package handlers

import (
	"fmt"
	"io"
	"net/http"

	"devone.aplikasi.web.id/gitea/mario/go-ohif-proxy/internal/proxy"
	"github.com/gin-gonic/gin"
	"go.uber.org/zap"
)

// DicomHandler handles DICOM Web requests
type DicomHandler struct {
	client *proxy.Client
	logger *zap.Logger
}

// NewDicomHandler creates a new DICOM handler
func NewDicomHandler(client *proxy.Client, logger *zap.Logger) *DicomHandler {
	return &DicomHandler{
		client: client,
		logger: logger,
	}
}

// ForwardRequest forwards the request to Google Healthcare API
func (h *DicomHandler) ForwardRequest(c *gin.Context) {
	path := c.Param("path")
	requestType := getRequestType(c.Request.URL.Path)

	h.logger.Debug("Forwarding request",
		zap.String("path", path),
		zap.String("method", c.Request.Method),
		zap.String("type", requestType),
	)

	// Read request body if present
	var bodyBytes []byte
	if c.Request.Body != nil && c.Request.ContentLength > 0 {
		var err error
		bodyBytes, err = io.ReadAll(c.Request.Body)
		if err != nil {
			h.logger.Error("Failed to read request body", zap.Error(err))
			c.JSON(http.StatusInternalServerError, gin.H{"error": "Failed to read request body"})
			return
		}
	}

	// Get request headers
	headers := make(map[string]string)
	for k, v := range c.Request.Header {
		if len(v) > 0 {
			headers[k] = v[0]
		}
	}

	// Forward the request to Healthcare API
	response, err := h.client.ForwardRequest(
		c.Request.Context(),
		c.Request.Method,
		requestType,
		path,
		headers,
		bodyBytes,
	)

	if err != nil {
		h.logger.Error("Request forwarding failed", zap.Error(err))
		c.JSON(http.StatusInternalServerError, gin.H{"error": fmt.Sprintf("Request failed: %v", err)})
		return
	}

	// Set response headers
	for k, v := range response.Headers {
		c.Header(k, v)
	}

	// Set status and write response body
	c.Status(response.StatusCode)
	c.Writer.Write(response.Body)
}

// getRequestType determines if the request is WADO, QIDO or STOW
func getRequestType(path string) string {
	if len(path) < 9 {
		return "unknown"
	}

	pathComponent := path[9:] // Remove "/dicomWeb/"

	if len(pathComponent) >= 4 && pathComponent[:4] == "wado" {
		return "wado"
	} else if len(pathComponent) >= 4 && pathComponent[:4] == "qido" {
		return "qido"
	} else if len(pathComponent) >= 4 && pathComponent[:4] == "stow" {
		return "stow"
	}

	return "unknown"
}