#!/bin/bash
set -euo pipefail

# Used to make sure PersistantVolumes don't clash with one another
NORMALIZE_PATTERN='s|/|-|g;s|--|-|g'


log () {
    echo "$@" | ts >&2
}


[ ! -f "${STATEFILE}" ] && touch "${STATEFILE}"


pending_volumes="$(kubectl get -A persistentvolumeclaims -o json | jq '.items[] | select(.spec.storageClassName=="iscsi" and .status.phase=="Pending" and .spec.volumeName==null)')"

for claim in $(echo "${pending_volumes}" | jq -r '. | .metadata.namespace + "/" + .metadata.name'); do \
    namespace="$(echo "${claim}" | cut -d/ -f1)"
    name="$(echo "${claim}" | cut -d/ -f2)"
    
    manifest="$(echo "${pending_volumes}" | jq '. | select(.metadata.namespace=="'"${namespace}"'" and .metadata.name=="'"${name}"'")')"
    requested_size="$(echo "${manifest}" | jq -r .spec.resources.requests.storage)"
    filesystem="$(echo "${manifest}" | jq -er '.metadata.annotations."iscsi-provisioner/filesystem"')" || filesystem="${FILESYSTEM}"

    blockname="$(echo "${namespace}" | sed -E "${NORMALIZE_PATTERN}")--$(echo "${name}" | sed -E "${NORMALIZE_PATTERN}")"
    lvname="iscsi--${blockname}"

    log "Found pending persistent volume claim '${name}' for ${requested_size} in namespace '${namespace}'"

    if ! sudo lvs "${LVM_GROUP}/${lvname}" > /dev/null 2>&1; then \
        if [ -z "${notdef:-}" ]; then \
            sudo lvcreate -W -L "${requested_size}" -n "${lvname}" "${LVM_GROUP}"
        else
            sudo lvcreate -V "${requested_size}" -n "${lvname}" -T "${LVM_GROUP}/${LV_THIN_POOL}"
        fi
        log "Created new logical volume '${LVM_GROUP}/${lvname}'"
    fi

    if ! grep -xnF -- "${blockname}" "${STATEFILE}" > /dev/null 2>&1; then \
        echo "${blockname}" >> ${STATEFILE}
    fi
    lun="$(grep -xnF -- "${blockname}" "${STATEFILE}" | cut -d: -f1)"

    if ! sudo targetcli /backstores/block ls "${blockname}" >/dev/null 2>&1; then
        sudo targetcli /backstores/block create "${blockname}" "/dev/${LVM_GROUP}/${lvname}"
        log "Created new backing block storage volume '${blockname}' -> '/dev/${LVM_GROUP}/${lvname}'"
    fi

    if ! sudo targetcli /iscsi/$IQN/tpg1/luns ls "lun${lun}" >/dev/null 2>&1; then
        sudo targetcli /iscsi/$IQN/tpg1/luns create "/backstores/block/${blockname}" "${lun}"
        log "Added LUN ${lun} to '/iscsi/$IQN/tpg1'"
    fi

    kubectl apply --field-manager iscsi-provisioner --server-side -f - <<EOF
apiVersion: v1
kind: PersistentVolume
metadata:
    name: '${blockname}'
spec:
    capacity:
        storage: '${requested_size}'
    accessModes:
        - ReadWriteOnce
    claimRef:
        namespace: '${namespace}'
        name: '${name}'
    storageClassName: iscsi
    iscsi:
        targetPortal: '${PORTAL_ADDR}'
        iqn: '${IQN}'
        lun: ${lun}
        fsType: ext4
        readOnly: false
EOF
done