package app

import (
	"context"
	"sort"
	"sync"

	"forge.cadoles.com/arcad/edge/pkg/app"
	"forge.cadoles.com/arcad/edge/pkg/bundle"
	appModule "forge.cadoles.com/arcad/edge/pkg/module/app"
	"github.com/pkg/errors"
	"gitlab.com/wpetit/goweb/logger"
)

type ResolveAppURLFunc func(context.Context, *app.Manifest, string) (string, error)

type AppRepository struct {
	resolveAppURL ResolveAppURLFunc
	bundles       []string
	mutex         sync.RWMutex
}

// Get implements app.Repository
func (r *AppRepository) Get(ctx context.Context, id app.ID) (*app.Manifest, error) {
	r.mutex.RLock()
	defer r.mutex.RUnlock()

	manifest, err := r.findManifest(ctx, id)
	if err != nil {
		return nil, errors.WithStack(err)
	}

	return manifest, nil
}

// GetURL implements app.Repository
func (r *AppRepository) GetURL(ctx context.Context, id app.ID, from string) (string, error) {
	r.mutex.RLock()
	defer r.mutex.RUnlock()

	manifest, err := r.findManifest(ctx, id)
	if err != nil {
		return "", errors.WithStack(err)
	}

	url, err := r.resolveAppURL(ctx, manifest, from)
	if err != nil {
		return "", errors.WithStack(err)
	}

	return url, nil
}

// List implements app.Repository
func (r *AppRepository) List(ctx context.Context) ([]*app.Manifest, error) {
	r.mutex.RLock()
	defer r.mutex.RUnlock()

	manifests := make([]*app.Manifest, 0)

	for _, path := range r.bundles {
		bundleCtx := logger.With(ctx, logger.F("path", path))

		bundle, err := bundle.FromPath(path)
		if err != nil {
			logger.Error(bundleCtx, "could not load bundle", logger.E(errors.WithStack(err)))

			continue
		}

		manifest, err := app.LoadManifest(bundle)
		if err != nil {
			logger.Error(bundleCtx, "could not load manifest", logger.E(errors.WithStack(err)))

			continue
		}

		manifests = append(manifests, manifest)
	}

	sort.Sort(ByID(manifests))

	return manifests, nil
}

func (r *AppRepository) Update(resolveAppURL ResolveAppURLFunc, bundles []string) {
	r.mutex.Lock()
	defer r.mutex.Unlock()

	r.resolveAppURL = resolveAppURL
	r.bundles = bundles
}

func (r *AppRepository) findManifest(ctx context.Context, id app.ID) (*app.Manifest, error) {
	for _, path := range r.bundles {
		bundleCtx := logger.With(ctx, logger.F("path", path))

		bundle, err := bundle.FromPath(path)
		if err != nil {
			logger.Error(bundleCtx, "could not load bundle", logger.E(errors.WithStack(err)))

			continue
		}

		manifest, err := app.LoadManifest(bundle)
		if err != nil {
			logger.Error(bundleCtx, "could not load manifest", logger.E(errors.WithStack(err)))

			continue
		}

		if manifest.ID != id {
			continue
		}

		return manifest, nil
	}

	return nil, errors.WithStack(appModule.ErrNotFound)
}

func NewAppRepository() *AppRepository {
	return &AppRepository{
		resolveAppURL: func(ctx context.Context, m *app.Manifest, from string) (string, error) {
			return "", errors.New("unavailable")
		},
		bundles: []string{},
	}
}

var _ appModule.Repository = &AppRepository{}

type ByID []*app.Manifest

func (a ByID) Len() int           { return len(a) }
func (a ByID) Swap(i, j int)      { a[i], a[j] = a[j], a[i] }
func (a ByID) Less(i, j int) bool { return a[i].ID > a[j].ID }