package main

import (
	"encoding/base64"
	"fmt"
	"math/rand"
	"net/http"

	"github.com/easonlin404/ksm"
	"github.com/easonlin404/ksm/d"
	"github.com/gin-gonic/gin"
	"github.com/gin-gonic/gin/binding"
)

func main() {

	r := gin.Default()

	type SpcMessage struct {
		Spc     string `json:"spc" binding:"required"`
		AssetId string `json:"assetId"`
	}

	r.POST("/fps/rest/getLicense", func(c *gin.Context) {
		var spcMessage SpcMessage
		if err := c.ShouldBindWith(&spcMessage, binding.JSON); err != nil {
			c.JSON(http.StatusBadRequest, gin.H{
				"err": err.Error(),
			})
			return
		}

		fmt.Printf("%v\n", spcMessage)

		playback, err := base64.StdEncoding.DecodeString(spcMessage.Spc)
		checkError(err)

		k := &ksm.Ksm{
			Pub:       pub,
			Pri:       pri,
			Rck:       RandomContentKey{},
			DFunction: d.AppleD{},
			Ask:       []byte{},
		}
		ckc, err2 := k.GenCKC(playback)
		checkError(err2)

		ckcBase64 := base64.StdEncoding.EncodeToString(ckc)
		c.JSON(http.StatusOK, gin.H{
			"ckc": ckcBase64,
		})
	})

	r.Run(":8080")

}

func checkError(err error) {
	if err != nil {
		panic(err)
	}
}

type RandomContentKey struct {
}

func (RandomContentKey) FetchContentKey(assetId []byte) ([]byte, []byte, error) {
	key := make([]byte, 16)
	iv := make([]byte, 16)
	rand.Read(key)
	rand.Read(iv)
	return key, iv, nil
}

func (RandomContentKey) FetchContentKeyDuration(assetId []byte) (*ksm.CkcContentKeyDurationBlock, error) {

	LeaseDuration := rand.Uint32()  // The duration of the lease, if any, in seconds.
	RentalDuration := rand.Uint32() // The duration of the rental, if any, in seconds.

	return ksm.NewCkcContentKeyDurationBlock(LeaseDuration, RentalDuration), nil
}