package caddyhugo

import (
	"errors"
	"fmt"
	"html/template"
	"net/http"
	"os"
	"path"
	"path/filepath"
	"strings"

	"github.com/gorilla/websocket"
	"github.com/mholt/caddy"
	"github.com/mholt/caddy/caddyhttp/httpserver"
)

func init() {
	plugin := CaddyHugo{}

	// register a "generic" plugin, like a directive or middleware
	caddy.RegisterPlugin("hugo", caddy.Plugin{
		ServerType: "http",
		Action:     plugin.Setup,
	})

	// ... there are others. See the godoc.
}

type CaddyHugo struct {
	ServerType string
	Site       *httpserver.SiteConfig

	authorTmpl, adminTmpl, editTmpl *template.Template
}

func (ch CaddyHugo) Setup(c *caddy.Controller) error {

	ch.Site = httpserver.GetConfig(c)

	var err error

	ch.authorTmpl, err = template.New("").Parse(AuthorPage)
	if err != nil {
		return fmt.Errorf("author template invalid: %v", err)
	}

	ch.adminTmpl, err = template.New("").Parse(AdminPage)
	if err != nil {
		return fmt.Errorf("admin template invalid: %v", err)
	}

	ch.editTmpl, err = template.New("").Parse(EditPage)
	if err != nil {
		return fmt.Errorf("edit template invalid: %v", err)
	}

	// add a function that wraps listeners for the HTTP server
	// (it's more common for a directive to call this rather than a standalone plugin)
	ch.Site.AddMiddleware(ch.Middleware(c))

	return nil
}

func (ch CaddyHugo) Middleware(c *caddy.Controller) httpserver.Middleware {
	return func(h httpserver.Handler) httpserver.Handler {
		return httpserver.HandlerFunc(func(w http.ResponseWriter, r *http.Request) (int, error) {
			if !ch.Match(r) {
				return h.ServeHTTP(w, r)
			}

			if !ch.Auth(r) {
				return http.StatusUnauthorized, errors.New("not authorized")
			}

			if strings.HasPrefix(r.URL.Path, "/hugo/admin") {
				return ch.Admin().ServeHTTP(w, r)
			}
			if strings.HasPrefix(r.URL.Path, "/hugo/author") {
				return ch.AuthorHome().ServeHTTP(w, r)
			}
			if strings.HasPrefix(r.URL.Path, "/hugo/edit/") {
				return ch.Edit(c).ServeHTTP(w, r)
			}

			return http.StatusNotFound, errors.New("not found")
		})
	}
}

func (ch CaddyHugo) Auth(r *http.Request) bool {
	return true
}

func (ch CaddyHugo) Match(r *http.Request) bool {
	if r.URL.Path == "/hugo" {
		return true
	}

	return strings.HasPrefix(r.URL.Path, "/hugo/")
}

func (ch CaddyHugo) BasePath() string {
	return "/hugo"
}

func (ch CaddyHugo) Admin() httpserver.Handler {
	return httpserver.HandlerFunc(func(w http.ResponseWriter, r *http.Request) (int, error) {
		err := ch.adminTmpl.Execute(w, ch.TmplData(r))
		if err != nil {
			fmt.Println(err)
			return http.StatusInternalServerError, err
		}

		return http.StatusOK, nil

	})
}

func (ch CaddyHugo) AuthorHome() httpserver.Handler {
	return httpserver.HandlerFunc(func(w http.ResponseWriter, r *http.Request) (int, error) {
		err := ch.authorTmpl.Execute(w, ch.TmplData(r))
		if err != nil {
			fmt.Println(err)
			return http.StatusInternalServerError, err
		}

		return http.StatusOK, nil
	})
}

func (ch CaddyHugo) Edit(c *caddy.Controller) httpserver.Handler {
	return httpserver.HandlerFunc(func(w http.ResponseWriter, r *http.Request) (int, error) {
		if r.URL.Path == "/hugo/edit/new" {
			return ch.NewContent(w, r)
		}
		if r.URL.Path == "/hugo/edit/websocket" {
			return ch.DeltaWebsocket(w, r)
		}

		err := ch.editTmpl.Execute(w, ch.TmplData(r))
		if err != nil {

			fmt.Println(err)
			return http.StatusInternalServerError, err
		}

		return http.StatusOK, nil
	})
}

func (ch CaddyHugo) DeltaWebsocket(w http.ResponseWriter, r *http.Request) (int, error) {
	var upgrader = websocket.Upgrader{
		ReadBufferSize:  1024,
		WriteBufferSize: 1024,
	}

	conn, err := upgrader.Upgrade(w, r, nil)
	if err != nil {
		fmt.Println(err)
		return http.StatusBadRequest, err
	}

	for {
		messageType, p, err := conn.ReadMessage()
		if err != nil {
			return http.StatusBadRequest, err
		}

		fmt.Println(messageType, string(p))
	}
}

func (ch CaddyHugo) NewContent(w http.ResponseWriter, r *http.Request) (int, error) {
	name := r.FormValue("name")
	ctype := r.FormValue("type")

	if filepath.Ext(name) != ".md" {
		name += ".md"
	}

	filename := path.Join(ch.Site.Root, "content", ctype, name)

	dir := filepath.Dir(filename)
	if _, err := os.Stat(dir); err != nil && os.IsNotExist(err) {
		err = os.MkdirAll(dir, 0755)
		if err != nil {
			fmt.Println(err)
			return http.StatusInternalServerError, err
		}
	}

	// create content
	f, err := os.Create(filename)
	if err != nil && !os.IsExist(err) {
		fmt.Println(err)
		return http.StatusInternalServerError, err
	}

	// we only needed to make the file though
	err = f.Close()
	if err != nil {
		fmt.Println(err)
		return http.StatusInternalServerError, err
	}

	// serve redirect
	http.Redirect(w, r, filepath.Join("/hugo/edit/", filename), http.StatusFound)
	return http.StatusFound, nil
}

func (ch CaddyHugo) TmplData(r *http.Request) interface{} {
	return tmplData{ch.Site, r, ch}
}