IdentitiesOnly=yes)
    fi

    if [[ ${#ssh_args[@]} -gt 0 ]]; then
        cmd+=("${ssh_args[@]}")
    fi

    cmd+=("${df_user}@${ssh_host}")

    if [[ $ATTACH_TMUX -eq 1 ]]; then
        cmd+=("tmux" "new-session" "-As" "$TMUX_SESSION_DEFAULT"
              "-e" "DF_NAMESPACE=$df_namespace"
              "-e" "DF_PLATFORM=$df_platform")
    fi

    echo "${cmd[@]}"
}

main() {
    parse_args "$@"
    resolve_host
    ssh_cmd=($(build_ssh_cmd))

    if [[ $DRY_RUN -eq 1 ]]; then
        echo "Dry run command:"
        printf '%q ' "${ssh_cmd[@]}"
        echo
        exit 0
    fi

    exec "${ssh_cmd[@]}"
}

main "$@"