datasource db {
  provider = "postgresql"
  url      = env("DATABASE_URL")
}

generator client {
  provider = "prisma-client-js"
}

model Venue {
  id        String   @id @default(uuid())
  name      String
  createdAt DateTime @default(now())
  updatedAt DateTime @updatedAt

  devices          Device[]
  clientUsers      ClientUser[]
  remoteCommands   RemoteCommand[]
  auditLogs        AuditLog[]
  regCodes         RegistrationCode[]
  plannedTabs      PlannedTab[]
  tabReminders     TabReminder[]
  tabEvents        TabEvent[]
  products         Product[]
  stockAdjustments StockAdjustment[]
  tabs             Tab[]
  settlements      Settlement[]
  // Set on the first sync after the server started holding the tabs: the tabs were then taken over from the
  // terminal's own open tabs, once
  tabsSeededAt     DateTime?
}

model Device {
  id             String    @id @default(uuid())
  // A venue can have several terminals
  venueId        String
  name           String
  tokenHash      String    @unique
  tokenPrefix    String
  tokenExpiresAt DateTime
  lastSeenAt     DateTime  @default(now())
  revokedAt      DateTime?
  createdAt      DateTime  @default(now())

  venue          Venue           @relation(fields: [venueId], references: [id])
  remoteCommands RemoteCommand[]
  tabEvents      TabEvent[]
  settlements    Settlement[]

  @@index([venueId, revokedAt])
}

model ClientUser {
  id           String   @id @default(uuid())
  venueId      String
  email        String   @unique
  passwordHash String
  name         String
  // admin (the owner: users and terminals) | manager (runs the venue: products, stock, tabs, reminders) |
  // superadmin (runs KoolTap itself: every venue, and the admin page)
  role         String   @default("manager")
  createdAt    DateTime @default(now())
  // Access tokens issued before this are refused, so a forced logout applies at once instead of when they expire
  sessionsRevokedAt DateTime?

  venue Venue @relation(fields: [venueId], references: [id])

  @@index([venueId])
}

model RegistrationCode {
  id        String    @id @default(uuid())
  venueId   String
  code      String    @unique
  expiresAt DateTime
  usedAt    DateTime?
  createdAt DateTime  @default(now())

  venue Venue @relation(fields: [venueId], references: [id])

  @@index([venueId])
}

// A request from the dashboard. close_tab used to be executed by the owning terminal; the server now settles
// the tab itself and records the command as completed right away, for the history.
model RemoteCommand {
  id              String    @id @default(uuid())
  venueId         String
  // Null for a command the server carried out itself
  deviceId        String?
  targetTabId     String
  customerName    String?
  amountInCents   Int?
  type            String    @default("close_tab")
  expectedVersion Int
  paymentMethod   String
  requestedBy     String
  status          String    @default("pending")
  result          String?
  acknowledgedAt  DateTime?
  createdAt       DateTime  @default(now())
  expiresAt       DateTime

  venue  Venue   @relation(fields: [venueId], references: [id])
  device Device? @relation(fields: [deviceId], references: [id])

  @@index([deviceId, status, createdAt])
  @@index([venueId, status, createdAt])
}

model AuditLog {
  id        String   @id @default(uuid())
  venueId   String
  actorType String
  actorId   String
  action    String
  details   String?
  createdAt DateTime @default(now())

  venue Venue @relation(fields: [venueId], references: [id])

  @@index([venueId, createdAt])
}

model RefreshToken {
  id        String    @id @default(uuid())
  userId    String
  tokenHash String    @unique
  expiresAt DateTime
  revokedAt DateTime?
  createdAt DateTime  @default(now())

  @@index([userId])
}

model PlannedTab {
  id              String    @id @default(uuid())
  venueId         String
  customerName    String
  // Lowercased, whitespace-collapsed name: customers are matched on this everywhere
  customerNameKey String
  email           String?
  position        Int       @default(0)
  createdAt       DateTime  @default(now())
  // Set once the terminal reports an open tab with this name; it is then no longer sent to devices
  deliveredAt     DateTime?

  venue Venue @relation(fields: [venueId], references: [id])

  @@unique([venueId, customerNameKey])
  @@index([venueId])
}

model TabReminder {
  id            String   @id @default(uuid())
  venueId       String
  tabId         String
  customerName  String
  email         String
  amountInCents Int
  sentAt        DateTime @default(now())
  status        String   @default("sent")

  venue Venue @relation(fields: [venueId], references: [id])

  @@index([venueId, sentAt])
  @@index([venueId, tabId])
}

// What happened on a tab, as reported by the terminal. The id is generated by the terminal so a re-sent event is
// stored, and applied to the tab state and stock, only once.
model TabEvent {
  id               String   @id
  venueId          String
  deviceId         String
  // Null for stock_set, which is not about a tab
  tabId            String?
  customerName     String?
  // tab_opened | tab_renamed | tab_deleted | line_added | line_removed | settled | stock_set
  type             String
  lineId           String?
  productId        String?
  productName      String?
  unitPriceInCents Int?
  // Signed: positive for line_added, negative for line_removed
  quantityDelta    Int?
  // settled only
  amountInCents    Int?
  paymentMethod    String?
  commandId        String?
  items            Json?
  // stock_set: the counted stock, null to stop tracking
  stockSetTo       Int?
  // product_created / product_updated: the product's fields as sent by the terminal
  productData      Json?
  occurredAt       DateTime
  receivedAt       DateTime @default(now())

  venue  Venue  @relation(fields: [venueId], references: [id])
  device Device @relation(fields: [deviceId], references: [id])

  @@index([venueId, occurredAt])
  @@index([venueId, type, occurredAt])
}

// The venue's products and their stock. The dashboard manages the catalog and the terminals get it on every sync;
// the first terminal's own catalog was taken over once. The stock follows the terminals' line events and stock
// counts and the dashboard's StockAdjustments.
model Product {
  venueId           String
  // Generated by the server, or by the terminal that reported it before the dashboard managed the catalog
  productId         String
  name              String
  category          String?
  // The sell price: what the terminals charge
  priceInCents      Int
  // What the bar pays for one; null when not entered. Kept on the dashboard only, the terminals never get it
  buyPriceInCents   Int?
  // Null when stock is not tracked for this product. Can be negative: a sale is never blocked.
  stock             Int?
  // When the stock was last counted; line events that happened before it are already in the count
  countedAt         DateTime?
  // Warn when the stock drops to this level
  lowStockThreshold Int?
  // How many the bar wants in stock; the dashboard shows what to order to get there. Not sent to the terminals
  desiredStock      Int?
  // When it was created or last changed
  reportedAt        DateTime
  // Deleted on the dashboard: hidden on the terminals, kept because tabs and history refer to it
  archivedAt        DateTime?
  imageId           String?
  // When each field was last changed ({ name: ISO date, ... }): a change from the dashboard or an (offline)
  // terminal only wins over a later one per field, so edits of different fields never overwrite each other
  fieldUpdatedAt    Json?

  image ProductImage? @relation(fields: [imageId], references: [id])

  venue Venue @relation(fields: [venueId], references: [id])

  @@id([venueId, productId])
}

// A stock change made on the dashboard. The server applies it right away. Older ones may still have been applied
// by a terminal, which reported the outcome.
model StockAdjustment {
  id            String    @id @default(uuid())
  venueId       String
  productId     String
  productName   String
  // add (signed: a delivery, or breakage when negative) | set (a stock count)
  type          String
  quantity      Int
  note          String?
  requestedBy   String
  requestedById String
  // pending | applied | rejected | cancelled
  status        String    @default("pending")
  // The stock right after applying it
  stockAfter    Int?
  result        String?
  createdAt     DateTime  @default(now())
  processedAt   DateTime?

  venue Venue @relation(fields: [venueId], references: [id])

  @@index([venueId, status, createdAt])
  @@index([venueId, productId, createdAt])
}

// An open tab of the venue: the source of truth the terminals replace their own tabs with on every sync. Tabs are
// never closed, only emptied by a settlement; tab_deleted removes one.
model Tab {
  venueId      String
  // Generated by the terminal that opened it
  id           String
  customerName String
  openedAt     DateTime
  // Bumped by every change, so the dashboard can refuse to settle a tab that changed since it was shown
  version      Int      @default(0)
  // [{ id, productId, productName, unitPriceInCents, units: [{ id, addedAt, removedAt }] }]
  lines        Json
  updatedAt    DateTime @updatedAt

  venue Venue @relation(fields: [venueId], references: [id])

  @@id([venueId, id])
}

// A settlement made on a terminal (id = the settled event's id) or on the dashboard. Terminals read them as a feed
// after their cursor, which is the sequence number.
model Settlement {
  id            String   @id
  sequence      Int      @unique @default(autoincrement())
  venueId       String
  tabId         String
  customerName  String
  settledAt     DateTime
  // cash | payconiq | payment_pending | other
  paymentMethod String
  amountInCents Int
  // The settled lines, in the shape of Tab.lines with each line's settled and removed units
  lines         Json
  // Who settled it: a terminal, or a dashboard user
  deviceId      String?
  requestedBy   String?
  commandId     String?
  createdAt     DateTime @default(now())

  venue  Venue   @relation(fields: [venueId], references: [id])
  device Device? @relation(fields: [deviceId], references: [id])

  @@index([venueId, sequence])
  @@index([venueId, settledAt])
}

// A product picture, resized and cropped on upload. The id is the SHA-256 of the stored bytes, so the picture at
// an address never changes and can be cached forever, and the same picture is stored once.
model ProductImage {
  id          String   @id
  contentType String
  width       Int
  height      Int
  bytes       Bytes
  createdAt   DateTime @default(now())

  products Product[]
}