package handler

import (
	"net/http"
	"strconv"
	"strings"

	"github.com/go-chi/chi/v5"
	"github.com/prabhupadasays/spsays-bff/internal/repository"
	"github.com/prabhupadasays/spsays-bff/pkg/response"
)

type TranscriptionHandler struct {
	repo *repository.TranscriptionRepo
}

func NewTranscriptionHandler(repo *repository.TranscriptionRepo) *TranscriptionHandler {
	return &TranscriptionHandler{repo: repo}
}

func (h *TranscriptionHandler) GetBySlug(w http.ResponseWriter, r *http.Request) {
	slug := chi.URLParam(r, "slug")
	doc, err := h.repo.GetBySlug(r.Context(), slug)
	if err != nil {
		response.Error(w, http.StatusInternalServerError, "failed to fetch transcription")
		return
	}
	if doc == nil {
		response.Error(w, http.StatusNotFound, "transcription not found")
		return
	}
	response.JSON(w, http.StatusOK, doc)
}

func (h *TranscriptionHandler) GetByYear(w http.ResponseWriter, r *http.Request) {
	yearStr := chi.URLParam(r, "year")
	year, err := strconv.Atoi(yearStr)
	if err != nil {
		response.Error(w, http.StatusBadRequest, "invalid year")
		return
	}
	docs, err := h.repo.GetByYear(r.Context(), year)
	if err != nil {
		response.Error(w, http.StatusInternalServerError, "failed to fetch transcriptions")
		return
	}
	response.JSON(w, http.StatusOK, docs)
}

func (h *TranscriptionHandler) GetByPlace(w http.ResponseWriter, r *http.Request) {
	place := chi.URLParam(r, "place")
	docs, err := h.repo.GetByPlace(r.Context(), place)
	if err != nil {
		response.Error(w, http.StatusInternalServerError, "failed to fetch transcriptions")
		return
	}
	response.JSON(w, http.StatusOK, docs)
}

func (h *TranscriptionHandler) GetByType(w http.ResponseWriter, r *http.Request) {
	docType := chi.URLParam(r, "type")
	if docType != "lecture" && docType != "conversation" {
		response.Error(w, http.StatusBadRequest, "invalid type: must be 'lecture' or 'conversation'")
		return
	}
	docs, err := h.repo.GetByType(r.Context(), docType)
	if err != nil {
		response.Error(w, http.StatusInternalServerError, "failed to fetch transcriptions")
		return
	}
	response.JSON(w, http.StatusOK, docs)
}

func (h *TranscriptionHandler) GetBooks(w http.ResponseWriter, r *http.Request) {
	docs, err := h.repo.GetBooks(r.Context())
	if err != nil {
		response.Error(w, http.StatusInternalServerError, "failed to fetch books")
		return
	}
	response.JSON(w, http.StatusOK, docs)
}

func (h *TranscriptionHandler) GetByBook(w http.ResponseWriter, r *http.Request) {
	code := strings.ToUpper(chi.URLParam(r, "book"))
	if h.repo.BookTitle(code) == "" {
		response.Error(w, http.StatusNotFound, "unknown book")
		return
	}
	docs, err := h.repo.GetByBook(r.Context(), code)
	if err != nil {
		response.Error(w, http.StatusInternalServerError, "failed to fetch transcriptions")
		return
	}
	response.JSON(w, http.StatusOK, docs)
}

func (h *TranscriptionHandler) GetYears(w http.ResponseWriter, r *http.Request) {
	docs, err := h.repo.GetYears(r.Context())
	if err != nil {
		response.Error(w, http.StatusInternalServerError, "failed to fetch years")
		return
	}
	response.JSON(w, http.StatusOK, docs)
}

func (h *TranscriptionHandler) GetPlaces(w http.ResponseWriter, r *http.Request) {
	docs, err := h.repo.GetPlaces(r.Context())
	if err != nil {
		response.Error(w, http.StatusInternalServerError, "failed to fetch places")
		return
	}
	response.JSON(w, http.StatusOK, docs)
}

func (h *TranscriptionHandler) GetTypeDistribution(w http.ResponseWriter, r *http.Request) {
	lectures, conversations, err := h.repo.GetTypeDistribution(r.Context())
	if err != nil {
		response.Error(w, http.StatusInternalServerError, "failed to fetch type distribution")
		return
	}
	response.JSON(w, http.StatusOK, map[string]int64{
		"lectures":      lectures,
		"conversations": conversations,
	})
}

func (h *TranscriptionHandler) Count(w http.ResponseWriter, r *http.Request) {
	count, err := h.repo.Count(r.Context())
	if err != nil {
		response.Error(w, http.StatusInternalServerError, "failed to count transcriptions")
		return
	}
	response.JSON(w, http.StatusOK, map[string]int64{"count": count})
}

func (h *TranscriptionHandler) GetAdjacent(w http.ResponseWriter, r *http.Request) {
	slug := chi.URLParam(r, "slug")
	yearStr := r.URL.Query().Get("year")
	year, err := strconv.Atoi(yearStr)
	if err != nil {
		response.Error(w, http.StatusBadRequest, "invalid year")
		return
	}
	prev, next, err := h.repo.GetAdjacent(r.Context(), slug, year)
	if err != nil {
		response.Error(w, http.StatusInternalServerError, "failed to fetch adjacent transcriptions")
		return
	}
	response.JSON(w, http.StatusOK, map[string]interface{}{
		"prev": prev,
		"next": next,
	})
}