package adminapi

import (
	"time"

	"github.com/iceBear67/simplepages/api"
	"github.com/iceBear67/simplepages/internal/store"
)

// projectOf renders a stored project for the wire.
func (s *Server) projectOf(p *store.Project) api.Project {
	out := api.Project{
		Name:           p.Name,
		DisplayName:    p.DisplayName,
		IndexFile:      p.IndexFile,
		NotFoundFile:   p.NotFoundFile,
		SPAFallback:    p.SPAFallback,
		CacheControl:   p.CacheControl,
		RetentionCount: p.RetentionCount,
		RetentionGrace: p.RetentionGraceS,
		MaxFiles:       p.MaxFiles,
		MaxFileBytes:   p.MaxFileBytes,
		MaxTotalBytes:  p.MaxTotalBytes,
		CreatedAt:      p.CreatedAt,
		UpdatedAt:      p.UpdatedAt,
	}
	if s.BaseURL != "" {
		out.URL = api.SiteURL(s.BaseURL, p.Name)
	}
	out.ActiveDeployment = s.activeOf(p)
	return out
}

// activeOf summarises what a project is serving right now.
//
// It reads the registry rather than the database so listing a hundred projects
// stays one query. The summary carries what is being served — id, size,
// timestamps — and not the row's metadata or error text; those come from
// fetching the deployment itself.
func (s *Server) activeOf(p *store.Project) *api.Deployment {
	if s.Sites == nil {
		return nil
	}
	sp, ok := s.Sites.Lookup(p.Name)
	if !ok {
		return nil
	}
	d := sp.Active()
	if d == nil {
		return nil
	}
	out := &api.Deployment{
		ID:         d.ID,
		Project:    p.Name,
		State:      api.StateReady, // only a ready deployment can be active
		Active:     true,
		FileCount:  d.FileCount,
		TotalBytes: d.TotalBytes,
		CreatedAt:  d.CreatedAt,
	}
	if !d.ActivatedAt.IsZero() {
		t := d.ActivatedAt
		out.ActivatedAt = &t
	}
	return out
}

// deploymentOf renders a stored deployment for the wire.
//
// The row id stays behind: the wire only ever names a deployment by its public
// id, so nothing a client holds can be walked to a neighbouring row.
func deploymentOf(p *store.Project, d *store.Deployment) api.Deployment {
	return api.Deployment{
		ID:          d.PublicID,
		Project:     p.Name,
		State:       string(d.State),
		Active:      d.Active,
		FileCount:   d.FileCount,
		TotalBytes:  d.TotalBytes,
		Meta:        d.Meta,
		Error:       d.Error,
		CreatedAt:   d.CreatedAt,
		FinalizedAt: copyTime(d.FinalizedAt),
		ActivatedAt: copyTime(d.ActivatedAt),
	}
}

// keyOf renders a stored key. It deliberately has no access to the secret: the
// store never loads one in a form that could be rendered, only the hash.
func keyOf(k *store.APIKey, projectName string) api.Key {
	return api.Key{
		ID:        k.ID,
		Scope:     string(k.Scope),
		Project:   projectName,
		Name:      k.Name,
		CreatedAt: k.CreatedAt,
		ExpiresAt: copyTime(k.ExpiresAt),
		LastUsed:  copyTime(k.LastUsedAt),
		RevokedAt: copyTime(k.RevokedAt),
	}
}

// copyTime defensively copies an optional timestamp so a response value cannot
// alias a cached store row.
func copyTime(t *time.Time) *time.Time {
	if t == nil {
		return nil
	}
	v := *t
	return &v
}

// applyPatch folds a partial update into p, validating as it goes.
//
// A patch is all-or-nothing: it is applied to a copy by the caller, so a
// rejected field leaves the stored project untouched rather than half-updated.
func (s *Server) applyPatch(p *store.Project, patch *api.ProjectPatch) error {
	if patch == nil {
		return nil
	}
	if v := patch.DisplayName; v != nil {
		if err := checkText("display_name", *v, maxDisplayNameLen); err != nil {
			return err
		}
		p.DisplayName = *v
	}
	if v := patch.IndexFile; v != nil {
		if err := checkSitePath("index_file", *v); err != nil {
			return err
		}
		p.IndexFile = *v
	}
	if v := patch.NotFoundFile; v != nil {
		// The empty string is how a patch clears the custom 404 document; every
		// other value must name a real relative path.
		if *v != "" {
			if err := checkSitePath("not_found_file", *v); err != nil {
				return err
			}
		}
		p.NotFoundFile = *v
	}
	if v := patch.SPAFallback; v != nil {
		p.SPAFallback = *v
	}
	if v := patch.CacheControl; v != nil {
		if err := checkHeaderValue("cache_control", *v); err != nil {
			return err
		}
		p.CacheControl = *v
	}
	if v := patch.RetentionCount; v != nil {
		// At least one: retaining zero deployments would delete the active one.
		if *v < 1 || *v > 1000 {
			return api.Errorf(api.CodeBadRequest, "retention_count must be between 1 and 1000")
		}
		p.RetentionCount = *v
	}
	if v := patch.RetentionGrace; v != nil {
		if *v < 0 || *v > 30*24*3600 {
			return api.Errorf(api.CodeBadRequest,
				"retention_grace_s must be between 0 and %d", 30*24*3600)
		}
		p.RetentionGraceS = *v
	}
	if v := patch.MaxFiles; v != nil {
		if err := checkCeiling("max_files", int64(*v), int64(s.Limits.MaxManifestFiles)); err != nil {
			return err
		}
		p.MaxFiles = *v
	}
	if v := patch.MaxFileBytes; v != nil {
		if err := checkCeiling("max_file_bytes", *v, s.Limits.MaxFileBytes); err != nil {
			return err
		}
		p.MaxFileBytes = *v
	}
	if v := patch.MaxTotalBytes; v != nil {
		if *v < 1 {
			return api.Errorf(api.CodeBadRequest, "max_total_bytes must be positive")
		}
		p.MaxTotalBytes = *v
	}
	return nil
}

// checkCeiling enforces that a per-project limit is positive and does not
// exceed the server-wide one. A project may lower its own ceiling but never
// raise it past what the operator configured.
func checkCeiling(field string, v, ceiling int64) error {
	if v < 1 {
		return api.Errorf(api.CodeBadRequest, "%s must be positive", field)
	}
	if ceiling > 0 && v > ceiling {
		return api.Errorf(api.CodeBadRequest,
			"%s must be at most the server limit of %d", field, ceiling)
	}
	return nil
}