package server

import (
	"encoding/json"
	"fmt"
	"net/http"

	"github.com/gorilla/mux"
)

func newContext(w http.ResponseWriter, r *http.Request, srv *Server) *Context {
	h := w.Header()
	h.Set("Content-Type", "application/json")
	return &Context{
		Status:   http.StatusOK,
		Request:  r,
		Response: w,
		s:        srv,
	}
}

// Context is the context object shared between http handlers
type Context struct {
	Body   []byte
	Status int

	Request  *http.Request
	Response http.ResponseWriter
	s        *Server
}

// Method returns the request method
func (c *Context) Method() string {
	return c.Request.Method
}

// GetHeader returns the given http header
func (c *Context) GetHeader(name string) string {
	return c.Request.Header.Get(name)
}

// SetHeader sets the given http header
func (c *Context) SetHeader(name, value string) {
	h := c.Response.Header()
	h.Set(name, value)
}

// Form returns the given form value
func (c *Context) Form(name string) string {
	return c.Request.FormValue(name)
}

// Var returns the given url variable
func (c *Context) Var(name string) (ret string) {
	ret, _ = mux.Vars(c.Request)[name]
	return
}

func (c *Context) log() {
	c.s.log.Info("access",
		"addr", c.Request.RemoteAddr,
		"method", c.Request.Method,
		"url", c.Request.URL,
		"status", c.Status,
	)
}

func (c *Context) NotFound() {
	c.Status = http.StatusNotFound
	c.Response.WriteHeader(http.StatusNotFound)
	c.Response.Write([]byte(`{"message":"not found","status":404}`))
	c.log()
}

// OK is a empty HTTP 200 JSON response
func (c *Context) OK() {
	c.Response.Write([]byte("{}"))
	c.log()
}

// JSON is a json response
func (c *Context) JSON(v interface{}) {
	err := json.NewEncoder(c.Response).Encode(v)
	if err != nil {
		c.Err(ise)
		return
	}
	c.log()
}

// Err is a HTTPErr wrapper for the custom Error type
func (c *Context) Err(err Error) {
	c.HTTPErr(err.Error(), err.Status())
}

// HTTPErr is a http.Error wrapper
func (c *Context) HTTPErr(err string, status int) {
	c.Status = status
	http.Error(c.Response, err, status)
	c.log()
}

type ctxHandler func(*Context)