package api

import (
	"bytes"
	"embed"
	"html/template"
	"net/http"

	"github.com/rs/zerolog"
)

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

// WebHandler serves HTML pages.
type WebHandler struct {
	templates *template.Template
	logger    zerolog.Logger
}

// NewWebHandler creates a new web handler.
func NewWebHandler(logger zerolog.Logger) (*WebHandler, error) {
	// Parse templates from embedded filesystem
	tmpl, err := template.ParseFS(templatesFS, "templates/*.html")
	if err != nil {
		return nil, err
	}

	return &WebHandler{
		templates: tmpl,
		logger:    logger,
	}, nil
}

// PageData holds data for page rendering.
type PageData struct {
	Title string
	Page  string
	Data  any
}

// render executes a page template within the base layout.
func (h *WebHandler) render(w http.ResponseWriter, page string, data PageData) {
	// First, render the page-specific content
	var contentBuf bytes.Buffer
	if err := h.templates.ExecuteTemplate(&contentBuf, page+".html", data); err != nil {
		h.logger.Error().Err(err).Str("page", page).Msg("failed to render page template")
		http.Error(w, "Internal Server Error", http.StatusInternalServerError)
		return
	}

	// Now render the base template with the content
	w.Header().Set("Content-Type", "text/html; charset=utf-8")
	if err := h.templates.ExecuteTemplate(w, "base.html", data); err != nil {
		h.logger.Error().Err(err).Msg("failed to render base template")
		http.Error(w, "Internal Server Error", http.StatusInternalServerError)
	}
}

// HandleIndex serves the main items page.
func (h *WebHandler) HandleIndex(w http.ResponseWriter, r *http.Request) {
	// Check if this is the root path
	if r.URL.Path != "/" {
		http.NotFound(w, r)
		return
	}

	data := PageData{
		Title: "Items",
		Page:  "items",
	}

	w.Header().Set("Content-Type", "text/html; charset=utf-8")
	if err := h.templates.ExecuteTemplate(w, "base.html", data); err != nil {
		h.logger.Error().Err(err).Msg("failed to render template")
		http.Error(w, "Internal Server Error", http.StatusInternalServerError)
	}
}

// HandleProjectsPage serves the projects page.
func (h *WebHandler) HandleProjectsPage(w http.ResponseWriter, r *http.Request) {
	data := PageData{
		Title: "Projects",
		Page:  "projects",
	}

	w.Header().Set("Content-Type", "text/html; charset=utf-8")
	if err := h.templates.ExecuteTemplate(w, "base.html", data); err != nil {
		h.logger.Error().Err(err).Msg("failed to render template")
		http.Error(w, "Internal Server Error", http.StatusInternalServerError)
	}
}

// HandleSchemasPage serves the schemas page.
func (h *WebHandler) HandleSchemasPage(w http.ResponseWriter, r *http.Request) {
	data := PageData{
		Title: "Schemas",
		Page:  "schemas",
	}

	w.Header().Set("Content-Type", "text/html; charset=utf-8")
	if err := h.templates.ExecuteTemplate(w, "base.html", data); err != nil {
		h.logger.Error().Err(err).Msg("failed to render template")
		http.Error(w, "Internal Server Error", http.StatusInternalServerError)
	}
}