package cache

import (
	"fmt"
	"time"

	"github.com/apex/log"
	"github.com/sparetimecoders/goamqp"

	"gitlab.com/unboundsoftware/schemas/domain"
	"gitlab.com/unboundsoftware/schemas/hash"
)

type Cache struct {
	organizations map[string]domain.Organization
	users         map[string][]string
	apiKeys       map[string]domain.APIKey
	services      map[string]map[string]map[string]struct{}
	subGraphs     map[string]string
	lastUpdate    map[string]string
	logger        log.Interface
}

func (c *Cache) OrganizationByAPIKey(apiKey string) *domain.Organization {
	key, exists := c.apiKeys[apiKey]
	if !exists {
		return nil
	}
	org, exists := c.organizations[key.OrganizationId]
	if !exists {
		return nil
	}
	return &org
}

func (c *Cache) OrganizationsByUser(sub string) []domain.Organization {
	orgIds := c.users[sub]
	orgs := make([]domain.Organization, len(orgIds))
	for i, id := range orgIds {
		orgs[i] = c.organizations[id]
	}
	return orgs
}

func (c *Cache) ApiKeyByKey(key string) *domain.APIKey {
	k, exists := c.apiKeys[hash.String(key)]
	if !exists {
		return nil
	}
	return &k
}

func (c *Cache) Services(orgId, ref, lastUpdate string) ([]string, string) {
	key := refKey(orgId, ref)
	var services []string
	if lastUpdate == "" || c.lastUpdate[key] > lastUpdate {
		for k := range c.services[orgId][ref] {
			services = append(services, k)
		}
	}
	return services, c.lastUpdate[key]
}

func (c *Cache) SubGraphId(orgId, ref, service string) string {
	return c.subGraphs[subGraphKey(orgId, ref, service)]
}

func (c *Cache) Update(msg any, _ goamqp.Headers) (any, error) {
	switch m := msg.(type) {
	case *domain.OrganizationAdded:
		o := domain.Organization{}
		m.UpdateOrganization(&o)
		c.organizations[m.ID.String()] = o
		c.addUser(m.Initiator, o)
	case *domain.APIKeyAdded:
		key := domain.APIKey{
			Name:           m.Name,
			OrganizationId: m.OrganizationId,
			Key:            m.Key,
			Refs:           m.Refs,
			Read:           m.Read,
			Publish:        m.Publish,
			CreatedBy:      m.Initiator,
			CreatedAt:      m.When(),
		}
		c.apiKeys[m.Key] = key
		org := c.organizations[m.OrganizationId]
		org.APIKeys = append(org.APIKeys, key)
		c.organizations[m.OrganizationId] = org
	case *domain.SubGraphUpdated:
		c.updateSubGraph(m.OrganizationId, m.Ref, m.ID.String(), m.Service, m.Time)
	case *domain.Organization:
		c.organizations[m.ID.String()] = *m
		c.addUser(m.CreatedBy, *m)
		for _, k := range m.APIKeys {
			c.apiKeys[k.Key] = k
		}
	case *domain.SubGraph:
		c.updateSubGraph(m.OrganizationId, m.Ref, m.ID.String(), m.Service, m.ChangedAt)
	default:
		c.logger.Warnf("unexpected message received: %+v", msg)
	}
	return nil, nil
}

func (c *Cache) updateSubGraph(orgId string, ref string, subGraphId string, service string, updated time.Time) {
	if _, exists := c.services[orgId]; !exists {
		c.services[orgId] = make(map[string]map[string]struct{})
	}
	if _, exists := c.services[orgId][ref]; !exists {
		c.services[orgId][ref] = make(map[string]struct{})
	}
	c.services[orgId][ref][subGraphId] = struct{}{}
	c.subGraphs[subGraphKey(orgId, ref, service)] = subGraphId
	c.lastUpdate[refKey(orgId, ref)] = updated.Format(time.RFC3339Nano)
}

func (c *Cache) addUser(sub string, organization domain.Organization) {
	user, exists := c.users[sub]
	if !exists {
		c.users[sub] = []string{organization.ID.String()}
	} else {
		c.users[sub] = append(user, organization.ID.String())
	}
}

func New(logger log.Interface) *Cache {
	return &Cache{
		organizations: make(map[string]domain.Organization),
		users:         make(map[string][]string),
		apiKeys:       make(map[string]domain.APIKey),
		services:      make(map[string]map[string]map[string]struct{}),
		subGraphs:     make(map[string]string),
		lastUpdate:    make(map[string]string),
		logger:        logger,
	}
}

func refKey(orgId string, ref string) string {
	return fmt.Sprintf("%s<->%s", orgId, ref)
}

func subGraphKey(orgId string, ref string, service string) string {
	return fmt.Sprintf("%s<->%s<->%s", orgId, ref, service)
}