state_machine.d2

direction: down

title: Payment Processing State Machine {
  near: top-center
  shape: text
  style.font-size: 22
  style.bold: true
}

flow: "" {
  direction: right
  style.fill: transparent
  style.stroke: transparent

  main: Happy Path {
    direction: down
    style.fill: "#eef6ff"
    style.stroke: "#6699cc"

    initiated: INITIATED {style.fill: "#ddeeff"}
    validating: VALIDATING {style.fill: "#ddeeff"}
    authorizing: AUTHORIZING {style.fill: "#FFD700"}
    capturing: CAPTURING {style.fill: "#FFD700"; style.bold: true}
    settled: SETTLED {style.fill: "#90EE90"; style.bold: true}
    refunded: REFUNDED {style.fill: "#cccccc"}

    initiated -> validating
    validating -> authorizing: payload ok
    authorizing -> capturing: auth ok
    capturing -> settled: capture ok
    settled -> refunded: refund initiated
  }

  exceptions: Exception Handling {
    direction: down
    style.fill: "#fde8e8"
    style.stroke: "#cc4444"

    validation_failed: VALIDATION FAILED {style.fill: "#FFB6C1"}
    auth_declined: AUTH DECLINED {style.fill: "#FFB6C1"}
    capture_failed: CAPTURE FAILED {style.fill: "#FFB6C1"}
    manual_review: MANUAL REVIEW {style.fill: "#ffcccc"; style.bold: true}

    validation_failed -> manual_review
    auth_declined -> manual_review
    capture_failed -> manual_review
  }
}

flow.main.validating -> flow.exceptions.validation_failed: invalid payload
flow.main.authorizing -> flow.exceptions.auth_declined: declined
flow.main.capturing -> flow.exceptions.capture_failed: gateway error
flow.exceptions.manual_review -> flow.main.initiated: retry approved
flow.main.refunded -> flow.main.initiated: refund completed