package registry

import (
	"bytes"
	"encoding/gob"
	"fmt"

	"git.capotej.com/capotej/communique/config"
	"git.capotej.com/capotej/communique/models"
	"git.capotej.com/capotej/communique/views"
)

type Handler struct {
	handlerCfg config.Handler
}

// TODO rename to controller and controller.go
type Registry struct {
	cfg        config.Config
	persister  *models.Persister
	handlerMap map[string]Handler
}

func NewRegistry(cfg config.Config, persister *models.Persister) *Registry {
	reg := Registry{cfg: cfg, persister: persister}
	reg.handlerMap = make(map[string]Handler)
	for _, v := range cfg.Handlers {
		reg.handlerMap[fqn(v.Name, cfg.Domain)] = Handler{handlerCfg: v}
	}
	return &reg
}

func (r *Registry) Profile(name string) (map[string]interface{}, error) {
	handler := r.findByName(name)
	if handler == nil {
		return nil, nil
	}
	return views.RenderProfile(handler.handlerCfg.Name, r.cfg.Domain)
}

func (r *Registry) Outbox(name string) (map[string]interface{}, error) {
	handler := r.findByName(name)
	if handler == nil {
		return nil, nil
	}
	aso := models.NewOutboxItem(handler.handlerCfg)
	totalItems, err := r.persister.Count(aso)
	if err != nil {
		return nil, err
	}
	return views.RenderOutbox(handler.handlerCfg.Name, r.cfg.Domain, totalItems)
}

func (r *Registry) OutboxCollection(name string) (map[string]interface{}, error) {
	handler := r.findByName(name)
	if handler == nil {
		return nil, nil
	}
	aso := models.NewOutboxItem(handler.handlerCfg)
	page, err := r.persister.Collect(aso)
	if err != nil {
		return nil, err
	}
	var outboxItems []models.OutboxItem
	for _, v := range page {
		buf := bytes.NewBuffer(v)
		dec := gob.NewDecoder(buf)
		var outboxItem models.OutboxItem
		err = dec.Decode(&outboxItem)
		if err != nil {
			return nil, err
		}
		outboxItems = append(outboxItems, outboxItem)
	}
	return views.RenderOutboxCollection(handler.handlerCfg.Name, r.cfg.Domain, outboxItems)
}

func (r *Registry) Activity(name, id string) (map[string]interface{}, error) {
	handler := r.findByName(name)
	if handler == nil {
		return nil, nil
	}
	lookup := models.NewOutboxItem(handler.handlerCfg)
	lookup.Id = []byte(id)
	result, err := r.persister.Find(lookup)
	if err != nil {
		return nil, err
	}
	buf := bytes.NewBuffer(result)
	dec := gob.NewDecoder(buf)
	var outboxItem models.OutboxItem
	err = dec.Decode(&outboxItem)
	if err != nil {
		return nil, err
	}
	return views.RenderActivity(handler.handlerCfg.Name, r.cfg.Domain, outboxItem)
}

func (r *Registry) Note(name, id string) (map[string]interface{}, error) {
	handler := r.findByName(name)
	if handler == nil {
		return nil, nil
	}
	lookup := models.NewOutboxItem(handler.handlerCfg)
	lookup.Id = []byte(id)
	result, err := r.persister.Find(lookup)
	if err != nil {
		return nil, err
	}
	buf := bytes.NewBuffer(result)
	dec := gob.NewDecoder(buf)
	var outboxItem models.OutboxItem
	err = dec.Decode(&outboxItem)
	if err != nil {
		return nil, err
	}
	return views.RenderNote(handler.handlerCfg.Name, r.cfg.Domain, outboxItem)
}

func (r *Registry) WebfingerResource(fqn string) (*views.WebfingerResource, error) {
	handler := r.findByFQN(fqn)
	if handler == nil {
		handler = r.findByFQN("acct:" + fqn)
	}
	if handler == nil {
		return nil, nil
	}
	return views.RenderWebfingerResource(handler.handlerCfg.Name, r.cfg.Domain)
}

func fqn(name, domain string) string {
	return fmt.Sprintf("acct:%s@%s", name, domain)
}

func (r *Registry) findByFQN(fqn string) *Handler {
	handler, ok := r.handlerMap[fqn]
	if !ok {
		return nil
	}
	return &handler
}

func (r *Registry) findByName(name string) *Handler {
	return r.findByFQN(fqn(name, r.cfg.Domain))
}