package httpapi

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

	"tutor/internal/config"
	"tutor/internal/interview"
	"tutor/internal/learnermemory"
	"tutor/internal/ontology"
	"tutor/internal/progression"
	"tutor/internal/teachingassets"
	"tutor/internal/webapp"
)

type Handler struct {
	cfg        config.Config
	diagnostic *interview.Service
	memory     *learnermemory.Service
	progress   *progression.Service
	ontology   *ontology.Service
	assets     *teachingassets.Service
}

func NewHandler(
	cfg config.Config,
	diagnostic *interview.Service,
	memory *learnermemory.Service,
	progress *progression.Service,
	ontology *ontology.Service,
	assets *teachingassets.Service,
) Handler {
	return Handler{
		cfg:        cfg,
		diagnostic: diagnostic,
		memory:     memory,
		progress:   progress,
		ontology:   ontology,
		assets:     assets,
	}
}

func (h Handler) Routes() http.Handler {
	mux := http.NewServeMux()
	mux.HandleFunc("GET /healthz", h.health)
	mux.HandleFunc("POST /api/v1/diagnostic-sessions", h.createDiagnosticSession)
	mux.HandleFunc("GET /api/v1/diagnostic-sessions/{id}", h.getDiagnosticSession)
	mux.HandleFunc("POST /api/v1/diagnostic-sessions/{id}/answers", h.submitDiagnosticAnswer)
	mux.HandleFunc("GET /api/v1/learners/{userID}/memory", h.getLearnerMemory)
	mux.HandleFunc("GET /api/v1/learners/{userID}/readiness-map", h.getReadinessMap)
	mux.HandleFunc("GET /api/v1/learners/{userID}/next-challenge", h.getNextChallenge)
	mux.HandleFunc("POST /api/v1/materials", h.ingestMaterial)
	mux.HandleFunc("GET /api/v1/ontology", h.getOntology)
	mux.HandleFunc("POST /api/v1/teaching-assets/prompts", h.generateTeachingAssetPrompt)
	mux.HandleFunc("GET /api/v1/teaching-assets", h.getTeachingAssets)
	mux.Handle("GET /", webapp.Handler())
	return mux
}

func (h Handler) health(w http.ResponseWriter, _ *http.Request) {
	writeJSON(w, http.StatusOK, healthResponse{
		Status:      "ok",
		Environment: h.cfg.Environment,
		ModelKey:    h.cfg.ModelKey,
	})
}

type healthResponse struct {
	Status      string `json:"status"`
	Environment string `json:"environment"`
	ModelKey    string `json:"model_key"`
}

func writeJSON(w http.ResponseWriter, status int, value any) {
	w.Header().Set("Content-Type", "application/json")
	w.WriteHeader(status)
	_ = json.NewEncoder(w).Encode(value)
}

func writeError(w http.ResponseWriter, status int, message string) {
	writeJSON(w, status, errorResponse{Error: message})
}

type errorResponse struct {
	Error string `json:"error"`
}