import * as Schema from "effect/Schema";
import * as VolumeTopology from "./VolumeTopology.generated.js";

export class VolumeTopologyRequirement extends Schema.Class<VolumeTopologyRequirement>("VolumeTopologyRequirement")(
    {
        // Requisite specifies a list of Topologies, at least one of which the
        // volume must be accessible from.
        //
        // Taken verbatim from the CSI Spec:
        //
        // Specifies the list of topologies the provisioned volume MUST be
        // accessible from.
        // This field is OPTIONAL. If TopologyRequirement is specified either
        // requisite or preferred or both MUST be specified.
        //
        // If requisite is specified, the provisioned volume MUST be
        // accessible from at least one of the requisite topologies.
        //
        // Given
        //   x = number of topologies provisioned volume is accessible from
        //   n = number of requisite topologies
        // The CO MUST ensure n >= 1. The SP MUST ensure x >= 1
        // If x==n, then the SP MUST make the provisioned volume available to
        // all topologies from the list of requisite topologies. If it is
        // unable to do so, the SP MUST fail the CreateVolume call.
        // For example, if a volume should be accessible from a single zone,
        // and requisite =
        //   {"region": "R1", "zone": "Z2"}
        // then the provisioned volume MUST be accessible from the "region"
        // "R1" and the "zone" "Z2".
        // Similarly, if a volume should be accessible from two zones, and
        // requisite =
        //   {"region": "R1", "zone": "Z2"},
        //   {"region": "R1", "zone": "Z3"}
        // then the provisioned volume MUST be accessible from the "region"
        // "R1" and both "zone" "Z2" and "zone" "Z3".
        //
        // If x<n, then the SP SHALL choose x unique topologies from the list
        // of requisite topologies. If it is unable to do so, the SP MUST fail
        // the CreateVolume call.
        // For example, if a volume should be accessible from a single zone,
        // and requisite =
        //   {"region": "R1", "zone": "Z2"},
        //   {"region": "R1", "zone": "Z3"}
        // then the SP may choose to make the provisioned volume available in
        // either the "zone" "Z2" or the "zone" "Z3" in the "region" "R1".
        // Similarly, if a volume should be accessible from two zones, and
        // requisite =
        //   {"region": "R1", "zone": "Z2"},
        //   {"region": "R1", "zone": "Z3"},
        //   {"region": "R1", "zone": "Z4"}
        // then the provisioned volume MUST be accessible from any combination
        // of two unique topologies: e.g. "R1/Z2" and "R1/Z3", or "R1/Z2" and
        //  "R1/Z4", or "R1/Z3" and "R1/Z4".
        //
        // If x>n, then the SP MUST make the provisioned volume available from
        // all topologies from the list of requisite topologies and MAY choose
        // the remaining x-n unique topologies from the list of all possible
        // topologies. If it is unable to do so, the SP MUST fail the
        // CreateVolume call.
        // For example, if a volume should be accessible from two zones, and
        // requisite =
        //   {"region": "R1", "zone": "Z2"}
        // then the provisioned volume MUST be accessible from the "region"
        // "R1" and the "zone" "Z2" and the SP may select the second zone
        // independently, e.g. "R1/Z4".
        Requisite: Schema.optionalWith(Schema.Array(Schema.NullOr(VolumeTopology.VolumeTopology)), {
            nullable: true,
        }),

        // Preferred is a list of Topologies that the volume should attempt to be
        // provisioned in.
        //
        // Taken from the CSI spec:
        //
        // Specifies the list of topologies the CO would prefer the volume to
        // be provisioned in.
        //
        // This field is OPTIONAL. If TopologyRequirement is specified either
        // requisite or preferred or both MUST be specified.
        //
        // An SP MUST attempt to make the provisioned volume available using
        // the preferred topologies in order from first to last.
        //
        // If requisite is specified, all topologies in preferred list MUST
        // also be present in the list of requisite topologies.
        //
        // If the SP is unable to make the provisioned volume available
        // from any of the preferred topologies, the SP MAY choose a topology
        // from the list of requisite topologies.
        // If the list of requisite topologies is not specified, then the SP
        // MAY choose from the list of all possible topologies.
        // If the list of requisite topologies is specified and the SP is
        // unable to make the provisioned volume available from any of the
        // requisite topologies it MUST fail the CreateVolume call.
        //
        // Example 1:
        // Given a volume should be accessible from a single zone, and
        // requisite =
        //   {"region": "R1", "zone": "Z2"},
        //   {"region": "R1", "zone": "Z3"}
        // preferred =
        //   {"region": "R1", "zone": "Z3"}
        // then the SP SHOULD first attempt to make the provisioned volume
        // available from "zone" "Z3" in the "region" "R1" and fall back to
        // "zone" "Z2" in the "region" "R1" if that is not possible.
        //
        // Example 2:
        // Given a volume should be accessible from a single zone, and
        // requisite =
        //   {"region": "R1", "zone": "Z2"},
        //   {"region": "R1", "zone": "Z3"},
        //   {"region": "R1", "zone": "Z4"},
        //   {"region": "R1", "zone": "Z5"}
        // preferred =
        //   {"region": "R1", "zone": "Z4"},
        //   {"region": "R1", "zone": "Z2"}
        // then the SP SHOULD first attempt to make the provisioned volume
        // accessible from "zone" "Z4" in the "region" "R1" and fall back to
        // "zone" "Z2" in the "region" "R1" if that is not possible. If that
        // is not possible, the SP may choose between either the "zone"
        // "Z3" or "Z5" in the "region" "R1".
        //
        // Example 3:
        // Given a volume should be accessible from TWO zones (because an
        // opaque parameter in CreateVolumeRequest, for example, specifies
        // the volume is accessible from two zones, aka synchronously
        // replicated), and
        // requisite =
        //   {"region": "R1", "zone": "Z2"},
        //   {"region": "R1", "zone": "Z3"},
        //   {"region": "R1", "zone": "Z4"},
        //   {"region": "R1", "zone": "Z5"}
        // preferred =
        //   {"region": "R1", "zone": "Z5"},
        //   {"region": "R1", "zone": "Z3"}
        // then the SP SHOULD first attempt to make the provisioned volume
        // accessible from the combination of the two "zones" "Z5" and "Z3" in
        // the "region" "R1". If that's not possible, it should fall back to
        // a combination of "Z5" and other possibilities from the list of
        // requisite. If that's not possible, it should fall back  to a
        // combination of "Z3" and other possibilities from the list of
        // requisite. If that's not possible, it should fall back  to a
        // combination of other possibilities from the list of requisite.
        Preferred: Schema.optionalWith(Schema.Array(Schema.NullOr(VolumeTopology.VolumeTopology)), {
            nullable: true,
        }),
    },
    {
        identifier: "VolumeTopologyRequirement",
        title: "volume.TopologyRequirement",
        documentation:
            "https://github.com/moby/moby/blob/a21b1a2d12e2c01542cb191eb526d7bfad0641e3/api/types/volume/cluster_volume.go#L158-L299",
    }
) {}