"""
   Flink 函数解析模块

   Copyright (c) Huawei Technologies Co., Ltd. 2026. All rights reserved.
   You can use this software according to the terms and conditions of the Mulan PSL v2.
   You may obtain a copy of Mulan PSL v2 at:
              http://license.coscl.org.cn/MulanPSL2
   THIS SOFTWARE IS PROVIDED ON AN "AS IS" BASIS, WITHOUT WARRANTIES OF ANY KIND,
   EITHER EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO NON-INFRINGEMENT,
   MERCHANTABILITY OR FIT FOR A PARTICULAR PURPOSE.
   See the Mulan PSL v2 for more details.

模块功能说明:
    本模块负责从 Flink 物理计划描述中解析函数调用信息，支持三种类型的函数识别:
    1. 函数调用形式: func_name(...) - 如 UPPER(col), CAST(... AS INT)
    2. 关键字形式: 关键字如 AND, OR, IS NULL, LIKE 等
    3. 操作符形式: 符号如 =, <>, >=, <=, *, + 等

    核心功能包括:
    - 加载和维护 Flink 函数字典 (flink_function_dictionary.json)
    - 构建正则表达式模式用于函数匹配
    - 解析算子描述中的函数调用
    - 判断函数是否支持以及参数类型是否兼容

设计理念:
    采用策略模式将函数匹配分为三个独立的正则模式，便于扩展和维护。
    通过类型归一化和函数支持映射，实现对函数兼容性的快速判断。
"""

from omnihelper.flink.function.dictionary_loader import FunctionDictionaryLoader
from omnihelper.flink.function.support_checker import FunctionSupportChecker
from omnihelper.flink.function.pattern_matcher import FunctionPatternMatcher


class FlinkFunctionParser:
    """
    Flink 函数解析器 - 核心类
    
    协调各子模块完成函数解析：
    1. 加载函数字典
    2. 构建匹配模式
    3. 检查函数支持性
    4. 匹配和分析函数
    """

    def __init__(self):
        """初始化函数解析器"""
        loader = FunctionDictionaryLoader()
        data = loader.load()

        self.function_list = data["function_list"]
        self.omni_functions = data["omni_functions"]
        self.func_support_map = data["func_support_map"]
        self.func_is_supported_types = data["func_is_supported_types"]
        self.cast_is_support_type = data["cast_is_support_type"]
        self.func_pattern = data["func_pattern"]
        self.keywords_pattern = data["keywords_pattern"]
        self.operator_pattern = data["operator_pattern"]

        support_checker = FunctionSupportChecker(
            self.func_support_map,
            self.func_is_supported_types,
            self.cast_is_support_type
        )

        self.pattern_matcher = FunctionPatternMatcher(
            self.func_pattern,
            self.keywords_pattern,
            self.operator_pattern,
            support_checker
        )

        self.support_checker = support_checker

    def check_cast_function(self, input_type):
        """校验 CAST 函数的源类型和目标类型是否支持"""
        return self.support_checker.check_cast_function(input_type)

    def is_func_type_supported(self, func_name, param_types):
        """判断函数在给定参数类型下是否支持"""
        return self.support_checker.is_func_type_supported(func_name, param_types)

    def parse_plan_description(self, description):
        """解析计划描述中的所有函数"""
        return self.pattern_matcher.parse_plan_description(description)

    def analyze_unsupported_functions(self, description, param_types_map=None):
        """分析描述中的不支持函数"""
        return self.pattern_matcher.analyze_unsupported_functions(description, param_types_map)