package httpapi

import (
	"errors"
	"net/http"

	"github.com/descrybe/descrybe-v2/apps/api/internal/billing"
	"github.com/descrybe/descrybe-v2/apps/api/internal/processing"
	"github.com/go-chi/chi/v5"
	"github.com/google/uuid"
)

// startProcessingJobRequest is the SPA/API body for POST /processing/jobs.
// ProcessingTypes is accepted because the dashboard sends fine-grained types
// alongside the coarse ProcessingType used by StartJob; DecodeJSON rejects unknowns.
type startProcessingJobRequest struct {
	RawProductIDs   []string `json:"raw_product_ids"`
	ProcessingType  string   `json:"processing_type"`
	ProcessingTypes []string `json:"processing_types"`
}

func (s *Server) handleStartProcessingJob(w http.ResponseWriter, r *http.Request) {
	cid, ok := CompanyIDFromContext(r.Context())
	if !ok || cid == uuid.Nil {
		Error(w, http.StatusUnauthorized, "unauthorized")
		return
	}
	uid, _ := UserIDFromContext(r.Context())
	var body startProcessingJobRequest
	if err := DecodeJSON(r, &body); err != nil {
		Error(w, http.StatusBadRequest, "invalid json")
		return
	}
	ids := make([]uuid.UUID, 0, len(body.RawProductIDs))
	for _, sID := range body.RawProductIDs {
		id, err := uuid.Parse(sID)
		if err != nil {
			Error(w, http.StatusBadRequest, "invalid raw_product_id")
			return
		}
		ids = append(ids, id)
	}
	jobs, err := s.Processing.StartJob(r.Context(), cid, uid, ids, body.ProcessingType)
	if err != nil {
		if writePlanGate(w, err) {
			return
		}
		if errors.Is(err, processing.ErrRateLimited) {
			Error(w, http.StatusTooManyRequests, err.Error())
			return
		}
		if msg, ok := processing.ClientError(err); ok {
			Error(w, http.StatusBadRequest, msg)
			return
		}
		LogAndError(w, http.StatusBadRequest, "could not start processing job", err)
		return
	}
	for _, job := range jobs {
		if err := s.Jobs.EnqueueProcessingJob(r.Context(), job.ID); err != nil {
			Error(w, http.StatusInternalServerError, "enqueue failed")
			return
		}
	}
	JSON(w, http.StatusAccepted, processing.FormatStartJobsResponse(jobs))
}

func planGateCode(err error) string {
	switch {
	case errors.Is(err, billing.ErrInsufficientCredits):
		return "insufficient_credits"
	case errors.Is(err, billing.ErrProductLimitExceeded):
		return "product_limit"
	case errors.Is(err, billing.ErrAIRequiresUpgrade):
		return "ai_requires_upgrade"
	case errors.Is(err, billing.ErrEPRELRequiresUpgrade):
		return "eprel_requires_upgrade"
	case errors.Is(err, billing.ErrFeatureDisabled):
		return "plan_gate"
	default:
		return "plan_gate"
	}
}

func (s *Server) handleListProcessingJobs(w http.ResponseWriter, r *http.Request) {
	cid, ok := CompanyIDFromContext(r.Context())
	if !ok || cid == uuid.Nil {
		Error(w, http.StatusUnauthorized, "unauthorized")
		return
	}
	limit, _ := ParseLimitOffset(r)
	items, err := s.Processing.ListJobs(r.Context(), cid, limit)
	if err != nil {
		Error(w, http.StatusInternalServerError, "list failed")
		return
	}
	JSON(w, http.StatusOK, map[string]any{"jobs": processing.FormatListJobsResponse(items), "limit": limit})
}

func (s *Server) handleGetProcessingJob(w http.ResponseWriter, r *http.Request) {
	cid, ok := CompanyIDFromContext(r.Context())
	if !ok || cid == uuid.Nil {
		Error(w, http.StatusUnauthorized, "unauthorized")
		return
	}
	id, err := uuid.Parse(chi.URLParam(r, "id"))
	if err != nil {
		Error(w, http.StatusBadRequest, "invalid id")
		return
	}
	job, err := s.getV1ProcessJob(r.Context(), cid, id)
	if err != nil {
		Error(w, http.StatusNotFound, "not found")
		return
	}
	if processing.JobStatusIncludesProducts(job.Status) {
		items, loadErr := s.loadV1ProcessJobItems(r.Context(), cid, id, job.ProcessingType)
		if loadErr != nil {
			Error(w, http.StatusInternalServerError, "load failed")
			return
		}
		JSON(w, http.StatusOK, processing.FormatJobStatusResponse(job, items, true))
		return
	}
	JSON(w, http.StatusOK, job)
}

func (s *Server) handleCancelProcessingJob(w http.ResponseWriter, r *http.Request) {
	cid, ok := CompanyIDFromContext(r.Context())
	if !ok || cid == uuid.Nil {
		Error(w, http.StatusUnauthorized, "unauthorized")
		return
	}
	id, err := uuid.Parse(chi.URLParam(r, "id"))
	if err != nil {
		Error(w, http.StatusBadRequest, "invalid id")
		return
	}
	job, err := s.Processing.CancelJob(r.Context(), cid, id)
	if err != nil {
		if msg, ok := processing.ClientError(err); ok {
			Error(w, http.StatusBadRequest, msg)
			return
		}
		LogAndError(w, http.StatusBadRequest, "could not cancel job", err)
		return
	}
	JSON(w, http.StatusOK, job)
}

func (s *Server) handleRetryProcessingJob(w http.ResponseWriter, r *http.Request) {
	cid, ok := CompanyIDFromContext(r.Context())
	if !ok || cid == uuid.Nil {
		Error(w, http.StatusUnauthorized, "unauthorized")
		return
	}
	id, err := uuid.Parse(chi.URLParam(r, "id"))
	if err != nil {
		Error(w, http.StatusBadRequest, "invalid id")
		return
	}
	job, err := s.Processing.RetryJob(r.Context(), cid, id)
	if err != nil {
		if writePlanGate(w, err) {
			return
		}
		if errors.Is(err, processing.ErrRateLimited) {
			Error(w, http.StatusTooManyRequests, err.Error())
			return
		}
		if msg, ok := processing.ClientError(err); ok {
			Error(w, http.StatusBadRequest, msg)
			return
		}
		LogAndError(w, http.StatusBadRequest, "could not retry job", err)
		return
	}
	if err := s.Jobs.EnqueueProcessingJob(r.Context(), job.ID); err != nil {
		Error(w, http.StatusInternalServerError, "enqueue failed")
		return
	}
	JSON(w, http.StatusAccepted, job)
}