-- Notifications Engine (Sprint 2-3). NU o notificare per eveniment: motorul
-- decide daca merita, cui, ce severitate, daca se agrega si cand se livreaza.

DO $$ BEGIN
  CREATE TYPE "notification_severity" AS ENUM
    ('CRITICAL','ACTION_REQUIRED','WARNING','INFORMATION','INTELLIGENCE','SYSTEM');
EXCEPTION WHEN duplicate_object THEN NULL; END $$;

DO $$ BEGIN
  CREATE TYPE "notification_status" AS ENUM
    ('PENDING','SCHEDULED','DELIVERING','DELIVERED','READ','ACKNOWLEDGED',
     'DISMISSED','FAILED','EXPIRED','ESCALATED');
EXCEPTION WHEN duplicate_object THEN NULL; END $$;

CREATE TABLE IF NOT EXISTS "notifications" (
  "id" uuid PRIMARY KEY DEFAULT gen_random_uuid() NOT NULL,
  "tenant_id" uuid NOT NULL,
  "workspace_id" uuid,
  "recipient_user_id" uuid NOT NULL,
  "category" text NOT NULL,
  "severity" "notification_severity" NOT NULL,
  "title" text NOT NULL,
  "body" text,
  "source_event_id" uuid,
  "source_entity_type" text,
  "source_entity_id" text,
  "action_url" text,
  "action_type" text,
  "status" "notification_status" DEFAULT 'PENDING' NOT NULL,
  "deduplication_key" text NOT NULL,
  "aggregation_key" text,
  "aggregated_count" integer DEFAULT 1 NOT NULL,
  "channels" jsonb DEFAULT '["in_app"]'::jsonb NOT NULL,
  "scheduled_at" timestamp,
  "expires_at" timestamp,
  "created_at" timestamp DEFAULT now() NOT NULL,
  "updated_at" timestamp DEFAULT now() NOT NULL,
  "read_at" timestamp,
  "acknowledged_at" timestamp,
  "snoozed_until" timestamp,
  "metadata" jsonb DEFAULT '{}'::jsonb NOT NULL
);
CREATE INDEX IF NOT EXISTS "notifications_recipient_idx" ON "notifications" ("recipient_user_id","status");
CREATE INDEX IF NOT EXISTS "notifications_tenant_idx" ON "notifications" ("tenant_id","created_at");
CREATE INDEX IF NOT EXISTS "notifications_dedup_idx" ON "notifications" ("deduplication_key","created_at");

CREATE TABLE IF NOT EXISTS "notification_preferences" (
  "id" uuid PRIMARY KEY DEFAULT gen_random_uuid() NOT NULL,
  "tenant_id" uuid NOT NULL,
  "user_id" uuid NOT NULL,
  "category" text,
  "enabled" integer DEFAULT 1 NOT NULL,
  "minimum_severity" "notification_severity" DEFAULT 'INFORMATION' NOT NULL,
  "quiet_hours_start" integer,
  "quiet_hours_end" integer,
  "critical_bypasses_quiet_hours" integer DEFAULT 1 NOT NULL,
  "timezone" text DEFAULT 'Europe/Bucharest' NOT NULL,
  "created_at" timestamp DEFAULT now() NOT NULL,
  "updated_at" timestamp DEFAULT now() NOT NULL
);
-- NULLS NOT DISTINCT: category NULL inseamna "toate categoriile" si trebuie sa
-- fie unic per (user, tenant), altfel ON CONFLICT n-ar prinde randul implicit.
CREATE UNIQUE INDEX IF NOT EXISTS "notification_prefs_uq"
  ON "notification_preferences" ("user_id","tenant_id","category") NULLS NOT DISTINCT;

CREATE TABLE IF NOT EXISTS "notification_processed_events" (
  "id" uuid PRIMARY KEY DEFAULT gen_random_uuid() NOT NULL,
  "rule_id" text NOT NULL,
  "event_id" uuid NOT NULL,
  "processed_at" timestamp DEFAULT now() NOT NULL
);
CREATE UNIQUE INDEX IF NOT EXISTS "notification_processed_uq"
  ON "notification_processed_events" ("rule_id","event_id");