package api

import (
	"encoding/json"
	"errors"

	"srs.epita.fr/fic-server/libfic"

	"github.com/julienschmidt/httprouter"
)

func init() {
	router.GET("/api/exercices/", apiHandler(listExercices))

	router.GET("/api/exercices/:eid", apiHandler(exerciceHandler(showExercice)))
	router.PUT("/api/exercices/:eid", apiHandler(exerciceHandler(updateExercice)))
	router.DELETE("/api/exercices/:eid", apiHandler(exerciceHandler(deleteExercice)))

	router.GET("/api/exercices/:eid/files", apiHandler(exerciceHandler(listExerciceFiles)))
	router.POST("/api/exercices/:eid/files", apiHandler(exerciceHandler(createExerciceFile)))

	router.GET("/api/exercices/:eid/hints", apiHandler(exerciceHandler(listExerciceHints)))
	router.POST("/api/exercices/:eid/hints", apiHandler(exerciceHandler(createExerciceHint)))

	router.GET("/api/exercices/:eid/keys", apiHandler(exerciceHandler(listExerciceKeys)))
	router.POST("/api/exercices/:eid/keys", apiHandler(exerciceHandler(createExerciceKey)))
}

func listExercices(_ httprouter.Params, body []byte) (interface{}, error) {
	// List all exercices
	return fic.GetExercices()
}

func listExerciceFiles(exercice fic.Exercice, body []byte) (interface{}, error) {
	return exercice.GetFiles()
}

func listExerciceHints(exercice fic.Exercice, body []byte) (interface{}, error) {
	return exercice.GetHints()
}

func listExerciceKeys(exercice fic.Exercice, body []byte) (interface{}, error) {
	return exercice.GetKeys()
}

func showExercice(exercice fic.Exercice, body []byte) (interface{}, error) {
	return exercice, nil
}

func deleteExercice(exercice fic.Exercice, _ []byte) (interface{}, error) {
	return exercice.Delete()
}

func updateExercice(exercice fic.Exercice, body []byte) (interface{}, error) {
	var ue fic.Exercice
	if err := json.Unmarshal(body, &ue); err != nil {
		return nil, err
	}

	ue.Id = exercice.Id

	if len(ue.Title) == 0 {
		return nil, errors.New("Exercice's title not filled")
	}

	if _, err := ue.Update(); err != nil {
		return nil, err
	}

	return ue, nil
}

func createExercice(theme fic.Theme, body []byte) (interface{}, error) {
	// Create a new exercice
	var ue fic.Exercice
	if err := json.Unmarshal(body, &ue); err != nil {
		return nil, err
	}

	if len(ue.Title) == 0 {
		return nil, errors.New("Title not filled")
	}

	var depend *fic.Exercice = nil
	if ue.Depend != nil {
		if d, err := fic.GetExercice(*ue.Depend); err != nil {
			return nil, err
		} else {
			depend = &d
		}
	}

	return theme.AddExercice(ue.Title, ue.Statement, depend, ue.Gain, ue.VideoURI)
}

type uploadedKey struct {
	Name string
	Key  string
}

func createExerciceKey(exercice fic.Exercice, body []byte) (interface{}, error) {
	var uk uploadedKey
	if err := json.Unmarshal(body, &uk); err != nil {
		return nil, err
	}

	if len(uk.Key) == 0 {
		return nil, errors.New("Key not filled")
	}

	return exercice.AddRawKey(uk.Name, uk.Key)
}

func createExerciceHint(exercice fic.Exercice, body []byte) (interface{}, error) {
	var uh fic.EHint
	if err := json.Unmarshal(body, &uh); err != nil {
		return nil, err
	}

	if len(uh.Content) == 0 {
		return nil, errors.New("Hint's content not filled")
	}

	return exercice.AddHint(uh.Title, uh.Content, uh.Cost)
}