package main

import (
	"github.com/microsoft/go-mssqldb/azuread"
//    _ "github.com/microsoft/go-mssqldb"
    "database/sql"
    "context"
    "log"
    "fmt"
)

var db *sql.DB

func main() {
    var err error

    // Create connection pool
    db, err = sql.Open(azuread.DriverName, "sqlserver://xxx.database.windows.net:1433?database=xxx&fedauth=ActiveDirectoryManagedIdentity&user id=client_id_of_user-assigned_managed_identity")
    if err != nil {
        log.Fatal("Error creating connection pool: ", err.Error())
    }
    ctx := context.Background()
    err = db.PingContext(ctx)
    if err != nil {
        log.Fatal(err.Error())
    }
    fmt.Printf("Connected!\n")

    // Read table
    count, err := ReadTable()
    if err != nil {
        log.Fatal("Error reading Table: ", err.Error())
    }
    fmt.Printf("Read %d row(s) successfully.\n", count)

	// Call Hello function
	hello()
}

// ReadTable reads a record from a specific table
func ReadTable() (int, error) {
    ctx := context.Background()

    // Check if database is alive.
    err := db.PingContext(ctx)
    if err != nil {
        return -1, err
    }

    tsql := fmt.Sprintf("SELECT count(*) AS PlayerCount FROM Players;")

    // Execute query
    rows, err := db.QueryContext(ctx, tsql)
    if err != nil {
        return -1, err
    }

    defer rows.Close()

    var count int


    // Iterate through the result set.
    for rows.Next() {
        var PlayerCount int

        // Get values from row.
        err := rows.Scan(&PlayerCount)
        if err != nil {
            return -1, err
        }

        fmt.Printf("Player Count: %d\n", PlayerCount)
        count++
    }


    return count, nil
}


func hello() {
	fmt.Println("Hello World!")
}