package handlers

import (
	"net/http"
	"os"
	"strconv"

	"github.com/gin-gonic/gin"
	"github.com/google/uuid"
	"go.uber.org/zap"

	apperrors "veza-backend-api/internal/errors"
	"veza-backend-api/internal/models"
	"veza-backend-api/internal/services"
)

// LiveStreamHandler handles live stream HTTP requests
type LiveStreamHandler struct {
	service *services.LiveStreamService
	logger  *zap.Logger
}

// NewLiveStreamHandler creates a new LiveStreamHandler
func NewLiveStreamHandler(service *services.LiveStreamService, logger *zap.Logger) *LiveStreamHandler {
	return &LiveStreamHandler{service: service, logger: logger}
}

// CreateLiveStreamRequest represents the request body for creating a live stream
type CreateLiveStreamRequest struct {
	Title        string   `json:"title" binding:"required"`
	Description  string   `json:"description"`
	Category     string   `json:"category"`
	ThumbnailURL string   `json:"thumbnailUrl"`
	StreamerName string   `json:"streamer"`
	Tags         []string `json:"tags"`
}

// ListLiveStreams returns all live streams (public - optionally filter by is_live)
func (h *LiveStreamHandler) ListLiveStreams(c *gin.Context) {
	var isLive *bool
	if q := c.Query("is_live"); q != "" {
		b, err := strconv.ParseBool(q)
		if err == nil {
			isLive = &b
		}
	}
	streams, err := h.service.List(c.Request.Context(), isLive)
	if err != nil {
		RespondWithAppError(c, apperrors.Wrap(apperrors.ErrCodeInternal, "Failed to list streams", err))
		return
	}
	RespondSuccess(c, http.StatusOK, gin.H{"streams": streams})
}

// GetLiveStream returns a single live stream by ID
func (h *LiveStreamHandler) GetLiveStream(c *gin.Context) {
	id, err := uuid.Parse(c.Param("id"))
	if err != nil {
		RespondWithAppError(c, apperrors.NewValidationError("invalid stream ID"))
		return
	}
	stream, err := h.service.Get(c.Request.Context(), id)
	if err != nil {
		RespondWithAppError(c, apperrors.NewNotFoundError("stream not found"))
		return
	}
	RespondSuccess(c, http.StatusOK, gin.H{"stream": stream})
}

// CreateLiveStream creates a new live stream (requires auth)
func (h *LiveStreamHandler) CreateLiveStream(c *gin.Context) {
	userID, ok := GetUserIDUUID(c)
	if !ok {
		return
	}
	var req CreateLiveStreamRequest
	if appErr := NewCommonHandler(h.logger).BindAndValidateJSON(c, &req); appErr != nil {
		RespondWithAppError(c, appErr)
		return
	}
	stream := &models.LiveStream{
		Title:        req.Title,
		Description:  req.Description,
		Category:     req.Category,
		ThumbnailURL: req.ThumbnailURL,
		StreamerName: req.StreamerName,
		Tags:         req.Tags,
	}
	if stream.StreamerName == "" {
		stream.StreamerName = "Streamer"
	}
	created, err := h.service.Create(c.Request.Context(), userID, stream)
	if err != nil {
		RespondWithAppError(c, apperrors.Wrap(apperrors.ErrCodeInternal, "Failed to create stream", err))
		return
	}
	RespondSuccess(c, http.StatusCreated, gin.H{"stream": created})
}

// GetMyStreams returns the authenticated user's streams (including stream_key)
func (h *LiveStreamHandler) GetMyStreams(c *gin.Context) {
	userID, ok := GetUserIDUUID(c)
	if !ok {
		return
	}
	streams, err := h.service.ListByUser(c.Request.Context(), userID)
	if err != nil {
		RespondWithAppError(c, apperrors.Wrap(apperrors.ErrCodeInternal, "Failed to list streams", err))
		return
	}
	type streamWithKey struct {
		*models.LiveStream
		StreamKey string `json:"stream_key"`
	}
	result := make([]streamWithKey, len(streams))
	for i, s := range streams {
		result[i] = streamWithKey{LiveStream: s, StreamKey: s.StreamKey}
	}
	RespondSuccess(c, http.StatusOK, gin.H{"streams": result})
}

// GetMyStreamKey returns the user's stream key (creates draft if none exist)
func (h *LiveStreamHandler) GetMyStreamKey(c *gin.Context) {
	userID, ok := GetUserIDUUID(c)
	if !ok {
		return
	}
	streams, err := h.service.ListByUser(c.Request.Context(), userID)
	if err != nil {
		RespondWithAppError(c, apperrors.Wrap(apperrors.ErrCodeInternal, "Failed to get streams", err))
		return
	}
	var streamKey string
	if len(streams) > 0 {
		streamKey = streams[0].StreamKey
	} else {
		draft := &models.LiveStream{Title: "My Stream"}
		created, createErr := h.service.Create(c.Request.Context(), userID, draft)
		if createErr != nil {
			RespondWithAppError(c, apperrors.Wrap(apperrors.ErrCodeInternal, "Failed to create stream", createErr))
			return
		}
		streamKey = created.StreamKey
	}
	rtmpHost := os.Getenv("NGINX_RTMP_HOST")
	if rtmpHost == "" {
		rtmpHost = "stream.veza.app"
	}
	RespondSuccess(c, http.StatusOK, gin.H{
		"stream_key": streamKey,
		"rtmp_url":   "rtmp://" + rtmpHost + "/live",
	})
}

// RegenerateStreamKey generates a new stream key for the user's first stream
func (h *LiveStreamHandler) RegenerateStreamKey(c *gin.Context) {
	userID, ok := GetUserIDUUID(c)
	if !ok {
		return
	}
	streams, err := h.service.ListByUser(c.Request.Context(), userID)
	if err != nil || len(streams) == 0 {
		RespondWithAppError(c, apperrors.NewNotFoundError("no stream found"))
		return
	}
	newKey, err := h.service.RegenerateStreamKey(c.Request.Context(), streams[0].ID, userID)
	if err != nil {
		RespondWithAppError(c, apperrors.Wrap(apperrors.ErrCodeInternal, "Failed to regenerate key", err))
		return
	}
	rtmpHost := os.Getenv("NGINX_RTMP_HOST")
	if rtmpHost == "" {
		rtmpHost = "stream.veza.app"
	}
	RespondSuccess(c, http.StatusOK, gin.H{
		"stream_key": newKey,
		"rtmp_url":   "rtmp://" + rtmpHost + "/live",
	})
}

// UpdateLiveStream updates a live stream's metadata (ownership check)
func (h *LiveStreamHandler) UpdateLiveStream(c *gin.Context) {
	userID, ok := GetUserIDUUID(c)
	if !ok {
		return
	}
	id, err := uuid.Parse(c.Param("id"))
	if err != nil {
		RespondWithAppError(c, apperrors.NewValidationError("invalid stream ID"))
		return
	}
	var req CreateLiveStreamRequest
	if appErr := NewCommonHandler(h.logger).BindAndValidateJSON(c, &req); appErr != nil {
		RespondWithAppError(c, appErr)
		return
	}
	stream := &models.LiveStream{
		Title:        req.Title,
		Description:  req.Description,
		Category:     req.Category,
		ThumbnailURL: req.ThumbnailURL,
		StreamerName: req.StreamerName,
		Tags:         req.Tags,
	}
	updated, updateErr := h.service.Update(c.Request.Context(), id, userID, stream)
	if updateErr != nil {
		RespondWithAppError(c, apperrors.Wrap(apperrors.ErrCodeInternal, "Failed to update stream", updateErr))
		return
	}
	RespondSuccess(c, http.StatusOK, gin.H{"stream": updated})
}