// package main is the main package for the LapisDeploy program
package main

import (
	"encoding/json"
	"errors"
	"fmt"
	"log"
	"net/http"
	"os"
	"strings"

	"github.com/akamensky/argparse"
)

// Circle emoji
var Circles = map[string]string{
	"white":  "⚪️ ",
	"green":  "🟢 ",
	"yellow": "🟡 ",
	"red":    "🔴 ",
	"orange": "🟠 ",
}

// fileExists returns whether the given file or directory exists.
func fileExists(path string) (bool, error) {
	_, err := os.Stat(path)
	if err == nil {
		return true, nil
	}
	if os.IsNotExist(err) {
		return false, nil
	}
	return false, err
}

// Create a configuration struct
var configuration = Configuration{}

// handler is in charge of handling requests after the JSON has been parsed
func handler(data map[string]interface{}) {
	repository := data["repository"].(map[string]interface{})
	log.Default().Printf("Repo: %s", repository["full_name"])
	sendInfo(fmt.Sprintf("Handling webhook for `%s`...", repository["full_name"]))

	repo_name := repository["name"].(string)

	site, exists, err := getSite(repo_name)
	if err != nil {
		sendError(errors.New(fmt.Sprintf("Failed to check if site '%s' exists: %s", repo_name, err)))
		return
	}
	if exists {
		sendInfo("Updating repository...")
		if err := site.Update(); err != nil {
			sendError(err)
			return
		}
		new_site, exists, err := getSite(site.name)
		if err != nil || !exists {
			sendError(errors.New("Failed to update site data on a site we just updated: " + repo_name))
		}
		site = new_site
		sendInfo("Restarting server...")
		if error := site.Restart(); error != nil {
			sendError(error)
			return
		}
	} else {
		sendInfo("Cloning repositiory...")
		if error := CloneSite(repository["ssh_url"].(string), repo_name); error != nil {
			sendError(error)
			return
		}
		sendInfo("Starting server...")
		if site, exists, err = getSite(repo_name); err != nil {
			sendError(err)
			return
		}
		if error := site.Start(); error != nil {
			sendError(err)
			return
		}
		defer sendMessage(MatrixMessage{text: "🚀 Launched for the first time!"})
	}
	sendMessage(MatrixMessage{text: Circles["green"] + "Deployed successfully!"})
}

// main is the starting point of the program
func main() {
	// Parse arguments
	parser := argparse.NewParser("lapisdeploy", "Easily deploy Lapis web applications through Gitea webhooks")
	config_path := parser.String("c", "config", &argparse.Options{Required: false, Help: "Configuration file", Default: "./config.lua"})
	disable_matrix := parser.Flag("M", "disable-matrix", &argparse.Options{Required: false, Help: "Disable Matrix chat bot", Default: false})
	if err := parser.Parse(os.Args); err != nil { // Parse arguments
		fmt.Print(parser.Usage(err)) // Show usage if there's an error
		return
	}

	if exists, err := fileExists(*config_path); !exists {
		fmt.Printf("Invalid config file '%s'\n", *config_path)
		os.Exit(1)
	} else if err != nil {
		panic(err)
	}

	parseConfig(*config_path, &configuration) // Parse JSON configuration file
	// Disable Matrix if it's disabled in either the config or specified on CLI
	configuration.matrix.disabled = *disable_matrix || configuration.matrix.disabled

	http.HandleFunc("/", func(w http.ResponseWriter, r *http.Request) { // Webhook receiver
		log.Print("Recieved request!")
		var data map[string]interface{}
		err := json.NewDecoder(r.Body).Decode(&data)
		if err != nil {
			log.Panic(err)
			return
		}
		check_ips := []string{ // IPs of client to check against trusted_servers
			strings.Split(r.RemoteAddr, ":")[0],
			r.Header.Get("x-forwarded-for"),
		}
		found_trusted_server := false
		for _, server := range configuration.trusted_servers {
			if found_trusted_server {
				break
			}
			for _, ip := range check_ips {
				if ip == server {
					log.Printf("Request IP matches a trusted server (%s)", ip)
					go handler(data) // Run the handler
					fmt.Fprint(w, "Received!")
					found_trusted_server = true
					break
				}
			}
		}
		if !found_trusted_server {
			log.Print("Request IP doesn't match a trusted server! Dropping...")
		}
	})
	// Attempt to create sites_dir
	if exists, _ := fileExists(configuration.sites_dir); !exists {
		os.Mkdir(configuration.sites_dir, 640) // Permissions are 640 (Owner: rw, Group: r, All: none)
	}

	log.Printf("Starting Lapis Deploy on port %d...", configuration.port)

	startAllSites()                     // Start all the servers
	if !configuration.matrix.disabled { // Only start Matrix bot if --disable-matrix isn't passed
		go initMatrix() // Start Matrix stuff in a goroutine
	} else {
		log.Print("Matrix bot is disabled!")
	}
	log.Fatal(http.ListenAndServe(fmt.Sprintf(":%d", configuration.port), nil)) // Start HTTP server
}