# Shared config loading: how the config layers compose. Sourced, never executed.
# Precedence, weakest first:
#   defaults < versions.env < env.d/<profile> < <overlay>/rig.env < .env < caller's env.
# Run from ctrl/.
# Notes: docs/notes/config.md

# Per-invocation overrides: restored after the files are read, so the caller wins.
# NODES is deliberately not here (read from the kind config).
CONFIG_OVERRIDABLE="PROFILE OVERLAY CLUSTER K8S_VERSION KIND_CONFIG ADDONS
                    REGISTRY_MODE INGRESS_MODE DNS_MODE TILT_PORT
                    SOURCE ARCH DEPS_SOURCE HTTP_PORT HTTPS_PORT
                    REGISTRY_PORT MANIFESTS_DIR"

# rig's own example, used when no overlay is named (relative to rig's root).
DEFAULT_OVERLAY=examples/starter

# A rig-root-relative path as seen from ctrl/; absolute paths pass through.
_from_ctrl() { case "$1" in /*) echo "$1" ;; *) echo "../$1" ;; esac; }

# The same, absolute. Empty if it does not exist.
_abs_from_ctrl() { (cd "$(_from_ctrl "$1")" 2>/dev/null && pwd); }

# The environment's folder — the overlay's when one is named, else rig's —
# reduced to a DNS label kind accepts as a cluster name.
default_cluster_name() {
    local n
    if [ -n "${OVERLAY:-}" ]; then
        n=$(basename "$(_abs_from_ctrl "$OVERLAY_DIR")")
    else
        n=$(basename "$(cd .. && pwd)")
    fi
    n=$(echo "$n" | tr '[:upper:]' '[:lower:]' | tr -c 'a-z0-9-' '-')
    n=$(echo "$n" | sed 's/^-*//; s/-*$//')
    echo "${n:-rig}"
}

# Base of this environment's 10-port block; cksum so it is the same on every machine.
derive_port_base() {
    local h; h=$(printf '%s' "$1" | cksum | awk '{print $1}')
    echo $((20000 + (h % 200) * 10))
}

load_config() {
    local k saved=""
    for k in $CONFIG_OVERRIDABLE; do
        # ${!k+x} distinguishes "set but empty" from "unset" — an explicit
        # FOO= on the command line is a real choice and must survive.
        if [ -n "${!k+x}" ]; then
            saved+="$k=$(printf '%q' "${!k}")"$'\n'
        fi
    done

    set -a
    source ./versions.env
    # RIG_PORTABLE skips the machine-local .env (set by config_snapshot for kits).
    if [ -z "${RIG_PORTABLE:-}" ] && [ -f ./.env ]; then source ./.env; fi
    set +a

    # Re-apply overrides now so PROFILE is the caller's before we pick the file.
    _config_restore "$saved"

    # A profile is optional; naming one that does not exist is an error.
    local profile="${PROFILE:-}" layered=""
    if [ -n "$profile" ] && [ "$profile" != default ]; then
        if [ ! -f "./env.d/${profile}.env" ]; then
            echo "no such profile: env.d/${profile}.env" >&2
            if [ -d "../examples/${profile}" ]; then
                echo "  it is an example overlay now: OVERLAY=examples/${profile}" >&2
            fi
            echo "available: $(config_profiles | tr '\n' ' ')" >&2
            exit 1
        fi
        set -a
        source "./env.d/${profile}.env"
        set +a
        layered=1
    fi

    # The overlay: one folder, outside rig, holding a use case (docs/notes/overlay.md).
    # Named ones must exist; with none named, rig's own example is used if present.
    OVERLAY_DIR=""
    if [ -n "${OVERLAY:-}" ]; then
        OVERLAY_DIR="${OVERLAY%/}"
        if [ ! -d "$(_from_ctrl "$OVERLAY_DIR")" ]; then
            echo "no overlay at OVERLAY=${OVERLAY} (relative to rig's folder, or absolute)" >&2
            exit 1
        fi
    elif [ -d "../${DEFAULT_OVERLAY}" ]; then
        OVERLAY_DIR="$DEFAULT_OVERLAY"
    fi
    # Its rig.env may not choose the profile or the overlay (both are chosen before
    # it loads), and the paths it sets are relative to the overlay.
    local ov_env="" m_before k_before
    if [ -n "$OVERLAY_DIR" ]; then ov_env="$(_from_ctrl "$OVERLAY_DIR")/rig.env"; fi
    if [ -n "$ov_env" ] && [ -f "$ov_env" ]; then
        if grep -qE '^[[:space:]]*(export[[:space:]]+)?(PROFILE|OVERLAY)=' "$ov_env"; then
            echo "$ov_env: an overlay's rig.env cannot set PROFILE or OVERLAY (they choose it)" >&2
            exit 1
        fi
        m_before="${MANIFESTS_DIR-}" k_before="${KIND_CONFIG-}"
        set -a
        source "$ov_env"
        set +a
        if [ "${MANIFESTS_DIR-}" != "$m_before" ]; then
            case "$MANIFESTS_DIR" in /*|none|"") ;; *) MANIFESTS_DIR="${OVERLAY_DIR}/${MANIFESTS_DIR}" ;; esac
        fi
        if [ "${KIND_CONFIG-}" != "$k_before" ]; then
            case "$KIND_CONFIG" in /*|"") ;; *) KIND_CONFIG="$(dirname "$ov_env")/${KIND_CONFIG}" ;; esac
        fi
        layered=1
    fi

    # The machine and the caller still win over both.
    if [ -n "$layered" ]; then
        set -a
        if [ -z "${RIG_PORTABLE:-}" ] && [ -f ./.env ]; then source ./.env; fi
        set +a
        _config_restore "$saved"
    fi

    # The defaults a profile would otherwise have to supply. Weakest of all: a
    # profile, ctrl/.env and the caller each override them.
    PROFILE_NAME="${PROFILE_NAME:-default}"
    ADDONS="${ADDONS-}"
    # local, not none: with no registry an unqualified image name means
    # docker.io/library/<name>, and a default must not make that disclosure.
    REGISTRY_MODE="${REGISTRY_MODE:-local}"
    INGRESS_MODE="${INGRESS_MODE:-hostport}"
    DNS_MODE="${DNS_MODE:-hosts}"
    # The newest node image versions.env pins, found rather than restated, so
    # bumping the pins moves the default with them.
    if [ -z "${K8S_VERSION:-}" ]; then
        K8S_VERSION=$(compgen -v NODE_IMAGE_v | sort -V | tail -1)
        K8S_VERSION="${K8S_VERSION#NODE_IMAGE_}"
    fi

    # Identity follows the folder, so a renamed copy is a distinct environment.
    CLUSTER="${CLUSTER:-$(default_cluster_name)}"
    KUBECONTEXT="kind-${CLUSTER}"

    # Host ports: fill only the gaps from the derived block; anything already set wins.
    local base; base=$(derive_port_base "$CLUSTER")
    HTTP_PORT="${HTTP_PORT:-$base}"
    HTTPS_PORT="${HTTPS_PORT:-$((base + 1))}"
    TILT_PORT="${TILT_PORT:-$((base + 2))}"
    REGISTRY_PORT="${REGISTRY_PORT:-$((base + 3))}"

    # Where the workload's manifests live, relative to rig's folder (or absolute):
    # the overlay's k8s/overlays/dev unless something names another. `none`: rig
    # applies none (the overlay's Tiltfile does). A named folder must exist.
    if [ "${MANIFESTS_DIR:-}" = ctrl/k8s/overlays/dev ] && [ ! -d ../ctrl/k8s/overlays/dev ]; then
        # The old default, pinned by an older .env.example; rig's examples moved.
        STALE_MANIFESTS_DIR="$MANIFESTS_DIR"
        MANIFESTS_DIR=""
    fi
    if [ -z "${MANIFESTS_DIR:-}" ] && [ -n "$OVERLAY_DIR" ] \
       && [ -d "$(_from_ctrl "$OVERLAY_DIR")/k8s/overlays/dev" ]; then
        MANIFESTS_DIR="$OVERLAY_DIR/k8s/overlays/dev"
    fi
    MANIFESTS_DIR="${MANIFESTS_DIR:-}"
    if [ "$MANIFESTS_DIR" = none ]; then
        MANIFESTS_DIR=""
    elif [ -n "$MANIFESTS_DIR" ] && [ ! -d "$(_from_ctrl "$MANIFESTS_DIR")" ]; then
        echo "no manifests at MANIFESTS_DIR=${MANIFESTS_DIR} (relative to rig's folder, or absolute)" >&2
        exit 1
    fi

    # Profiles name a k8s minor (v1_36); versions.env holds the pinned digest.
    local var="NODE_IMAGE_${K8S_VERSION}"
    NODE_IMAGE="${!var:-}"
    if [ -z "$NODE_IMAGE" ]; then
        echo "K8S_VERSION='${K8S_VERSION}' has no NODE_IMAGE_${K8S_VERSION} in versions.env" >&2
        exit 1
    fi

    # The cluster is one file: the overlay's kind-config.yaml.tpl if it has one,
    # else rig's k8s/kind-config.yaml.tpl. KIND_CONFIG is "use this file instead",
    # for a project that builds its own cluster through rig (relative to ctrl/, or absolute).
    if [ -z "${KIND_CONFIG:-}" ] && [ -n "$OVERLAY_DIR" ] \
       && [ -f "$(_from_ctrl "$OVERLAY_DIR")/kind-config.yaml.tpl" ]; then
        KIND_CONFIG="$(_from_ctrl "$OVERLAY_DIR")/kind-config.yaml.tpl"
    fi
    KIND_CONFIG="${KIND_CONFIG:-./k8s/kind-config.yaml.tpl}"
    if [ ! -f "$KIND_CONFIG" ]; then
        echo "no kind config at KIND_CONFIG=${KIND_CONFIG}" >&2
        exit 1
    fi

    # Read the node count back out of the file rather than restating it:
    # check.sh and the memory tool size their budget on NODES.
    NODES=$(grep -c '^  - role:' "$KIND_CONFIG")

    # Measured MB per node (cluster alone, errs high for workers); shared by
    # check.sh, the memory tool and standalone kits.
    NODE_MB=800
}

# Render the kind config to stdout with sed (not envsubst) over an explicit variable list.
# HOST_WORKDIR and OVERLAY_DIR must be host paths: the host dockerd resolves hostPath entries.
render_kind_config() {
    local host_workdir="${HOST_WORKDIR:-$(cd .. && pwd)}" overlay_dir=""
    if [ -n "$OVERLAY_DIR" ]; then overlay_dir=$(_abs_from_ctrl "$OVERLAY_DIR"); fi
    sed -e "s|\${CLUSTER}|${CLUSTER}|g" \
        -e "s|\${NODE_IMAGE}|${NODE_IMAGE}|g" \
        -e "s|\${HTTP_PORT}|${HTTP_PORT}|g" \
        -e "s|\${HOST_WORKDIR}|${host_workdir}|g" \
        -e "s|\${OVERLAY_DIR}|${overlay_dir}|g" \
        "$KIND_CONFIG"
}

_config_restore() {
    local line
    while IFS= read -r line; do
        if [ -n "$line" ]; then
            eval "export $line"
        fi
    done <<< "$1"
    # A while loop returns its last body command's status; the trailing empty
    # line would otherwise make this return 1 and trip `set -e` in the caller.
    return 0
}

# ── what a standalone kit needs to know ────────────────────────────────────
# The questions ctrl/standalone.sh asks, so it never knows how config is stored.

# Every configuration rig can run as, one per line: each profile, or `default`
# when there are none. Never empty.
config_profiles() {
    local f found=""
    for f in ./env.d/*.env; do
        [ -e "$f" ] || continue
        f=${f##*/}; echo "${f%.env}"; found=1
    done
    [ -n "$found" ] || echo default
}

# What load_config sets, minus the machine-local layer, as `declare -p` lines.
# Usage: config_snapshot <profile> | --current   (found by difference, not a list)
config_snapshot() {
    local _rig_snap_choices
    if [ "$1" = --current ]; then
        _rig_snap_choices=$( (
            load_config >/dev/null || exit 1
            for _rig_snap_n in $CONFIG_OVERRIDABLE; do
                if [ -n "${!_rig_snap_n+x}" ]; then printf 'export %s=%q\n' "$_rig_snap_n" "${!_rig_snap_n}"; fi
            done
        ) ) || return 1
    else
        _rig_snap_choices="export PROFILE=$(printf '%q' "$1")"
    fi
    (
        # Nothing from the caller's shell may leak into a kit.
        for _rig_snap_n in $CONFIG_OVERRIDABLE; do unset "$_rig_snap_n"; done
        declare -A _rig_snap_was=()
        for _rig_snap_n in $(compgen -v); do
            _rig_snap_was[$_rig_snap_n]="${!_rig_snap_n-}"
        done
        eval "$_rig_snap_choices"
        RIG_PORTABLE=1 load_config >/dev/null
        for _rig_snap_n in $(compgen -v); do
            case "$_rig_snap_n" in
                _rig_snap_*|RIG_PORTABLE|BASH*|FUNCNAME|PIPESTATUS|LINENO|RANDOM|SRANDOM|\
                SECONDS|EPOCH*|HISTCMD|COLUMNS|LINES|PWD|OLDPWD|_|SHLVL|OPTIND|OPTERR) continue ;;
            esac
            if [ -z "${_rig_snap_was[$_rig_snap_n]+x}" ] \
               || [ "${_rig_snap_was[$_rig_snap_n]}" != "${!_rig_snap_n-}" ]; then
                declare -p "$_rig_snap_n"
            fi
        done
    )
}

# The profile this machine runs, as load_config resolves it here.
config_current_profile() { ( load_config >/dev/null && echo "$PROFILE_NAME" ); }

# Names (never values) of .env keys an export does not carry, e.g. credentials.
config_left_out() {
    [ -f ./.env ] || return 0
    local k
    for k in $(sed -nE 's/^[[:space:]]*(export[[:space:]]+)?([A-Za-z_][A-Za-z0-9_]*)=.*/\2/p' ./.env | sort -u); do
        case " $(echo $CONFIG_OVERRIDABLE) " in
            *" $k "*) ;;
            *) echo "$k" ;;
        esac
    done
}

# Print a load_config with a resolution frozen in, for a standalone kit to carry.
# The caller's env still wins; derived values (e.g. ports) stay fixed.
config_freeze() {
    local snap
    snap=$(config_snapshot "$1") || return 1
    cat <<'EOF'
load_config() {
    local k saved=""
    for k in $CONFIG_OVERRIDABLE; do
        if [ -n "${!k+x}" ]; then saved+="$k=$(printf '%q' "${!k}")"$'\n'; fi
    done
EOF
    printf '%s\n' "$snap" | sed -E 's/^declare --* /    declare -g /; s/^declare -([a-zA-Z]+) /    declare -g\1 /'
    cat <<'EOF'
    _config_restore "$saved"
}
EOF
}