projax/web/server.go

package web

import (
	"context"
	"embed"
	"errors"
	"fmt"
	"html/template"
	"io/fs"
	"log/slog"
	"net/http"
	"sort"
	"strings"

	"github.com/m/projax/store"
)

//go:embed templates/*.tmpl
var templatesFS embed.FS

//go:embed static/*
var staticFS embed.FS

// Server bundles handlers, templates, and the store.
type Server struct {
	Store  *store.Store
	pages  map[string]*template.Template
	Logger *slog.Logger
	Auth   *AuthConfig // nil → no auth (local dev / tests)
}

// New builds a Server. Each page is parsed alongside the layout into its own
// Template so per-page `define "content"` blocks don't shadow each other. The
// login page is intentionally NOT wrapped in the regular layout (chrome would
// imply you're already inside the app).
func New(s *store.Store, logger *slog.Logger) (*Server, error) {
	if logger == nil {
		logger = slog.Default()
	}
	funcs := template.FuncMap{
		"deref": func(p *string) string {
			if p == nil {
				return ""
			}
			return *p
		},
	}
	pages := map[string]*template.Template{}
	for _, name := range []string{"tree", "detail", "new", "classify", "error"} {
		t, err := template.New(name).Funcs(funcs).ParseFS(templatesFS,
			"templates/layout.tmpl",
			"templates/"+name+".tmpl",
		)
		if err != nil {
			return nil, fmt.Errorf("parse %s: %w", name, err)
		}
		pages[name] = t
	}
	loginTmpl, err := template.New("login").Funcs(funcs).ParseFS(templatesFS, "templates/login.tmpl")
	if err != nil {
		return nil, fmt.Errorf("parse login: %w", err)
	}
	pages["login"] = loginTmpl
	return &Server{Store: s, pages: pages, Logger: logger}, nil
}

// Routes wires every URL to a handler and returns the mux.
func (s *Server) Routes() http.Handler {
	mux := http.NewServeMux()

	mux.HandleFunc("GET /", s.handleTree)
	mux.HandleFunc("GET /i/", s.handleDetail)
	mux.HandleFunc("POST /i/", s.handleDetailWrite)
	mux.HandleFunc("GET /new", s.handleNewForm)
	mux.HandleFunc("POST /new", s.handleNewSubmit)
	mux.HandleFunc("GET /admin/classify", s.handleClassify)
	mux.HandleFunc("GET /login", s.handleLoginForm)
	mux.HandleFunc("POST /login", s.handleLoginSubmit)
	mux.HandleFunc("POST /logout", s.handleLogout)
	mux.HandleFunc("GET /healthz", func(w http.ResponseWriter, r *http.Request) {
		if err := s.Store.Pool.Ping(r.Context()); err != nil {
			http.Error(w, err.Error(), http.StatusServiceUnavailable)
			return
		}
		fmt.Fprintln(w, "ok")
	})

	static, _ := fs.Sub(staticFS, "static")
	mux.Handle("GET /static/", http.StripPrefix("/static/", http.FileServer(http.FS(static))))

	var h http.Handler = mux
	if s.Auth != nil {
		h = authMiddleware(*s.Auth, s.Logger, h)
	}
	return logging(s.Logger, h)
}

// --- handlers ---

type treeNode struct {
	Item     *store.Item
	Children []*treeNode
}

func (s *Server) handleTree(w http.ResponseWriter, r *http.Request) {
	if r.URL.Path != "/" {
		http.NotFound(w, r)
		return
	}
	items, err := s.Store.ListAll(r.Context())
	if err != nil {
		s.fail(w, r, err)
		return
	}
	areas, orphans, projaxN, maiN := buildForest(items)
	s.render(w, "tree", map[string]any{
		"Title":       "tree",
		"Areas":       areas,
		"Orphans":     orphans,
		"ProjaxCount": projaxN,
		"MaiCount":    maiN,
	})
}

func (s *Server) handleDetail(w http.ResponseWriter, r *http.Request) {
	path := strings.TrimPrefix(r.URL.Path, "/i/")
	if path == "" {
		http.NotFound(w, r)
		return
	}
	it, err := s.Store.GetByPath(r.Context(), path)
	if err != nil {
		s.fail(w, r, err)
		return
	}
	parents, err := s.parentOptions(r.Context())
	if err != nil {
		s.fail(w, r, err)
		return
	}
	s.render(w, "detail", map[string]any{
		"Title":         it.Title,
		"Item":          it,
		"ParentOptions": parents,
		"StatusOptions": []string{"active", "done", "archived"},
	})
}

func (s *Server) handleDetailWrite(w http.ResponseWriter, r *http.Request) {
	path := strings.TrimPrefix(r.URL.Path, "/i/")
	if base, ok := strings.CutSuffix(path, "/promote"); ok {
		s.handlePromote(w, r, base)
		return
	}
	it, err := s.Store.GetByPath(r.Context(), path)
	if err != nil {
		s.fail(w, r, err)
		return
	}
	if !it.Editable() {
		http.Error(w, "read-only source — use /promote", http.StatusForbidden)
		return
	}
	if err := r.ParseForm(); err != nil {
		s.fail(w, r, err)
		return
	}
	var parentID *string
	if v := strings.TrimSpace(r.FormValue("parent_id")); v != "" {
		parentID = &v
	}
	in := store.UpdateInput{
		Title:     strings.TrimSpace(r.FormValue("title")),
		Slug:      strings.TrimSpace(r.FormValue("slug")),
		ParentID:  parentID,
		ContentMD: r.FormValue("content_md"),
		Status:    strings.TrimSpace(r.FormValue("status")),
		Pinned:    r.FormValue("pinned") == "1",
		Archived:  r.FormValue("archived") == "1",
	}
	updated, err := s.Store.Update(r.Context(), it.ID, in)
	if err != nil {
		s.fail(w, r, err)
		return
	}
	http.Redirect(w, r, "/i/"+updated.Path, http.StatusSeeOther)
}

func (s *Server) handlePromote(w http.ResponseWriter, r *http.Request, path string) {
	it, err := s.Store.GetByPath(r.Context(), path)
	if err != nil {
		s.fail(w, r, err)
		return
	}
	if it.Source != "mai.projects" || it.SourceRefID == nil {
		http.Error(w, "promote: not a mai.projects row", http.StatusBadRequest)
		return
	}
	if err := r.ParseForm(); err != nil {
		s.fail(w, r, err)
		return
	}
	parentID := strings.TrimSpace(r.FormValue("parent_id"))
	slug := strings.TrimSpace(r.FormValue("slug"))
	title := strings.TrimSpace(r.FormValue("title"))
	if parentID == "" || slug == "" || title == "" {
		http.Error(w, "promote: parent_id, slug, title required", http.StatusBadRequest)
		return
	}
	newItem, err := s.Store.Promote(r.Context(), *it.SourceRefID, parentID, slug, title)
	if err != nil {
		s.fail(w, r, err)
		return
	}
	// HTMX inline-promote on /admin/classify expects a fragment; full-page promote redirects.
	if r.Header.Get("HX-Request") == "true" {
		fmt.Fprintf(w, `<tr class="promoted"><td colspan="6">Promoted to <a href="/i/%s">%s</a></td></tr>`,
			template.HTMLEscapeString(newItem.Path), template.HTMLEscapeString(newItem.Path))
		return
	}
	http.Redirect(w, r, "/i/"+newItem.Path, http.StatusSeeOther)
}

func (s *Server) handleNewForm(w http.ResponseWriter, r *http.Request) {
	parentPath := r.URL.Query().Get("parent")
	var parent *store.Item
	if parentPath != "" {
		p, err := s.Store.GetByPath(r.Context(), parentPath)
		if err != nil {
			s.fail(w, r, err)
			return
		}
		if !p.Editable() {
			http.Error(w, "parent must be a projax-native item", http.StatusBadRequest)
			return
		}
		parent = p
	}
	s.render(w, "new", map[string]any{
		"Title":         "new",
		"Parent":        parent,
		"StatusOptions": []string{"active", "done", "archived"},
	})
}

func (s *Server) handleNewSubmit(w http.ResponseWriter, r *http.Request) {
	if err := r.ParseForm(); err != nil {
		s.fail(w, r, err)
		return
	}
	kind := strings.TrimSpace(r.FormValue("kind"))
	if kind == "" {
		kind = "project"
	}
	var parentID *string
	if v := strings.TrimSpace(r.FormValue("parent_id")); v != "" {
		parentID = &v
	}
	if kind == "project" && parentID == nil {
		http.Error(w, "project requires a parent", http.StatusBadRequest)
		return
	}
	in := store.CreateInput{
		Kind:      []string{kind},
		Title:     strings.TrimSpace(r.FormValue("title")),
		Slug:      strings.TrimSpace(r.FormValue("slug")),
		ParentID:  parentID,
		ContentMD: r.FormValue("content_md"),
		Status:    strings.TrimSpace(r.FormValue("status")),
	}
	it, err := s.Store.Create(r.Context(), in)
	if err != nil {
		s.fail(w, r, err)
		return
	}
	http.Redirect(w, r, "/i/"+it.Path, http.StatusSeeOther)
}

func (s *Server) handleClassify(w http.ResponseWriter, r *http.Request) {
	orphans, err := s.Store.MaiOrphans(r.Context())
	if err != nil {
		s.fail(w, r, err)
		return
	}
	parents, err := s.parentOptions(r.Context())
	if err != nil {
		s.fail(w, r, err)
		return
	}
	s.render(w, "classify", map[string]any{
		"Title":         "classify",
		"Orphans":       orphans,
		"ParentOptions": parents,
	})
}

// --- helpers ---

// ParentOption is a flat option for the parent <select>.
type ParentOption struct {
	ID   string
	Path string
}

func (s *Server) parentOptions(ctx context.Context) ([]ParentOption, error) {
	items, err := s.Store.ListAll(ctx)
	if err != nil {
		return nil, err
	}
	var out []ParentOption
	for _, it := range items {
		if it.Source != "projax" {
			continue
		}
		out = append(out, ParentOption{ID: it.ID, Path: it.Path})
	}
	sort.Slice(out, func(i, j int) bool { return out[i].Path < out[j].Path })
	return out, nil
}

func buildForest(items []*store.Item) (areas []*treeNode, orphans []*store.Item, projaxN, maiN int) {
	byID := make(map[string]*treeNode, len(items))
	for _, it := range items {
		if it.Source == "projax" {
			projaxN++
			byID[it.ID] = &treeNode{Item: it}
		} else {
			maiN++
			orphans = append(orphans, it)
		}
	}
	for _, n := range byID {
		if n.Item.ParentID == nil {
			areas = append(areas, n)
			continue
		}
		if parent, ok := byID[*n.Item.ParentID]; ok {
			parent.Children = append(parent.Children, n)
		}
	}
	sort.Slice(areas, func(i, j int) bool { return areas[i].Item.Slug < areas[j].Item.Slug })
	for _, n := range byID {
		sort.Slice(n.Children, func(i, j int) bool { return n.Children[i].Item.Slug < n.Children[j].Item.Slug })
	}
	return
}

func (s *Server) render(w http.ResponseWriter, name string, data map[string]any) {
	t, ok := s.pages[name]
	if !ok {
		http.Error(w, "unknown page: "+name, http.StatusInternalServerError)
		return
	}
	entry := "layout"
	if name == "login" {
		// Login page is intentionally standalone — no nav chrome.
		entry = "login"
	}
	w.Header().Set("Content-Type", "text/html; charset=utf-8")
	if err := t.ExecuteTemplate(w, entry, data); err != nil {
		s.Logger.Error("render", "page", name, "err", err)
	}
}

func (s *Server) fail(w http.ResponseWriter, r *http.Request, err error) {
	status := http.StatusInternalServerError
	if errors.Is(err, store.ErrNotFound) {
		status = http.StatusNotFound
	}
	w.WriteHeader(status)
	s.render(w, "error", map[string]any{
		"Title":   "error",
		"Message": err.Error(),
	})
	s.Logger.Error("handler", "path", r.URL.Path, "err", err)
}

// logging wraps the mux with a tiny access log.
func logging(logger *slog.Logger, next http.Handler) http.Handler {
	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		next.ServeHTTP(w, r)
		logger.Info("req", "method", r.Method, "path", r.URL.Path, "remote", r.RemoteAddr)
	})
}