package ss

import (
	"io"
	"strings"
	"encoding/json"
	"net/http"
	"net/url"
	"fmt"
	"surdeus.su/core/ss/contents"
	"surdeus.su/core/ss/urlenc"
)

type Context struct {
	R *Request
	RelUrl *url.URL
	W ResponseWriter
	// Custom data to store stuff.
	Data any

	scanErr error
	dec     Decoder
}

func (c *Context) Method() ReqMethod {
	return ReqMethod(c.R.Method)
}

// Set the reply status code.
func (c *Context) SetStatus(status Status) {
	c.W.WriteHeader(int(status))
}

// Set the reply content type.
func (c *Context) SetContentType(typ contents.Type, opts ...contents.Option) {
	ret := string(typ)
	for _, opt := range opts {
		kv := opt.KeyValue()
		ret += ";"+kv[0]+"="+kv[1]
	}
	c.SetHeader("Content-Type", ret)
}

// Get the request content type.
func (c *Context) ContentType() contents.Type {
	ret, ok := c.Header("Content-Type")
	if !ok {
		return ""
	}
	if len(ret) < 1 {
		return ""
	}
	splits := strings.SplitN(ret[0], ";", 2)
	if len(splits) < 0 {
		return ""
	}
	return contents.Type(splits[0])
}

func (c *Context) SetHeader(k, v string) {
	c.W.Header().Set(k, v)
}

func (c *Context) Header(name string) ([]string, bool) {
	ret, ok := c.R.Header[name]
	return ret, ok
}

// Closes the requests body after finishes scaning.
func (c *Context) Close() {
	c.R.Body.Close()
}

// Scan the incoming value from body depending
// on the content type of the request into the
// structure or map[string] any.
func (c *Context) Scan(v any) bool {
	if c.dec == nil {
		typ := c.ContentType()
		switch typ {
		case contents.Json:
			c.dec = json.NewDecoder(c.R.Body)
		case contents.UrlEncoded:
			body, _ := io.ReadAll(c.R.Body)
			err := urlenc.Unmarshal(body, v)
			if err != nil {
				c.scanErr = err
			}
			return false
		default:
			c.scanErr = UnknownContentTypeErr
			return false
		}
	}

	err := c.dec.Decode(v)
	if err != nil {
		if err != io.EOF {
			c.scanErr = err
		}
		return false
	}
	return true
}

func (c *Context) ScanErr() error {
	return c.scanErr
}

func (c *Context) AbsPath() string {
	return c.R.URL.Path
}

func (c *Context) PathPrefix() string {
	pth := c.AbsPath()
	rpth := c.Path()
	return pth[:len(pth)-len(rpth)]
}

func (c *Context) Path() string {
	return c.RelUrl.Path
}

func (c *Context) NotFound() {
	http.NotFound(c.W, c.R)
}

func (c *Context) InternalServerError(err error) {
	c.W.WriteHeader(http.StatusInternalServerError)
	if err != nil {
		c.Printf("500 Internal Server Error: %q", err)
	} else {
	}
}

func (c *Context) Print(v ...any) (int, error) {
	return fmt.Print(v...)
}

func (c *Context) Printf(format string, v ...any) (int, error) {
	return fmt.Fprintf(c.W, format, v...)
}

func (c *Context) Query() url.Values {
	return c.R.URL.Query()
}

func (c *Context) Redirect(u string, status Status) {
	pth := c.AbsPath()
	if len(pth) > 0 && pth[len(pth)-1] != '/' {
		pth += "/"
	}
	c.R.URL.Path = pth
	http.Redirect(c.W, c.R, u, int(status))
}