from py2neo import Graph, Node, Relationship

from Config import Config

# 1. 连接Neo4j数据库
graph = Graph(Config.NEO4J_URI, auth=Config.NEO4J_AUTH)

# 清空数据库
graph.delete_all()
print("数据库已清空")


# 2. 创建化学物质节点 (三种反应物+一种生成物)
reactant_A = Node("Chemical", name="铁", formula="Fe")
reactant_B = Node("Chemical", name="氧气", formula="O2")
reactant_C = Node("Chemical", name="水", formula="H2O")
product = Node("Chemical", name="氧化铁", formula="Fe2O3")

# 3. 创建反应节点并添加属性
reaction = Node("Reaction",
    name="铁锈蚀反应",
    equation="4Fe + 3O2 + 6H2O → 4Fe(OH)3",
    condition="常温常压"
)

# 4. 建立反应物与反应的关系（带计量系数属性）
rel_A = Relationship(reactant_A, "参与反应", reaction, coefficient=4)
rel_B = Relationship(reactant_B, "参与反应", reaction, coefficient=3)
rel_C = Relationship(reactant_C, "参与反应", reaction, coefficient=6)

# 5. 建立反应与生成物的关系
rel_product = Relationship(reaction, "生成", product, yield_rate="98%")

# 6. 将节点和关系提交到数据库
graph.create(reactant_A)
graph.create(reactant_B)
graph.create(reactant_C)
graph.create(product)
graph.create(reaction)
graph.create(rel_A)
graph.create(rel_B)
graph.create(rel_C)
graph.create(rel_product)

# 7. 查询示例：查找所有参与铁锈蚀反应的物质
query = """
MATCH (c:Chemical)-[r:PARTICIPATES_IN]->(re:Reaction {name:'铁锈蚀反应'})
RETURN c.name AS chemical, r.coefficient AS coefficient, re.equation AS equation
"""
result = graph.run(query)

for record in result:
    print(f"化学物质: {record['chemical']}, 计量系数: {record['coefficient']}")
    print(f"反应方程式: {record['equation']}")