syntax = "proto2";

// ifdef PROTOBUF_LITE: option optimize_for = LITE_RUNTIME;

package Polarx.ExecPlan;
option java_package = "com.mysql.cj.x.protobuf";

import "polarx.proto"; // comment_out_if PROTOBUF_LITE
import "polarx_expr.proto";
import "polarx_datatypes.proto";

//
// Reserved for session.
// Session id in header.
//

// Request.

message NewSession {
}

message CloseSession {
}

message EnumSession {
}

// Response.

message SessionInfo {
}

message SessionInfos {
    repeated SessionInfo sessions = 1;
}

//
// Basic components.
//

message TableInfo {
    optional int64 version = 1; // Multi-version?
    required Polarx.Datatypes.Scalar name = 2; // Need support string and place holder.
    optional Polarx.Datatypes.Scalar schema_name = 3; // Need support string and place holder.
}

message IndexInfo {
    required Polarx.Datatypes.Scalar name = 1; // Need support string and place holder.
    optional int32 use_parts = 2;
}

message Transaction {
}

message BloomFilter {
    required uint32 total_bits = 1;
    required uint32 number_hash = 2;
    required bytes strategy = 3; // 'murmur3_128'
    required bytes data = 4;
}

//Client send GetTSO message to Server
message GetTSO {
   required bytes leader_name = 1;
   required int32 batch_count = 2;
}

//Server return ResultTSO message to Client
message ResultTSO {
  required int32 error_no = 1;
  required uint64 ts = 2;
}

//
// Exec plan.
//

// 单个列条件
message KeyExpr {
    required Polarx.Datatypes.Scalar field = 1; // 需要能处理列名或列id，列id从0开始
    required Polarx.Datatypes.Scalar value = 2; // 需要能处理动态参数
}

// 完整的行条件，可包含多个列条件，and关系
message GetExpr {
    repeated KeyExpr keys = 1;
}

message GetPlan {
    required TableInfo table_info = 1;
    optional IndexInfo index_info = 2; // 如果没指定，默认走primary
    repeated GetExpr keys = 3; // 索引列过滤条件，如果为空就报错，全表扫描走TableScanPlan
}


message TableScanPlan {
    required TableInfo table_info = 1;
    optional IndexInfo index_info = 2; // 如果没指定，默认走primary
    optional bool reverse = 3; // 扫描顺序，默认正向
}

message KeyOnlyRangeScan {
    optional Transaction snapshot = 1;                   // 读取快照，只有作为 top plan 时填写
    optional TableInfo table_info = 3;                // 读取的目标 table
    optional IndexInfo index_info = 4;                // 读取的目标 index
    // optional Polarx.Expr.Expr key_expr = 5;           // scan 的条件
    // 这里写的应该是是索引列中的条件，类似
    // idx_field1 > 5 and idx_field2 > 1

    optional GetExpr key = 5;
    optional GetExpr end_key = 6;                // end 条件，可选
    optional bool reverse = 8;                        // 扫描顺序
    optional int64 flag = 9;                          // 预留
}

message RangeScan {
    optional Transaction snapshot = 1;                   // 读取快照，只有作为 top plan 时填写
    optional TableInfo table_info = 3;                // 读取的目标 table
    optional IndexInfo index_info = 4;                // 读取的目标 index
    // optional Polarx.Expr.Expr key_expr = 5;           // scan 的条件
    // 这里写的应该是是索引列中的条件，类似
    // idx_field1 > 5 and idx_field2 > 1

    optional GetExpr key = 5;
    optional GetExpr end_key = 6;                // end 条件，可选
    optional bool reverse = 8;                        // 扫描顺序
    optional int64 flag = 9;                          // 预留
}

message TableProject {
    required AnyPlan sub_read_plan = 1; // 只支持GET和SCAN两种就行
    repeated Polarx.Datatypes.Scalar fields = 2; // 支持列名和列id（int uint），从0开始
}

message Project {
    required AnyPlan sub_read_plan = 1;
    repeated Polarx.Datatypes.Scalar fields = 2; // 输出列名
    repeated Polarx.Expr.Expr exprs = 3; // 支持使用Expr全部功能，包括新增的ref，引用sub_read_plan的输出
}

message Filter {
    required AnyPlan sub_read_plan = 1;
    required Polarx.Expr.Expr expr = 2;
}

message Aggr {
    enum AggrType {
        COUNT_FUNC = 1;          // COUNT
        COUNT_DISTINCT_FUNC = 2; // COUNT(DISTINCT)
        SUM_FUNC = 3;            // SUM
        SUM_DISTINCT_FUNC = 4;  // SUM(DISTINCT)
        AVG_FUNC = 5;            // AVG
        AVG_DISTINCT_FUNC = 6;  // AVG(DISTINCT)
        MIN_FUNC = 7;            // MIN
        MAX_FUNC = 8;           // MAX
    };

    required AnyPlan sub_read_plan = 1;
    required AggrType type = 2;  //聚集函数类型
    required Polarx.Datatypes.Scalar field = 3;  //列名
    required Polarx.Expr.Expr expr = 4; //聚集函数对应的表达式 
}

message AnyPlan {
    enum PlanType {
        GET = 1;
        TABLE_SCAN = 2;
        TABLE_PROJECT = 3;
        PROJECT = 4;
        FILTER = 5;
        RANGE_SCAN = 8;
        //LIMIT = 7;
        AGGR = 9;
    };
    required PlanType plan_type = 1;
    optional GetPlan get_plan = 2;
    optional TableScanPlan table_scan_plan = 3;
    optional TableProject table_project = 4;
    optional Project project = 5;
    optional Filter filter = 6;
    optional RangeScan range_scan = 8;
    optional Aggr aggr = 9;

    // SortPlan sort_plan = 5;
    // ProjectPlan project_plan = 6;
    // FilterPlan filter_plan = 7;
    // LimitPlan limit_plan = 8;
    // AggPlan agg_plan = 9;
}

// server接收的plan
message ExecPlan {
  optional Transaction transaction = 1;
  optional AnyPlan plan = 2;
  optional bytes plan_digest = 3;
  repeated Polarx.Datatypes.Scalar parameters = 4; // 动态参数记录在这，从0开始 **有修改**

  repeated Polarx.Datatypes.SessionVariable session_variables = 5;
  optional int32 token = 6;
  optional bool reset_error = 7;
  optional bool compact_metadata = 8 [ default = false ];
  optional uint64 snapshot_seq = 9;
  optional uint64 commit_seq = 10;
  optional bool use_cts_transaction = 12;

  optional bool chunk_result = 11 [default = false];
  optional bool feed_back = 13 [default = false];
}