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

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

model Note {
  id            String    @id @default(cuid())
  title         String
  content       String
  type          String    @default("note")
  isFavorite    Boolean   @default(false)
  isPinned      Boolean   @default(false)
  createdAt     DateTime  @default(now())
  updatedAt     DateTime  @updatedAt
  creationSource String  @default("form") // 'form' | 'quick' | 'import'
  tags          NoteTag[]
  backlinks     Backlink[] @relation("BacklinkTarget")
  outbound      Backlink[] @relation("BacklinkSource")
  usageEvents   NoteUsage[]
  coUsageFrom  NoteCoUsage[] @relation("CoUsageFrom")
  coUsageTo    NoteCoUsage[] @relation("CoUsageTo")
}

model Tag {
  id    String    @id @default(cuid())
  name  String    @unique
  notes NoteTag[]
}

model NoteTag {
  noteId String
  tagId  String
  note   Note @relation(fields: [noteId], references: [id], onDelete: Cascade)
  tag    Tag  @relation(fields: [tagId], references: [id], onDelete: Cascade)

  @@id([noteId, tagId])
}

model Backlink {
  id           String   @id @default(cuid())
  sourceNoteId String
  targetNoteId String
  sourceNote   Note   @relation("BacklinkSource", fields: [sourceNoteId], references: [id], onDelete: Cascade)
  targetNote   Note   @relation("BacklinkTarget", fields: [targetNoteId], references: [id], onDelete: Cascade)
  createdAt    DateTime @default(now())

  @@unique([sourceNoteId, targetNoteId])
}

model NoteUsage {
  id        String   @id @default(cuid())
  noteId    String
  note      Note     @relation(fields: [noteId], references: [id], onDelete: Cascade)
  eventType String   // 'view' | 'search_click' | 'related_click' | 'link_click'
  query     String?
  metadata  String?
  createdAt DateTime @default(now())

  @@index([noteId, createdAt])
  @@index([eventType, createdAt])
}

model NoteCoUsage {
  id           String   @id @default(cuid())
  fromNoteId   String
  fromNote     Note     @relation("CoUsageFrom", fields: [fromNoteId], references: [id], onDelete: Cascade)
  toNoteId     String
  toNote       Note     @relation("CoUsageTo", fields: [toNoteId], references: [id], onDelete: Cascade)
  weight       Int      @default(1) // times viewed together
  createdAt    DateTime @default(now())
  updatedAt    DateTime @updatedAt

  @@unique([fromNoteId, toNoteId])
  @@index([fromNoteId])
  @@index([toNoteId])
}

model NoteVersion {
  id        String   @id @default(cuid())
  noteId    String
  title     String
  content   String
  createdAt DateTime @default(now())

  @@index([noteId, createdAt])
}