package main

import (
	"bytes"
	"encoding/json"
	"fmt"

	"io/ioutil"
	"log"
	"net/http"
	"os"
	"os/exec"
	"os/user"
	"path/filepath"
	"strings"

	"github.com/go-openapi/loads/fmts"
	"github.com/go-openapi/spec"
)

const (
	swaggerURL = "../docs/swagger.yml"
	rootTmpDir = "tmp"
)

var cwd string

func main() {
	os.RemoveAll(rootTmpDir)
	cwd, _ = os.Getwd()
	defer func() {
		os.RemoveAll(rootTmpDir)
	}()

	// Download swagger yaml and convert to JSON
	d, err := fmts.YAMLDoc(swaggerURL)
	if err != nil {
		log.Fatalf("Failed to convert swagger yaml to json: %v", err)
	}

	var sw spec.Swagger
	if err := json.Unmarshal(d, &sw); err != nil {
		log.Fatalf("Failed to convert swagger yaml to json: %v", err)
	}

	version := sw.Info.Version
	fmt.Printf("VERSION: %s\n", version)

	swg, err := ioutil.ReadFile(swaggerURL)
	if err != nil {
		log.Fatalf("Failed to load swagger file: %v", err)
	}
	gistURL := createGist(swg)

	var only string
	if len(os.Args) > 1 && os.Args[1] != "" {
		only = os.Args[1]
	}

	var languages []string
	if only != "" {
		languages = append(languages, only)
	} else {
		// Download available languages from swagger generator api
		languages = getLanguages()
	}

	for _, language := range languages {
		var skipFiles []string
		tmpDir := filepath.Join(rootTmpDir, language)
		srcDir := filepath.Join(tmpDir, "src")
		clientDir := filepath.Join(tmpDir, fmt.Sprintf("%s-client", language))
		short := language

		options := make(map[string]interface{})
		var deploy [][]string

		// Specfic language configurations
		switch language {
		case "go":
			options["packageName"] = "functions"
			options["packageVersion"] = version
		case "ruby":
			skipFiles = append(skipFiles, "#{gem_name}.gemspec")
			deploy = append(deploy, []string{"gem", "build #{gem_name}.gemspec", "gem push #{gem_name}-#{version}.gem"})
			options["gemName"] = "oracle_functions"
			options["moduleName"] = "OracleFunctions"
			options["gemVersion"] = version
			options["gemHomepage"] = "https://github.com/treeder/functions_ruby"
			options["gemSummary"] = "Ruby gem for Oracle Functions"
			options["gemDescription"] = "Ruby gem for Oracle Functions."
			options["gemAuthorEmail"] = "treeder@gmail.com"
		case "javascript":
			short = "js"
			options["projectName"] = "oracle_functions"
			deploy = append(deploy, []string{"npm", "publish"})
		default:
			continue
		}

		log.Printf("Generating `%s` client...\n", language)
		err = os.MkdirAll(clientDir, 0777)
		if err != nil {
			log.Printf("Failed to create temporary directory for %s client. Skipping...", language)
		}

		// Generate client
		if language == "go" {
			err := genSwaggerClient(clientDir)
			if err != nil {
				log.Printf("Failed to (swagger-go) generated %s client. Skipping...", language)
				continue
			}
		} else {
			gen, err := generateClient(gistURL, language, options)
			if err != nil {
				log.Printf("Failed to generated %s client. Skipping...", language)
				continue
			}

			// Download generated client
			log.Printf("Downloading `%s` client...\n", language)
			gf, err := getFile(strings.Replace(gen.Link, "https", "http", 1))
			if err != nil {
				log.Printf("Failed to download generated %s client. Skipping...", language)
			}
			ioutil.WriteFile(filepath.Join(tmpDir, "gen.zip"), gf, 0777)

			// Unzip
			log.Printf("Unzipping `%s` client...\n", language)
			exec.Command("unzip", "-o", filepath.Join(tmpDir, "gen.zip"), "-d", tmpDir).Run()
			os.Remove(filepath.Join(tmpDir, "gen.zip"))
		}

		branch := fmt.Sprintf("update-version-%s", version)

		log.Printf("Cloning previous `%s` source...\n", language)
		exec.Command("git", "clone", fmt.Sprintf("git@github.com:funcy/functions_%s.git", short), srcDir).Run()

		// Skip language specific files
		for _, skip := range skipFiles {
			os.Remove(filepath.Join(tmpDir, clientDir, skip))
		}

		// Copying new client
		log.Printf("Copying new `%s` client to src directory\n", language)

		// Only solution I found
		filepath.Walk(clientDir, func(path string, info os.FileInfo, err error) error {
			if path == clientDir {
				return nil
			}
			exec.Command("cp", "-r", path, srcDir).Run()
			if info.IsDir() {
				return filepath.SkipDir
			}
			return nil
		})

		f, err := os.OpenFile(filepath.Join(srcDir, "VERSION"), os.O_TRUNC|os.O_WRONLY, 0644)
		if err != nil {
			log.Printf("Failed to save new `%s` VERSION file. Skipping...", language)
			continue
		}
		f.WriteString(version)
		f.Close()

		os.Chdir(srcDir)
		exec.Command("git", "checkout", "-b", branch).Run()
		exec.Command("git", "add", ".").Run()
		exec.Command("git", "commit", "-am", fmt.Sprintf("Updated to API version %s", version)).Run()

		log.Printf("Pushing new `%s` client\n", language)
		r := exec.Command("git", "push", "origin", branch).Run()
		if r != nil && r.Error() != "" {
			log.Printf("Failed to push new version: %s\n", r.Error())
			break
		}

		log.Printf("Releasing new `%s` client\n", language)
		for _, d := range deploy {
			exec.Command(d[0], d[1])
		}

		log.Printf("Updated `%s` client to `%s` \n", language, version)

		os.Chdir(cwd)
	}
}

type generatedClient struct {
	Link string `json:"link"`
}

func generateClient(url, lang string, options map[string]interface{}) (gc generatedClient, err error) {
	payload := map[string]interface{}{
		"swaggerUrl": url,
		"options":    options,
	}

	data, err := json.Marshal(payload)
	if err != nil {
		return
	}

	resp, err := http.Post(fmt.Sprintf("http://generator.swagger.io/api/gen/clients/%s", lang), "application/json", bytes.NewBuffer(data))
	if err != nil {
		return
	}
	result, err := ioutil.ReadAll(resp.Body)
	if err != nil {
		return
	}

	err = json.Unmarshal(result, &gc)
	if err != nil {
		return
	}

	return
}

func getFile(url string) ([]byte, error) {
	resp, err := http.Get(url)
	if err != nil {
		return nil, err
	}
	data, err := ioutil.ReadAll(resp.Body)
	if err != nil {
		return nil, err
	}

	return data, nil
}

func getLanguages() (langs []string) {
	data, err := getFile("http://generator.swagger.io/api/gen/clients")
	if err != nil {
		log.Fatalf("Failed to load swagger languages: %v", err)
		os.Exit(-1)
	}

	err = json.Unmarshal(data, &langs)
	if err != nil {
		log.Fatalf("Failed to load swagger languages: %v", err)
		os.Exit(-1)
	}

	return
}

type GistFile struct {
	Content string `json:"content"`
}

type Gist struct {
	Description string              `json:"description"`
	Public      bool                `json:"public"`
	Files       map[string]GistFile `json:"files"`
}

type GistResponse struct {
	Files map[string]struct {
		RawURL string `json:"raw_url"`
	} `json:"files"`
}

func createGist(b []byte) string {
	var responseObj GistResponse

	gist := Gist{
		"",
		false,
		map[string]GistFile{
			"swaggerSpec": {string(b)},
		},
	}

	b, err := json.Marshal(gist)
	if err != nil {
		log.Fatal("JSON Error: ", err)
	}

	br := bytes.NewBuffer(b)
	resp, err := http.Post("https://api.github.com/gists", "application/json", br)
	if err != nil {
		log.Fatal("HTTP Error: ", err)
	}

	err = json.NewDecoder(resp.Body).Decode(&responseObj)
	if err != nil {
		log.Fatal("Response JSON Error: ", err)
	}

	return responseObj.Files["swaggerSpec"].RawURL
}

const (
	goSwaggerImage = "quay.io/goswagger/swagger"
)

func genSwaggerClient(target string) error {
	u, err := user.Current()
	if err != nil {
		return err
	}

	cmd := exec.Command("docker", "run", "--rm", "-u", fmt.Sprintf("%s:%s", u.Uid, u.Gid), "-v", fmt.Sprintf("%s/%s:/go/src/github.com/funcy/functions_go", cwd, target), "-v", fmt.Sprintf("%s/%s:/go/swagger.spec", cwd, swaggerURL), "-w", "/go/src", "quay.io/goswagger/swagger", "generate", "client", "-f", "/go/swagger.spec", "-t", "github.com/funcy/functions_go", "-A", "functions")
	d, err := cmd.CombinedOutput()
	if err != nil {
		log.Printf("Error running go-swagger: %s\n", d)
		return err
	}

	return nil
}