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

datasource db {
  provider = "postgresql"
}

// ─────────────────────────────────────────────────────────────────────────────
// Enums
// ─────────────────────────────────────────────────────────────────────────────

enum UserRole {
  ADMIN
  USER
}

enum RequestState {
  PENDING
  CHANGES_REQUESTED
  APPROVED
  REJECTED
  EXPIRED
  CONSUMED
  CANCELLED
}

enum NotificationType {
  REQUEST_CREATED
  REQUEST_UPDATED
  REQUEST_APPROVED
  REQUEST_REJECTED
  CHANGES_REQUESTED
  REQUEST_CONSUMED
  REQUEST_CANCELLED
  REQUEST_EXPIRED
  AGENT_DISABLED
  ADMIN_ACTION
  SETTINGS_CHANGED
}

enum GlobalSettingType {
  registration_enabled
  requests_enabled
}

// ─────────────────────────────────────────────────────────────────────────────
// Models
// ─────────────────────────────────────────────────────────────────────────────

/// A global (admin-only) platform setting, keyed by type.
model GlobalSetting {
  type      GlobalSettingType @id
  value     String
  updatedAt DateTime          @updatedAt
}

/// A human account. The first registered user becomes ADMIN.
model User {
  id          Int      @id @default(autoincrement())
  /// Normalized (lowercased) username — enforces case-insensitive uniqueness.
  username    String   @unique
  /// Original-cased display handle shown in the UI.
  displayName String
  password    String
  role        UserRole @default(USER)

  // Optional TOTP two-factor auth
  totpSecret  String?
  totpEnabled Boolean @default(false)

  // Admin can disable a human account entirely
  disabled Boolean @default(false)

  // Auto-delete of old change requests (opt-in, min 7 days, default 30)
  autoDeleteEnabled Boolean @default(false)
  autoDeleteDays    Int     @default(30)

  createdAt DateTime @default(now())
  updatedAt DateTime @updatedAt

  sessions       Session[]
  agents         Agent[]
  changeRequests ChangeRequest[] @relation("Owner")
  decisions      ChangeRequest[] @relation("Approver")
  notifications  Notification[]
  auditLogs      AuditLog[]      @relation("AuditActor")
}

/// A browser session for a human account (cookie-based auth).
model Session {
  id        Int      @id @default(autoincrement())
  hash      String   @unique
  userId    Int
  user      User     @relation(fields: [userId], references: [id], onDelete: Cascade)
  createdAt DateTime @default(now())

  @@index([userId])
}

/// An AGENT account. Fully managed by a human owner. Holds exactly one API key.
model Agent {
  id          Int     @id @default(autoincrement())
  name        String
  description String?
  website     String?
  iconUrl     String?
  /// The single API key the agent authenticates with.
  apiKey      String  @unique
  disabled    Boolean @default(false)
  /// Max simultaneous pending requests (1..10, human-configurable, default 5).
  maxPendingRequests Int @default(5)

  ownerId Int
  owner   User @relation(fields: [ownerId], references: [id], onDelete: Cascade)

  createdAt DateTime @default(now())
  updatedAt DateTime @updatedAt

  changeRequests ChangeRequest[]

  @@index([ownerId])
}

/// A structured change request submitted by an agent for human approval.
model ChangeRequest {
  id       Int    @id @default(autoincrement())
  /// Public UUID (v4) exposed to agents as request_id.
  publicId String @unique @default(uuid())

  title       String
  description String?
  /// Normalized changes array (diffs normalized, canonical ordering).
  changes     Json
  /// Original changes exactly as submitted (audit trail).
  rawChanges  Json
  metadata    Json?
  /// SHA-256 hash over the canonical (title + description + normalized changes).
  contentHash String

  state RequestState @default(PENDING)

  expiresAt DateTime

  // Decision fields
  comment         String?
  decidedAt       DateTime?
  approverId      Int?
  approver        User?     @relation("Approver", fields: [approverId], references: [id], onDelete: SetNull)
  /// HMAC-SHA256 signature of the approval receipt (platform-signed decision).
  signature       String?
  receiptIssuedAt DateTime?

  consumedAt  DateTime?
  cancelledAt DateTime?

  // Update tracking for the CHANGES_REQUESTED → resubmit loop
  updateCount Int      @default(0)
  /// True after an agent resubmits following a CHANGES_REQUESTED decision.
  resubmitted Boolean  @default(false)
  lastAgentUpdateAt DateTime?

  agentId Int
  agent   Agent @relation(fields: [agentId], references: [id], onDelete: Cascade)

  // The human who owns/reviews this request (the agent's owner at creation time).
  userId Int
  user   User @relation("Owner", fields: [userId], references: [id], onDelete: Cascade)

  createdAt DateTime @default(now())
  updatedAt DateTime @updatedAt

  @@index([userId, state])
  @@index([agentId, state])
  @@index([createdAt])
}

/// An in-app notification for a human account.
model Notification {
  id      Int              @id @default(autoincrement())
  type    NotificationType
  title   String
  message String
  /// Optional link to a change request (publicId).
  requestPublicId String?
  read    Boolean          @default(false)

  userId Int
  user   User @relation(fields: [userId], references: [id], onDelete: Cascade)

  createdAt DateTime @default(now())

  @@index([userId, read])
  @@index([userId, createdAt])
}

/// An audit log entry. Records privileged/admin actions and payload views.
model AuditLog {
  id       Int    @id @default(autoincrement())
  action   String
  /// Human-readable detail / JSON string of context.
  detail   String?
  /// Optional target references.
  targetType String?
  targetId   String?

  actorId Int?
  actor   User? @relation("AuditActor", fields: [actorId], references: [id], onDelete: SetNull)

  createdAt DateTime @default(now())

  @@index([createdAt])
  @@index([actorId])
}