package exporter

import (
	"context"
	"fmt"
	"github.com/abelith/spellbook/internal/models"
	"io"
	"sync"
)

type Exporter interface {
	Export(ctx context.Context, ch <-chan models.Spell, w io.Writer) error
}

var (
	exporters = make(map[string]Exporter)
	mu        sync.Mutex
)

func Register(name string, exp Exporter) {
	mu.Lock()
	defer mu.Unlock()

	if exp == nil {
		panic("exporter: Exporter cannot be nil")
	}
	if _, ok := exporters[name]; ok {
		panic("exporter: Register called twice for " + name)
	}
	exporters[name] = exp
}

func Export(ctx context.Context, name string, ch <-chan models.Spell, w io.Writer) error {
	mu.Lock()
	exp, ok := exporters[name]
	mu.Unlock()

	if !ok {
		return fmt.Errorf("exporter %s not found", name)
	}

	return exp.Export(ctx, ch, w)
}