{
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "$id": "https://spec-first.local/contracts/spec-work-run-state.schema.json",
  "title": "spec-work append-only run state snapshot",
  "type": "object",
  "additionalProperties": false,
  "required": [
    "schema_version",
    "generation",
    "previous_generation",
    "previous_sha256",
    "captured_at",
    "run_id",
    "worktree_identity",
    "units",
    "authorization",
    "collision",
    "recovery",
    "limitations"
  ],
  "properties": {
    "schema_version": {
      "const": "spec-work-run-state/v1"
    },
    "generation": {
      "type": "integer",
      "minimum": 1
    },
    "previous_generation": {
      "type": "integer",
      "minimum": 0
    },
    "previous_sha256": {
      "type": "string",
      "pattern": "^[a-f0-9]{64}$"
    },
    "captured_at": {
      "type": "string",
      "format": "date-time"
    },
    "run_id": {
      "type": "string",
      "pattern": "^[A-Za-z0-9][A-Za-z0-9._-]{0,80}$"
    },
    "worktree_identity": {
      "type": "object",
      "additionalProperties": false,
      "required": [
        "repo_root",
        "git_head",
        "dirty_fingerprint"
      ],
      "properties": {
        "repo_root": {
          "type": "string",
          "minLength": 1
        },
        "git_head": {
          "type": [
            "string",
            "null"
          ],
          "pattern": "^[a-f0-9]{40}$"
        },
        "dirty_fingerprint": {
          "type": "string",
          "pattern": "^[a-f0-9]{64}$"
        }
      }
    },
    "units": {
      "type": "array",
      "items": {
        "type": "object",
        "additionalProperties": false,
        "required": [
          "unit_id",
          "status",
          "requested_engine",
          "actual_engine",
          "authorization",
          "collision",
          "recovery",
          "verification"
        ],
        "properties": {
          "unit_id": {
            "type": "string",
            "pattern": "^[A-Za-z0-9][A-Za-z0-9._-]{0,80}$"
          },
          "status": {
            "enum": [
              "pending",
              "running",
              "passed",
              "failed",
              "blocked",
              "unknown"
            ]
          },
          "requested_engine": {
            "type": [
              "string",
              "null"
            ]
          },
          "actual_engine": {
            "type": [
              "string",
              "null"
            ]
          },
          "authorization": {
            "type": "object"
          },
          "collision": {
            "type": "object"
          },
          "recovery": {
            "type": "object"
          },
          "verification": {
            "type": "object",
            "additionalProperties": false,
            "required": [
              "status",
              "confirmed",
              "evidence_refs",
              "reason_code"
            ],
            "properties": {
              "status": {
                "enum": [
                  "not-started",
                  "started",
                  "passed",
                  "failed",
                  "unknown"
                ]
              },
              "confirmed": {
                "type": "boolean"
              },
              "evidence_refs": {
                "type": "array",
                "items": {
                  "type": "string"
                }
              },
              "reason_code": {
                "type": "string",
                "minLength": 1
              }
            }
          }
        }
      }
    },
    "authorization": {
      "type": "object"
    },
    "collision": {
      "type": "object"
    },
    "recovery": {
      "type": "object"
    },
    "limitations": {
      "type": "array",
      "items": {
        "type": "string"
      }
    }
  },
  "allOf": [
    {
      "if": {
        "properties": {
          "generation": {
            "const": 1
          }
        }
      },
      "then": {
        "properties": {
          "previous_generation": {
            "const": 0
          }
        }
      }
    }
  ]
}