package main

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

	"github.com/joho/godotenv"

	"github.com/go-git/go-git/v5"
	"github.com/go-git/go-git/v5/plumbing/transport/ssh"
)

type ForgejoRepository struct {
	ID       int    `json:"id"`
	Name     string `json:"name"`
	FullName string `json:"full_name"`
	HTMLURL  string `json:"html_url"`
	SSHURL   string `json:"ssh_url"`
	CloneURL string `json:"clone_url"`
}

const (
	API_URL         = "/api/v1"
	API_USER_REPOS  = "/user/repos"
	API_CREATE_REPO = "/user/repos"
	API_DELETE_REPO = "/repos/%s/%s"
)

func showHelp() {
	fmt.Println("fj - A Forgejo CLI")
	fmt.Println("\nUsage:")
	fmt.Println("  fj <command> [arguments]")
	fmt.Println("\nAvailable Commands:")
	fmt.Println("  list                List all accessible repositories")
	fmt.Println("  clone <repo> <dir>  Clone a repository to the specified directory")
	fmt.Println("  create <repo>       Create a new repository")
	fmt.Println("  delete <repo>       Delete an existing repository")
	fmt.Println("  help                Show this help message")
	fmt.Println("\nEnvironment Variables:")
	fmt.Println("  FJ_HOST          Forgejo instance URL")
	fmt.Println("  FJ_USERNAME      Username to use for repository operations")
	fmt.Println("  FJ_API_TOKEN     Forgejo API token")
	fmt.Println("  FJ_SSH_KEY_PATH  Path to SSH key for git operations")
	fmt.Println("  FJ_SSH_USER      Username to use for SSH git operations")
}

func buildApiUrl(host string, token string, api string) string {
	return host + API_URL + api + "?token=" + token + "&limit=1000"
}

func buildApiUrlUserRepos(host string, token string) string {
	return buildApiUrl(host, token, API_USER_REPOS)
}

func buildApiUrlCreateRepo(host string, token string) string {
	return buildApiUrl(host, token, API_CREATE_REPO)
}

func buildApiUrlDeleteRepo(host string, token string, username string, reponame string) string {
	return buildApiUrl(host, token, fmt.Sprintf(API_DELETE_REPO, username, reponame))
}

func findRepo(repos []ForgejoRepository, name string) *ForgejoRepository {
	for _, repo := range repos {
		if repo.Name == name {
			return &repo
		}
	}
	return nil
}

func getRepos(host string, token string) ([]ForgejoRepository, error) {
	repos_json, err := http.Get(buildApiUrlUserRepos(host, token))
	if err != nil {
		return nil, err
	}

	var repos []ForgejoRepository
	err = json.NewDecoder(repos_json.Body).Decode(&repos)
	if err != nil {
		return nil, err
	}

	return repos, nil
}

func listRepos(host string, token string) {
	repos, err := getRepos(host, token)
	if err != nil {
		log.Fatalln(err)
		return
	}

	for _, repo := range repos {
		log.Println(repo.Name + " " + repo.CloneURL)
	}
}

func cloneRepo(host string, token string, sshUser string, keyPath string, repoName string, directory string) {
	repos, err := getRepos(host, token)
	if err != nil {
		log.Fatalln(err)
		return
	}

	repo := findRepo(repos, repoName)
	if repo == nil {
		log.Fatalf("Repository '%s' not found\n", repoName)
		return
	}

	publicKeys, err := ssh.NewPublicKeysFromFile(sshUser, keyPath, "")
	if err != nil {
		log.Fatalf("Failed to load SSH key: %v\n", err)
		return
	}

	_, err = git.PlainClone(directory, false, &git.CloneOptions{
		URL:      repo.SSHURL,
		Progress: os.Stdout,
		Auth:     publicKeys,
	})

	if err != nil {
		log.Fatalf("Failed to clone repository: %v\n", err)
		return
	}

	fmt.Printf("Successfully cloned %s to %s\n", repoName, directory)
}

func createRepo(host string, token string, repoName string) error {
	// Confirm with user
	fmt.Printf("Are you sure you want to create repository '%s'? (y/N): ", repoName)
	var response string
	fmt.Scanln(&response)
	if strings.ToLower(response) != "y" {
		return fmt.Errorf("repository creation cancelled")
	}

	// Prepare request body
	reqBody := map[string]interface{}{
		"name":    repoName,
		"private": true,
	}
	jsonBody, err := json.Marshal(reqBody)
	if err != nil {
		return err
	}

	// Create POST request
	url := buildApiUrlCreateRepo(host, token)
	req, err := http.NewRequest("POST", url, bytes.NewBuffer(jsonBody))
	if err != nil {
		return err
	}
	req.Header.Set("Content-Type", "application/json")

	// Send request
	client := &http.Client{}
	resp, err := client.Do(req)
	if err != nil {
		return err
	}
	defer resp.Body.Close()

	if resp.StatusCode != http.StatusCreated {
		return fmt.Errorf("failed to create repository. Status: %s", resp.Status)
	}

	fmt.Printf("Repository '%s' created successfully\n", repoName)

	repos, err := getRepos(host, token)
	if err != nil {
		log.Fatalln(err)
		return err
	}

	repo := findRepo(repos, repoName)
	if repo == nil {
		log.Fatalf("Repository '%s' not found\n", repoName)
		return err
	}

	// print the repo ssh clone url
	fmt.Printf("SSH clone URL: %s\n", repo.SSHURL)

	return nil
}

func deleteRepo(host string, token string, username string, repoName string) error {
	// First confirmation
	fmt.Printf("Are you sure you want to delete repository '%s'? (y/N): ", repoName)
	var response string
	fmt.Scanln(&response)
	if strings.ToLower(response) != "y" {
		return fmt.Errorf("repository deletion cancelled")
	}

	// Second confirmation with warning
	color := "\033[31m" // Red color
	reset := "\033[0m"  // Reset color
	fmt.Printf("%sWARNING: This will permanently delete all data in '%s'. This action cannot be undone!\nType the repository name to confirm: %s", color, repoName, reset)
	var confirmation string
	fmt.Scanln(&confirmation)
	if confirmation != repoName {
		return fmt.Errorf("repository deletion cancelled - name mismatch")
	}

	// Create DELETE request
	url := buildApiUrlDeleteRepo(host, token, username, repoName)
	req, err := http.NewRequest("DELETE", url, nil)
	if err != nil {
		return err
	}

	// Send request
	client := &http.Client{}
	resp, err := client.Do(req)
	if err != nil {
		return err
	}
	defer resp.Body.Close()

	if resp.StatusCode != http.StatusNoContent {
		return fmt.Errorf("failed to delete repository. Status: %s", resp.Status)
	}

	fmt.Printf("Repository '%s' deleted successfully\n", repoName)
	return nil
}

func main() {
	// Get the environment variables for Forgejo URL and api token
	FJ_HOST := os.Getenv("FJ_HOST")
	FJ_USERNAME := os.Getenv("FJ_USERNAME")
	FJ_API_TOKEN := os.Getenv("FJ_API_TOKEN")
	FJ_SSH_KEY_PATH := os.Getenv("FJ_SSH_KEY_PATH")
	FJ_SSH_USER := os.Getenv("FJ_SSH_USER")

	if FJ_HOST == "" || FJ_USERNAME == "" || FJ_API_TOKEN == "" || FJ_SSH_KEY_PATH == "" || FJ_SSH_USER == "" {
		if err := godotenv.Load(); err != nil {
			log.Fatalln("Please configure the FJ_HOST, FJ_API_TOKEN, FJ_SSH_KEY_PATH and FJ_SSH_USER environment variables to use fj.")
			return
		}

		FJ_HOST = os.Getenv("FJ_HOST")
		FJ_USERNAME = os.Getenv("FJ_USERNAME")
		FJ_API_TOKEN = os.Getenv("FJ_API_TOKEN")
		FJ_SSH_KEY_PATH = os.Getenv("FJ_SSH_KEY_PATH")
		FJ_SSH_USER = os.Getenv("FJ_SSH_USER")
	}

	flag.Parse()
	command := ""
	if flag.NArg() > 0 {
		command = flag.Arg(0)
	}

	switch command {
	case "list":
		listRepos(FJ_HOST, FJ_API_TOKEN)
	case "clone":
		if flag.NArg() != 3 {
			log.Fatalln("Usage: fj clone <repository-name> <directory>")
			return
		}
		repoName := flag.Arg(1)
		directory := flag.Arg(2)
		cloneRepo(FJ_HOST, FJ_API_TOKEN, FJ_SSH_USER, FJ_SSH_KEY_PATH, repoName, directory)
	case "create":
		if flag.NArg() != 2 {
			log.Fatalln("Usage: fj create <repository-name>")
			return
		}
		repoName := flag.Arg(1)
		if err := createRepo(FJ_HOST, FJ_API_TOKEN, repoName); err != nil {
			log.Fatalln(err)
		}
	case "delete":
		if flag.NArg() != 2 {
			log.Fatalln("Usage: fj delete <repository-name>")
			return
		}
		repoName := flag.Arg(1)
		if FJ_USERNAME == "" {
			log.Fatalln("Please set FJ_USERNAME environment variable")
			return
		}
		if err := deleteRepo(FJ_HOST, FJ_API_TOKEN, FJ_USERNAME, repoName); err != nil {
			log.Fatalln(err)
		}
	case "help":
		showHelp()
	default:
		showHelp()
		os.Exit(1)
	}
}