package handler

import (
	"log"
	"strings"

	"gitea.loveuer.com/loveuer/cluster/controller"
	"gitea.loveuer.com/loveuer/cluster/internal/registry/storage"

	"github.com/gofiber/fiber/v3"
)

func isBlob(c fiber.Ctx) bool {
	elem := strings.Split(c.Path(), "/")
	elem = elem[1:]
	if elem[len(elem)-1] == "" {
		elem = elem[:len(elem)-1]
	}
	if len(elem) < 3 {
		return false
	}
	return elem[len(elem)-2] == "blobs" || (elem[len(elem)-3] == "blobs" &&
		elem[len(elem)-2] == "uploads")
}

func isManifest(c fiber.Ctx) bool {
	elems := strings.Split(c.Path(), "/")
	elems = elems[1:]
	if len(elems) < 4 {
		return false
	}
	return elems[len(elems)-2] == "manifests"
}

func isTags(c fiber.Ctx) bool {
	elems := strings.Split(c.Path(), "/")
	elems = elems[1:]
	if len(elems) < 4 {
		return false
	}
	return elems[len(elems)-2] == "tags"
}

func isCatalog(c fiber.Ctx) bool {
	elems := strings.Split(c.Path(), "/")
	elems = elems[1:]
	if len(elems) < 2 {
		return false
	}
	return elems[len(elems)-1] == "_catalog"
}

func isReferrers(c fiber.Ctx) bool {
	elems := strings.Split(c.Path(), "/")
	elems = elems[1:]
	if len(elems) < 4 {
		return false
	}
	return elems[len(elems)-2] == "referrers"
}

// RegistryV2 handles all OCI Registry API v2 requests
func RegistryV2(store storage.Storage) fiber.Handler {
	// Initialize handlers
	blobHandler = NewBlobHandler(store)
	uploadHandler = NewUploadHandler()
	m = NewManifestHandler(store)

	return func(c fiber.Ctx) error {
		if isBlob(c) {
			return handleBlobs(c)
		}

		if isManifest(c) {
			return handleManifest(c)
		}

		if isTags(c) {
			return handleTags(c)
		}

		if isCatalog(c) {
			return handleCatalog(c)
		}

		if isReferrers(c) {
			return handleReferrers(c)
		}

		// Handle root v2 endpoint
		if c.Path() == "/v2/" {
			c.Set("Docker-Distribution-API-Version", "registry/2.0")
			return c.SendStatus(200)
		}

		c.Set("Docker-Distribution-API-Version", "registry/2.0")

		log.Printf("[WARN] RegistryV2: unknown endpoint - path = %s, method = %s", c.Path(), c.Method())

		return c.Status(404).JSON(fiber.Map{
			"errors": []fiber.Map{{"code": "NOT_FOUND", "message": "endpoint not found"}},
		})
	}
}

// ListImages 返回所有仓库列表
func ListImages(c fiber.Ctx) error {
	repos, err := controller.ListImages()
	if err != nil {
		return c.Status(fiber.StatusInternalServerError).JSON(fiber.Map{"error": err.Error()})
	}
	return c.JSON(fiber.Map{"images": repos})
}