{
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "$id": "https://buildchain.libkungfu.dev/schema/v4-stage-capsule-resume-v1.schema.json",
  "title": "Buildchain v4 Stage Capsule resume planner contract suite",
  "description": "Closed pure request and plan contracts for deterministic Stage Capsule resume decisions.",
  "type": "object",
  "additionalProperties": false,
  "required": ["schemaVersion", "request", "plan"],
  "properties": {
    "schemaVersion": { "const": 1 },
    "request": { "$ref": "#/$defs/request" },
    "plan": { "$ref": "#/$defs/plan" }
  },
  "$defs": {
    "root": {
      "type": "string",
      "pattern": "^sha256:[0-9a-f]{64}$"
    },
    "clock": {
      "type": "string",
      "pattern": "^(?!0000)\\d{4}-\\d{2}-\\d{2}T\\d{2}:\\d{2}:\\d{2}\\.\\d{3}Z$"
    },
    "token": {
      "type": "string",
      "pattern": "^[a-z][a-z0-9]*(?:-[a-z0-9]+)*$"
    },
    "retentionPromise": {
      "type": "object",
      "additionalProperties": false,
      "required": ["class", "retainUntil"],
      "properties": {
        "class": { "$ref": "#/$defs/token" },
        "retainUntil": { "$ref": "#/$defs/clock" }
      }
    },
    "candidate": {
      "type": ["object", "null"],
      "additionalProperties": false,
      "required": ["capsule", "availability"],
      "properties": {
        "capsule": {
          "$ref": "v4-stage-capsule-v1.schema.json#/$defs/capsule"
        },
        "availability": {
          "$ref": "v4-stage-capsule-v1.schema.json#/$defs/availability"
        }
      }
    },
    "node": {
      "type": "object",
      "additionalProperties": false,
      "required": [
        "key",
        "dependencies",
        "expectedIdentity",
        "expectedRetentionPromise",
        "candidate"
      ],
      "properties": {
        "key": { "$ref": "#/$defs/token" },
        "dependencies": {
          "type": "array",
          "uniqueItems": true,
          "items": { "$ref": "#/$defs/token" }
        },
        "expectedIdentity": {
          "$ref": "v4-stage-capsule-v1.schema.json#/$defs/identity"
        },
        "expectedRetentionPromise": {
          "$ref": "#/$defs/retentionPromise"
        },
        "candidate": { "$ref": "#/$defs/candidate" }
      }
    },
    "effect": {
      "type": "object",
      "additionalProperties": false,
      "required": [
        "id",
        "kind",
        "provider",
        "afterStages",
        "providerReadback",
        "mutation"
      ],
      "properties": {
        "id": { "$ref": "#/$defs/token" },
        "kind": { "$ref": "#/$defs/token" },
        "provider": { "$ref": "#/$defs/token" },
        "afterStages": {
          "type": "array",
          "uniqueItems": true,
          "items": { "$ref": "#/$defs/token" }
        },
        "providerReadback": { "const": true },
        "mutation": { "const": false }
      }
    },
    "request": {
      "type": "object",
      "additionalProperties": false,
      "required": ["schema", "evaluatedAt", "nodes", "targets", "effects"],
      "properties": {
        "schema": {
          "const": "buildchain-v4-stage-capsule-resume-request/v1"
        },
        "evaluatedAt": { "$ref": "#/$defs/clock" },
        "nodes": {
          "type": "array",
          "minItems": 1,
          "items": { "$ref": "#/$defs/node" }
        },
        "targets": {
          "type": "array",
          "minItems": 1,
          "uniqueItems": true,
          "items": { "$ref": "#/$defs/token" }
        },
        "effects": {
          "type": "array",
          "items": { "$ref": "#/$defs/effect" }
        }
      }
    },
    "cause": {
      "type": "object",
      "additionalProperties": false,
      "required": ["field", "expectedRoot", "observedRoot"],
      "properties": {
        "field": { "$ref": "#/$defs/token" },
        "expectedRoot": { "$ref": "#/$defs/root" },
        "observedRoot": { "$ref": "#/$defs/root" }
      }
    },
    "read": {
      "type": "object",
      "additionalProperties": false,
      "required": ["kind", "name", "root"],
      "properties": {
        "kind": { "$ref": "#/$defs/token" },
        "name": { "$ref": "#/$defs/token" },
        "root": { "$ref": "#/$defs/root" }
      }
    },
    "decision": {
      "type": "object",
      "additionalProperties": false,
      "required": [
        "stageKey",
        "platform",
        "stage",
        "decision",
        "execution",
        "reasonCode",
        "capsuleRoot",
        "availabilityRoot",
        "invalidationCauses",
        "requiredReads"
      ],
      "properties": {
        "stageKey": { "$ref": "#/$defs/token" },
        "platform": { "$ref": "#/$defs/token" },
        "stage": { "$ref": "#/$defs/token" },
        "decision": { "enum": ["reuse", "rebuild", "reject"] },
        "execution": { "enum": ["reuse", "rebuild"] },
        "reasonCode": { "$ref": "#/$defs/token" },
        "capsuleRoot": {
          "anyOf": [{ "$ref": "#/$defs/root" }, { "type": "null" }]
        },
        "availabilityRoot": {
          "anyOf": [{ "$ref": "#/$defs/root" }, { "type": "null" }]
        },
        "invalidationCauses": {
          "type": "array",
          "items": { "$ref": "#/$defs/cause" }
        },
        "requiredReads": {
          "type": "array",
          "items": { "$ref": "#/$defs/read" }
        }
      }
    },
    "plan": {
      "type": "object",
      "additionalProperties": false,
      "required": [
        "schema",
        "mode",
        "productionAuthority",
        "evaluatedAt",
        "decisions",
        "requiredRestores",
        "requiredStages",
        "requiredEffects",
        "planRoot"
      ],
      "properties": {
        "schema": { "const": "buildchain-v4-stage-capsule-resume-plan/v1" },
        "mode": { "const": "shadow-only" },
        "productionAuthority": { "const": "v3" },
        "evaluatedAt": { "$ref": "#/$defs/clock" },
        "decisions": {
          "type": "array",
          "minItems": 1,
          "items": { "$ref": "#/$defs/decision" }
        },
        "requiredRestores": {
          "type": "array",
          "uniqueItems": true,
          "items": { "$ref": "#/$defs/token" }
        },
        "requiredStages": {
          "type": "array",
          "uniqueItems": true,
          "items": { "$ref": "#/$defs/token" }
        },
        "requiredEffects": {
          "type": "array",
          "items": { "$ref": "#/$defs/effect" }
        },
        "planRoot": { "$ref": "#/$defs/root" }
      }
    }
  }
}