CREATE TYPE "KnowledgeItemStatus" AS ENUM ('DRAFT', 'PUBLISHED', 'ARCHIVED');

CREATE TABLE "KnowledgeBoard" (
    "id" TEXT NOT NULL,
    "tenantId" TEXT NOT NULL,
    "name" TEXT NOT NULL,
    "description" TEXT,
    "slug" TEXT NOT NULL,
    "sortOrder" INTEGER NOT NULL DEFAULT 0,
    "createdAt" TIMESTAMP(3) NOT NULL DEFAULT CURRENT_TIMESTAMP,
    "updatedAt" TIMESTAMP(3) NOT NULL,
    CONSTRAINT "KnowledgeBoard_pkey" PRIMARY KEY ("id")
);

CREATE TABLE "KnowledgeItem" (
    "id" TEXT NOT NULL,
    "boardId" TEXT NOT NULL,
    "tenantId" TEXT NOT NULL,
    "question" TEXT NOT NULL,
    "answer" TEXT NOT NULL,
    "tags" TEXT[],
    "status" "KnowledgeItemStatus" NOT NULL DEFAULT 'DRAFT',
    "sortOrder" INTEGER NOT NULL DEFAULT 0,
    "createdBy" TEXT NOT NULL,
    "createdAt" TIMESTAMP(3) NOT NULL DEFAULT CURRENT_TIMESTAMP,
    "updatedAt" TIMESTAMP(3) NOT NULL,
    CONSTRAINT "KnowledgeItem_pkey" PRIMARY KEY ("id")
);

CREATE UNIQUE INDEX "KnowledgeBoard_tenantId_slug_key" ON "KnowledgeBoard"("tenantId", "slug");
CREATE INDEX "KnowledgeBoard_tenantId_idx" ON "KnowledgeBoard"("tenantId");
CREATE INDEX "KnowledgeItem_tenantId_status_idx" ON "KnowledgeItem"("tenantId", "status");
CREATE INDEX "KnowledgeItem_boardId_status_idx" ON "KnowledgeItem"("boardId", "status");

ALTER TABLE "KnowledgeBoard" ADD CONSTRAINT "KnowledgeBoard_tenantId_fkey" FOREIGN KEY ("tenantId") REFERENCES "Tenant"("id") ON DELETE RESTRICT ON UPDATE CASCADE;
ALTER TABLE "KnowledgeItem" ADD CONSTRAINT "KnowledgeItem_boardId_fkey" FOREIGN KEY ("boardId") REFERENCES "KnowledgeBoard"("id") ON DELETE CASCADE ON UPDATE CASCADE;
ALTER TABLE "KnowledgeItem" ADD CONSTRAINT "KnowledgeItem_tenantId_fkey" FOREIGN KEY ("tenantId") REFERENCES "Tenant"("id") ON DELETE RESTRICT ON UPDATE CASCADE;