package main

import (
	"context"
	"encoding/json"
	"fmt"

	"github.com/alexei/tinyforge/internal/staticsite"
	"github.com/alexei/tinyforge/internal/store"
	"github.com/alexei/tinyforge/internal/workload/plugin"
	"github.com/alexei/tinyforge/internal/workload/plugin/source/static"
)

// staticBackend is the bridge between the plugin static source and the
// existing staticsite.Manager. The Manager operates on store.StaticSite
// rows keyed by site ID; this adapter keeps a phantom static_sites row
// for every plugin-native static workload (row ID = workload ID) so the
// Manager's deploy pipeline runs unchanged.
//
// The phantom row carries no UI weight — the legacy /api/static_sites
// endpoints will still surface it during the cutover window, which is
// fine: it lets operators inspect state through the existing legacy UI
// until /apps grows the equivalent screens. When the legacy cutover
// finishes, we can rewrite the static source to operate against the
// containers table directly and drop this adapter.
type staticBackend struct {
	store *store.Store
	mgr   *staticsite.Manager
}

func newStaticBackend(st *store.Store, mgr *staticsite.Manager) *staticBackend {
	return &staticBackend{store: st, mgr: mgr}
}

func (b *staticBackend) Deploy(ctx context.Context, _ plugin.Deps, w plugin.Workload, _ plugin.DeploymentIntent) error {
	cfg, err := plugin.SourceConfigOf[static.Config](w)
	if err != nil {
		return fmt.Errorf("static backend: decode config: %w", err)
	}
	site, err := b.syncPhantomSite(w, cfg)
	if err != nil {
		return err
	}
	return b.mgr.Deploy(ctx, site.ID, true /* force */)
}

func (b *staticBackend) Teardown(ctx context.Context, _ plugin.Deps, w plugin.Workload) error {
	// Stop best-effort (the row may not exist yet if Deploy never ran).
	if _, err := b.store.GetStaticSiteByID(w.ID); err == nil {
		if err := b.mgr.Stop(ctx, w.ID); err != nil {
			// Log via the manager's own pipeline; we keep going so the
			// phantom row is always dropped.
			_ = err
		}
		_ = b.store.DeleteStaticSite(w.ID)
	}
	return nil
}

func (b *staticBackend) Reconcile(_ context.Context, _ plugin.Deps, w plugin.Workload) error {
	// The staticsite.HealthChecker already polls every site row; no
	// per-tick work is needed here. Reconcile becomes a no-op until the
	// inline port lands.
	_ = w
	return nil
}

// syncPhantomSite upserts a store.StaticSite keyed on the workload ID,
// translating the plugin Config into the legacy shape. It is also where
// we shape the "single public face" expectation of the legacy table into
// a single domain string.
func (b *staticBackend) syncPhantomSite(w plugin.Workload, cfg static.Config) (store.StaticSite, error) {
	domain := ""
	for _, f := range w.PublicFaces {
		// Pick the first enabled face. The API validator already caps
		// faces at one for v1, but iterate defensively.
		if f.Subdomain != "" || f.Domain != "" {
			d := f.Domain
			sub := f.Subdomain
			switch {
			case sub != "" && d != "":
				domain = sub + "." + d
			case sub == "" && d != "":
				domain = d
			case sub != "" && d == "":
				// Domain falls back to settings.domain inside the
				// Manager. Leave empty — Manager handles it.
				domain = sub
			}
			break
		}
	}

	site := store.StaticSite{
		ID:                      w.ID,
		Name:                    w.Name,
		Provider:                cfg.Provider,
		GiteaURL:                cfg.BaseURL,
		RepoOwner:               cfg.RepoOwner,
		RepoName:                cfg.RepoName,
		Branch:                  cfg.Branch,
		FolderPath:              cfg.FolderPath,
		AccessToken:             cfg.AccessToken,
		Domain:                  domain,
		Mode:                    cfg.Mode,
		RenderMarkdown:          cfg.RenderMarkdown,
		SyncTrigger:             "manual",
		StorageEnabled:          cfg.StorageEnabled,
		StorageLimitMB:          cfg.StorageLimitMB,
		NotificationURL:         w.NotificationURL,
		NotificationSecret:      w.NotificationSecret,
		WebhookSecret:           w.WebhookSecret,
		WebhookSigningSecret:    w.WebhookSigningSecret,
		WebhookRequireSignature: w.WebhookRequireSignature,
	}
	if err := b.store.UpsertStaticSiteWithID(site); err != nil {
		return store.StaticSite{}, fmt.Errorf("static backend: sync phantom site: %w", err)
	}
	return site, nil
}

// wireStaticBackend installs the adapter so the plugin static source
// becomes deployable. Called once from main() after the staticsite
// Manager is constructed. Safe to call multiple times only because
// static.SetBackend itself panics on the second call — keeping the
// invariant explicit.
func wireStaticBackend(st *store.Store, mgr *staticsite.Manager) {
	static.SetBackend(newStaticBackend(st, mgr))
}

// Unused but kept so the json import is referenced if we ever need to
// inspect raw SourceConfig blobs here for debugging.
var _ = json.Marshal