//
//  Copyright 2026 The InfiniFlow Authors. All Rights Reserved.
//
//  Licensed under the Apache License, Version 2.0 (the "License");
//  you may not use this file except in compliance with the License.
//  You may obtain a copy of the License at
//
//      http://www.apache.org/licenses/LICENSE-2.0
//
//  Unless required by applicable law or agreed to in writing, software
//  distributed under the License is distributed on an "AS IS" BASIS,
//  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
//  See the License for the specific language governing permissions and
//  limitations under the License.
//

package dao

import (
	"testing"

	"github.com/glebarez/sqlite"
	"gorm.io/gorm"

	"ragflow/internal/entity"
)

// setupKBTestDB initializes an in-memory SQLite database for KB DAO tests.
func setupKBTestDB(t *testing.T) *gorm.DB {
	t.Helper()

	db, err := gorm.Open(sqlite.Open(":memory:"), &gorm.Config{
		TranslateError: true,
	})
	if err != nil {
		t.Fatalf("failed to open sqlite: %v", err)
	}

	// Migrate knowledgebase table
	if err := db.AutoMigrate(&entity.Knowledgebase{}); err != nil {
		t.Fatalf("failed to migrate: %v", err)
	}

	return db
}

func testKnowledgebase(t *testing.T, db *gorm.DB, id string, docNum, tokenNum, chunkNum int64) *entity.Knowledgebase {
	t.Helper()
	kb := &entity.Knowledgebase{
		ID:       id,
		TenantID: "tenant-1",
		Name:     "test-kb-" + id,
		EmbdID:   "embd-1",
		DocNum:   docNum,
		TokenNum: tokenNum,
		ChunkNum: chunkNum,
		Status:   stringPtr(string(entity.StatusValid)),
	}
	if err := db.Create(kb).Error; err != nil {
		t.Fatalf("failed to create test kb: %v", err)
	}
	return kb
}

func stringPtr(s string) *string {
	return &s
}

func TestKnowledgebaseDAO_DecreaseDocumentNum(t *testing.T) {
	db := setupKBTestDB(t)
	pushDB(t, db)
	dao := NewKnowledgebaseDAO()

	testKnowledgebase(t, db, "kb-1", 5, 100, 50)

	err := dao.DecreaseDocumentNum("kb-1", 1, 20, 10)
	if err != nil {
		t.Fatalf("DecreaseDocumentNum failed: %v", err)
	}

	kb, err := dao.GetByID("kb-1")
	if err != nil {
		t.Fatalf("GetByID failed: %v", err)
	}
	if kb.DocNum != 4 {
		t.Fatalf("doc_num: expected 4, got %d", kb.DocNum)
	}
	if kb.TokenNum != 90 {
		t.Fatalf("token_num: expected 90, got %d", kb.TokenNum)
	}
	if kb.ChunkNum != 30 {
		t.Fatalf("chunk_num: expected 30, got %d", kb.ChunkNum)
	}
}

func TestKnowledgebaseDAO_DecreaseDocumentNum_ZeroDecrement(t *testing.T) {
	db := setupKBTestDB(t)
	pushDB(t, db)
	dao := NewKnowledgebaseDAO()

	testKnowledgebase(t, db, "kb-2", 3, 60, 15)

	err := dao.DecreaseDocumentNum("kb-2", 0, 0, 0)
	if err != nil {
		t.Fatalf("DecreaseDocumentNum failed: %v", err)
	}

	kb, err := dao.GetByID("kb-2")
	if err != nil {
		t.Fatalf("GetByID failed: %v", err)
	}
	if kb.DocNum != 3 {
		t.Fatalf("doc_num should be unchanged: expected 3, got %d", kb.DocNum)
	}
	if kb.TokenNum != 60 {
		t.Fatalf("token_num should be unchanged: expected 60, got %d", kb.TokenNum)
	}
	if kb.ChunkNum != 15 {
		t.Fatalf("chunk_num should be unchanged: expected 15, got %d", kb.ChunkNum)
	}
}