package main

import (
	"html/template"
	"log"
	"net/http"
	"path"
	"strings"
)

var dialogTmpl = template.Must(template.New("dialogs").ParseFS(assets, "assets/page/dialogs.html"))

// isHX reports whether r was issued by htmx.
func isHX(r *http.Request) bool {
	return r.Header.Get("HX-Request") == "true"
}

// layoutTemplate names the template that renders a layout page for r: the
// whole document, or for boosted navigation and htmx history restores only
// the "partial" that hx.js swaps into the open page. The editor is never
// boosted.
func layoutTemplate(w http.ResponseWriter, r *http.Request, editMode bool) string {
	w.Header().Set("Vary", "HX-Boosted, HX-History-Restore-Request")
	if !editMode && (r.Header.Get("HX-Boosted") == "true" || r.Header.Get("HX-History-Restore-Request") == "true") {
		return "partial"
	}
	return "layout"
}

// redirectAfter sends the client to target once a mutation succeeded. htmx
// requests get HX-Redirect (assets/hx.js turns it into a history replace, so
// Back skips the pre-mutation page); plain form posts get a 303.
func redirectAfter(w http.ResponseWriter, r *http.Request, target string) {
	if isHX(r) {
		w.Header().Set("HX-Redirect", target)
		w.WriteHeader(http.StatusNoContent)
		return
	}
	http.Redirect(w, r, target, http.StatusSeeOther)
}

// pageURL returns the escaped, slash-terminated browser URL of the page at
// the wiki path p ("/" or "/a/b", trailing slash optional).
func pageURL(p string) string {
	p = strings.Trim(p, "/")
	if p == "" {
		return "/"
	}
	return fileURL(p) + "/"
}

// renderDialog writes the named dialog from dialogs.html.
func renderDialog(w http.ResponseWriter, name string, data any) {
	w.Header().Set("Content-Type", "text/html; charset=utf-8")
	if err := dialogTmpl.ExecuteTemplate(w, name, data); err != nil {
		log.Printf("dialog template error: %v", err)
	}
}

// serveDialog handles GET ?dialog=<name> for the page at urlPath.
func (h *handler) serveDialog(w http.ResponseWriter, r *http.Request, urlPath, fsPath string) {
	page := normalizeMovePath(urlPath)
	name := r.URL.Query().Get("dialog")
	if page == "/" && (name == "delete" || name == "move") {
		http.Error(w, "not available for the wiki root", http.StatusBadRequest)
		return
	}
	switch name {
	case "view":
		view, sortKey, order := readPageSettings(fsPath).viewSettings()
		renderDialog(w, "view", struct{ View, Sort, Order string }{view, sortKey, order})
	case "canvas":
		renderDialog(w, "canvas", nil)
	case "delete":
		renderDialog(w, "delete", struct{ Path string }{urlPath})
	case "move":
		// parent comes from the folder picker; default to the current one.
		parent := r.URL.Query().Get("parent")
		if parent == "" {
			parent = path.Dir(page)
		}
		renderDialog(w, "move", struct{ Parent, Name string }{parent, path.Base(page)})
	default:
		http.NotFound(w, r)
	}
}