package sqimple

import (
	"context"
	"database/sql"
	"strings"
)

// https://www.sqlite.org/lang_delete.html
type DeleteStatement struct {
	Ctx context.Context
	DB  *sql.DB

	table SelectTable

	where []Where
	args  []any
}

func (s *DeleteStatement) Args() []any {
	return s.args
}

func (s *DeleteStatement) Exec() (sql.Result, error) {
	if s.DB != nil {
		if s.Ctx != nil {
			return s.DB.ExecContext(s.Ctx, s.String(), s.Args()...)
		}

		return s.DB.Exec(s.String(), s.Args()...)
	}

	return nil, ErrNoDatabase
}

func (s *DeleteStatement) IsValid() bool {
	if !s.table.IsValid() {
		return false
	}

	for _, w := range s.where {
		if !w.IsValid() {
			return false
		}
	}

	return false
}

func (s *DeleteStatement) String() string {
	strs := []string{"delete", s.table.String()}

	if len(s.where) > 0 {
		strs = append(strs, "where")

		for _, w := range s.where {
			strs = append(strs, w.String())
		}
	}

	return strings.Join(strs, " ")
}

func (s *DeleteStatement) Where(def string, args ...any) *DeleteStatement {
	s.where = append(s.where, Where(def))

	if len(args) > 0 {
		if s.args == nil {
			s.args = []any{}
		}

		s.args = append(s.args, args...)
	}

	return s
}

func Delete(from string) *DeleteStatement {
	s := &DeleteStatement{
		table: From(from),

		where: []Where{},
	}

	return s
}