package db

import (
	"context"
	"database/sql"
	"database/sql/driver"
	"time"

	"contrib.go.opencensus.io/integrations/ocsql"
	"entgo.io/ent/dialect"
	entsql "entgo.io/ent/dialect/sql"
	pgx "github.com/jackc/pgx/v5/stdlib"
	"gitserver.in/patialtech/rano/config"
	"gitserver.in/patialtech/rano/db/ent"
	"gitserver.in/patialtech/rano/util/logger"
)

type connector struct {
	dsn string
}

// New *sql.DB instance
func New() *sql.DB {
	databaseUrl := config.Read().DbURL
	db := sql.OpenDB(connector{dsn: databaseUrl})
	db.SetMaxOpenConns(50)
	db.SetMaxIdleConns(5)
	db.SetConnMaxLifetime(0) // Maximum amount of time a connection can be reused (0 means no limit)
	return db
}

func (c connector) Connect(context.Context) (driver.Conn, error) {
	return c.Driver().Open(c.dsn)
}

func (connector) Driver() driver.Driver {
	return ocsql.Wrap(
		pgx.GetDefaultDriver(),
		ocsql.WithAllTraceOptions(),
		ocsql.WithRowsClose(false),
		ocsql.WithRowsNext(false),
		ocsql.WithDisableErrSkip(true),
	)
}

// Client for pgx
//
// https://entgo.io/docs/sql-integration
func Client() *ent.Client {
	// Create an ent.Driver from `db`.
	drv := entsql.OpenDB(dialect.Postgres, New())
	cl := ent.NewClient(ent.Driver(drv))
	cl.Use(AuditHook)
	return cl
}

// A AuditHook is an example for audit-log hook.
func AuditHook(next ent.Mutator) ent.Mutator {
	type Entity interface {
		GetID() (int64, error)
	}
	return ent.MutateFunc(func(ctx context.Context, m ent.Mutation) (v ent.Value, err error) {
		var id int64
		start := time.Now()
		defer func() {
			saveAudit(ctx, id, m.Type(), m.Op().String(), time.Since(start), err)
		}()

		v, err = next.Mutate(ctx, m)

		if en, ok := v.(Entity); ok {
			id, _ = en.GetID()
		}
		logger.Info("** %v", v)
		return
	})
}

func saveAudit(_ context.Context, entID int64, entT, op string, d time.Duration, err error) {
	logger.Info("audit: %d, %s, %s, %s, %v", entID, entT, op, d, err)
	// ml.SetCreatedAt(time.Now())
	// if usr := auth.CtxUser(ctx); usr != nil {
	// 	ml.SetByID(usr.ID)
	// 	ml.SetBy(usr.DisplayName)
	// }

	// switch op := m.Op(); {
	// case op.Is(ent.OpCreate):
	// 	ml.SetOperation("Create")

	// case op.Is(ent.OpUpdate):
	// 	ml.SetOperation("Update")
	// case op.Is(ent.OpUpdateOne):
	// 	ml.SetOperation("UpdateOne")

	// case op.Is(ent.OpDelete):
	// 	ml.SetOperation("Delete")
	// case op.Is(ent.OpDeleteOne):
	// 	ml.SetOperation("DeleteOne")
	// }
}