digraph list {
    node [shape="rectangle"];

    list [label="Command: list", shape="oval", style="filled", fillcolor="lightblue"];
    get_all [label="Get all\navailable versions"];
    full_list [label="Full list", style="filled", fillcolor="lightsalmon"];

    subgraph cluster_get_all {
        label = "Installed toolchains";
        style = "filled";
        shape = "rectangle";

        get_from_installed [label="Get installed version"];
        installed_list [label="Installed list", shape="hexagon"];
    }

    subgraph cluster_get_file {
        label = "From .python-version";
        style = "filled";
        shape = "rectangle";

        get_from_file [label="Get version\nfrom .python-version"];

        file_exists [label=".python-version exists?", shape="diamond"];
        load_file [label="Load .python-version"];

        decision_path_or_version [label="Path or Version?", shape="diamond"];

        loaded_path [label="Path"];
        loaded_version [label="Version"];

        normalize_path [label="Normalize path"];
        path_exists [label="Path exists?", shape="diamond"];
        path_is_python [label="Path is\nPython path?", shape="diamond"];
        get_version_from_path [label="Get Version\nfrom executable"];
        combined_version_path [label="Path+Version"];
        decision_is_installed [label="Is installed?", shape="diamond"];

        subgraph cluster_versions {
            color = "none";
            label = "";
            installed_toolchain [label="Installed toolchain\n(Version, Path)"];
            not_installed_toolchain_version [label="Not Installed toolchain\n(Version)"];
            not_installed_toolchain_path [label="Not Installed toolchain\n(Path)"];
        }

        selected_toolchain [label="Selected toolchain", shape="hexagon"];
    }

    // ========================================================
    // Transitions

    list -> get_all;
    get_all -> get_from_file;
    get_all -> get_from_installed;

    get_from_installed -> installed_list;

    get_from_file -> file_exists;
    file_exists -> load_file [label="Yes"];
    load_file -> decision_path_or_version;
    decision_path_or_version -> loaded_path;
    decision_path_or_version -> loaded_version;

    loaded_path -> normalize_path;
    normalize_path -> path_exists;
    path_exists -> path_is_python [label="Yes"];
    path_exists -> not_installed_toolchain_path [label="No"];

    path_is_python -> get_version_from_path [label="Yes"];
    path_is_python -> not_installed_toolchain_path [label="No"];

    get_version_from_path -> combined_version_path;

    combined_version_path -> installed_toolchain;

    loaded_version -> decision_is_installed;
    installed_list -> decision_is_installed;

    decision_is_installed -> installed_toolchain [label="Yes"];
    decision_is_installed -> not_installed_toolchain_version [label="No"];

    not_installed_toolchain_version -> selected_toolchain;
    not_installed_toolchain_path -> selected_toolchain;
    installed_toolchain -> selected_toolchain;
    installed_list -> full_list;
    selected_toolchain -> full_list;
}