// Package simpleorm provies a simple, basic ORM functionalities for making
// interaction with relational databses easier.
package simpleorm

import (
	"reflect"
	"strings"

	log "gitlab.com/gdulai/simpleloglvl"
)

// Type to access the ORM functionalities in a structured manner-
type ORM struct {
	cache *OrmCache
}

// Inits the ORM library.
// Param objs is an array which should be an array of the types which describe the tables.
func NewORM(objs ...any) *ORM {
	var parsers []*Parser
	var tables []*Table
	for _, obj := range objs {
		log.LogDebug("[ORM] Mapping type for: %s", reflect.TypeOf(obj).Name())
		parser := NewParser(obj)
		parsers = append(parsers, parser)
		tables = append(tables, parser.ParseColumns())
	}

	log.LogDebug("[ORM] Tables initiated, creating cache.")

	// Create cache with the initialized tables
	cache := NewOrmCache(tables)

	log.LogDebug("[ORM] Cache created.")

	// Finish the parsing with the constraints and add the to the tables
	for _, parser := range parsers {
		log.LogDebug("[ORM] Parsing constraing for: %s", parser.Table.Name)
		parser.ParseConstraints(cache)
		log.LogDebug("[ORM] Parsed constraints for: %s", parser.Table.Name)
	}

	return &ORM{cache: cache}
}

// Builds the DDL and returns it as a string
func (orm ORM) CreateDDL() string {
	var ddl strings.Builder

	tables := orm.cache.GetAll()

	for i, table := range tables {
		if i != 0 {
			ddl.WriteString("\n")
		}
		ddl.WriteString(table.ToDDL())
	}

	return ddl.String()
}