Automatically generate, send, and log customer invoices

flowchart TD trig>"order form submitted"]:::trig s0["generate invoice number"]:::task s1["check number is unique"]:::task s2["create PDF invoice"]:::task s3["distribute invoice"]:::task trig --> s0 s0 --> s1 s2 --> s3 gx{"+ where does invoice go"}:::gate s3 --> gx p00["send PDF by email"]:::task gx -->|"email customer"| p00 p10["save PDF to Drive"]:::task gx -->|"save file"| p10 p20["add row to sheet"]:::task gx -->|"log record"| p20 p00 --> out p10 --> out p20 --> out lp{"unique number generated"}:::gate s1 --> lp lp -. "number already in use" .-> s0 lp -->|"finished"| s2 out[/"invoice created and delivered"/]:::out pay{{"every order invoiced without manual work"}}:::pay out --> pay classDef task fill:#e7f6fe,stroke:#34b8f0,color:#2c2a29 classDef svc fill:#f6f8fa,stroke:#7c8795,color:#2c2a29 classDef mi fill:#e7f6fe,stroke:#0079a8,color:#2c2a29,stroke-width:2px classDef human fill:#fff,stroke:#0079a8,color:#0079a8 classDef store fill:#f6f8fa,stroke:#0079a8,color:#2c2a29 classDef trig fill:#00a4eb,stroke:#0079a8,color:#fff,font-weight:bold classDef trigtime fill:#00a4eb,stroke:#0079a8,color:#fff,font-weight:bold classDef trigdata fill:#8ad4f5,stroke:#0079a8,color:#06314c,font-weight:bold classDef gate fill:#fff,stroke:#e8a23d,color:#6b4708,font-weight:bold classDef out fill:#1f9d6b,stroke:#167a53,color:#fff,font-weight:bold classDef pay fill:#06314c,stroke:#021f33,color:#fff