/*
 This is a part of Tocy's Sample Code
 demo to use JsonCpp 
 https://github.com/open-source-parsers/jsoncpp
*/

#include <iostream>
#include <string>
#include <fstream>
#include <cassert>
#include "json/json.h"

using namespace std;

// =========================== parse-json ==================================
void demo_simple()
{
 ifstream ifs;
 ifs.open("checkjson.json");
 /*
 In this file, its content is : (key-value)
 {
 "name" : "tocy",
 "age" : 1000
 }
 */
 assert(ifs.is_open());
 
 Json::Reader reader;
 Json::Value root;
 if (!reader.parse(ifs, root, false))
 {
 cerr << "parse failed \n";
 return;
 }
 
 string name = root["name"].asString();
 int age = root["age"].asInt();
 
 cout << "demo read from filet result =============\n";
 cout << "name : " << name << endl;
 cout << "age : " << age << endl;
 cout << endl;
 
 ifs.close();
}

void demo_parse_mem_object()
{
 const char json_data[] = 
 "{\"name\" : \"Tocy\", \"salary\" : 100, \"msg\" : \"work hard\", \
\"files\" : [\"1.ts\", \"2.txt\"]}"; 

 Json::Reader reader;
 Json::Value root;
 // reader将Json字符串解析到root,root将包含Json里所有子元素 
 if (!reader.parse(json_data, json_data + sizeof(json_data), root))
 {
 cerr << "json parse failed\n";
 return;
 }
 
 cout << "demo read from memory using object ---------\n";
 string name = root["name"].asString();
 int salary = root["salary"].asInt();
 string msg = root["msg"].asString();
 cout << "name: " << name << " salary: " << salary;
 cout << " msg: " << msg << endl;
 cout << "enter files: \n";
 Json::Value files = root["files"]; // read array here
 for (unsigned int i = 0; i < files.size(); ++i)
 {
 cout << files[i].asString() << " ";
 }
 cout << endl << endl;
}

void demo_parse_mem_array()
{
 const char json_data[] = 
 "[{\"name\" : \"Tocy\", \"salary\" : 100}, {\"name\" : \"Kit\", \"salary\" : 89}, \
\"a json note\"]"; 

 Json::Reader reader;
 Json::Value root;
 // reader将Json字符串解析到root,root将包含Json里所有子元素 
 if (!reader.parse(json_data, json_data + sizeof(json_data), root))
 {
 cerr << "json parse failed\n";
 return;
 }
 
 cout << "demo read from memory using array---------\n";
 unsigned int count = root.size() - 1;
 for (unsigned int i = 0; i < count; ++i)
 {
 string name = root[i]["name"].asString();
 int salary = root[i]["salary"].asInt();
 cout << "name: " << name << " salary: " << salary << endl;
 }
 cout << "last msg: " << root[count].asString() << endl;
 cout << endl << endl;
}


// =================== save-json =====================================
void demo_write_simple()
{
 Json::Value root;
 Json::FastWriter writer;
 Json::Value person;
 
 person["name"] = "tocy";
 person["age"] = 1000;
 root.append(person);
 
 string json_file = writer.write(root);
 cout << "demo write json ==============\n";
 cout << json_file << endl;
}

void demo_write_object()
{
 Json::Value root;
 Json::FastWriter writer;
 
 root["name"] = "tocy";
 root["salary"] = 100;
 root["msg"] = "work hard";
 Json::Value files;
 files[0] = "1.ts";
 files[1] = "2.txt";
 root["files"] = files;
 
 string json_file = writer.write(root);
 cout << "demo write json object ==============\n";
 cout << json_file << endl;
}

void demo_write_array()
{
 Json::Value root;
 Json::FastWriter writer;

 {
 Json::Value person; 
 person["name"] = "Tocy";
 person["salary"] = 100;
 root[0] = person;
 }
 
 {
 Json::Value person; 
 person["name"] = "Kit";
 person["salary"] = 89;
 root[1] = person;
 }
 
 root[2] = "a json note"; 
 
 string json_file = writer.write(root);
 cout << "demo write json ==============\n";
 cout << json_file << endl;
}

int main(int argc, char * argv[])
{
 demo_simple();
 demo_parse_mem_object();
 demo_parse_mem_array();
 
 cout << "\n\nnext are write json example\n================================\n";

 demo_write_simple();
 demo_write_object();
 demo_write_array();
 return 0;
}