package api

import (
	"fmt"
	"html/template"
	"log"
	"net/http"
	"strings"
	"time"

	authpkg "jiggablend/internal/auth"
	"jiggablend/web"
)

type uiRenderer struct {
	templates *template.Template
}

type pageData struct {
	Title           string
	CurrentPath     string
	ContentTemplate string
	PageScript      string
	User            *authpkg.Session
	Error           string
	Notice          string
	Data            interface{}
}

func newUIRenderer() (*uiRenderer, error) {
	tpl, err := template.New("base").Funcs(template.FuncMap{
		"formatTime": func(t time.Time) string {
			if t.IsZero() {
				return "-"
			}
			return t.Local().Format("2006-01-02 15:04:05")
		},
		"statusClass": func(status string) string {
			switch status {
			case "completed":
				return "status-completed"
			case "running":
				return "status-running"
			case "failed":
				return "status-failed"
			case "cancelled":
				return "status-cancelled"
			case "online":
				return "status-online"
			case "offline":
				return "status-offline"
			case "busy":
				return "status-busy"
			default:
				return "status-pending"
			}
		},
		"progressInt": func(v float64) int {
			if v < 0 {
				return 0
			}
			if v > 100 {
				return 100
			}
			return int(v)
		},
		"derefInt": func(v *int) string {
			if v == nil {
				return ""
			}
			return fmt.Sprintf("%d", *v)
		},
		"derefString": func(v *string) string {
			if v == nil {
				return ""
			}
			return *v
		},
		"hasSuffixFold": func(value, suffix string) bool {
			return strings.HasSuffix(strings.ToLower(value), strings.ToLower(suffix))
		},
	}).ParseFS(
		web.GetTemplateFS(),
		"templates/*.html",
		"templates/partials/*.html",
	)
	if err != nil {
		return nil, fmt.Errorf("parse templates: %w", err)
	}
	return &uiRenderer{templates: tpl}, nil
}

func (r *uiRenderer) render(w http.ResponseWriter, data pageData) {
	w.Header().Set("Content-Type", "text/html; charset=utf-8")
	if err := r.templates.ExecuteTemplate(w, "base", data); err != nil {
		log.Printf("Template render error: %v", err)
		http.Error(w, "template render error", http.StatusInternalServerError)
		return
	}
}

func (r *uiRenderer) renderTemplate(w http.ResponseWriter, templateName string, data interface{}) {
	w.Header().Set("Content-Type", "text/html; charset=utf-8")
	if err := r.templates.ExecuteTemplate(w, templateName, data); err != nil {
		log.Printf("Template render error for %s: %v", templateName, err)
		http.Error(w, "template render error", http.StatusInternalServerError)
		return
	}
}