package routes

import (
	"database/sql"
	"net/http"
	"strings"
	"net/url"
)

type Router struct {
	DB *sql.DB
}

func NewRouter(db *sql.DB) *Router {
	return &Router{DB: db}
}

func (rt *Router) Register(mux *http.ServeMux) {
	mux.HandleFunc("/api/simulations", rt.handleSimulationsBase)
	mux.HandleFunc("/api/simulations/", rt.handleSimulationsPath)
}

func (rt *Router) handleSimulationsBase(w http.ResponseWriter, r *http.Request) {
	if r.Method == "OPTIONS" {
		rt.OptionsHandler(w, r)
		return
	}
	if r.Method == "GET" {
		rt.GetSimulations(w, r)
	} else {
		http.Error(w, "Method not allowed", http.StatusMethodNotAllowed)
	}
}

func (rt *Router) handleSimulationsPath(w http.ResponseWriter, r *http.Request) {
	if r.Method == "OPTIONS" {
		rt.OptionsHandler(w, r)
		return
	}

	pathParts := strings.Split(strings.Trim(r.URL.Path[len("/api/simulations/"):], "/"), "/")
	if len(pathParts) == 0 || pathParts[0] == "" {
		http.Error(w, "Not found", http.StatusNotFound)
		return
	}

	if pathParts[0] == "create" && r.Method == "POST" {
		rt.CreateSimulation(w, r)
		return
	}

	idStr := pathParts[0]

	if len(pathParts) == 1 {
		if r.Method == "GET" {
			rt.GetSimulationDetails(w, r, idStr)
		} else if r.Method == "DELETE" {
			rt.DeleteSimulation(w, r, idStr)
		} else {
			http.Error(w, "Method not allowed", http.StatusMethodNotAllowed)
		}
		return
	}

	if len(pathParts) > 1 {
		action := pathParts[1]
		if r.Method == "PUT" && action == "time" {
			rt.UpdateSimulationTime(w, r, idStr)
			return
		}
		if r.Method == "PUT" && action == "rename" {
			rt.RenameSimulation(w, r, idStr)
			return
		}
		if r.Method == "POST" && action == "upload" {
			rt.UploadSimulationResource(w, r, idStr)
			return
		}
		if r.Method == "DELETE" && action == "resources" && len(pathParts) > 2 {
			fileName, _ := url.PathUnescape(pathParts[2])
			rt.DeleteSimulationResource(w, r, idStr, fileName)
			return
		}
	}

	http.Error(w, "Not found", http.StatusNotFound)
}

func (rt *Router) OptionsHandler(w http.ResponseWriter, r *http.Request) {
	w.Header().Set("Access-Control-Allow-Origin", "*")
	w.Header().Set("Access-Control-Allow-Methods", "GET, PUT, POST, DELETE, OPTIONS")
	w.WriteHeader(http.StatusOK)
}