package api

import (
	"fmt"
	"net/http"

	"github.com/gin-gonic/gin"
	swaggerFiles "github.com/swaggo/files"
	ginSwagger "github.com/swaggo/gin-swagger"
)

// RegisterSwaggerHandlers serves the OpenAPI spec and an interactive Swagger UI
// (embedded swagger-ui-dist assets, no CDN) under /api.
func RegisterSwaggerHandlers(router *gin.Engine) error {
	spec, err := GetSwagger()
	if err != nil {
		return fmt.Errorf("error on building swagger specification: %w", err)
	}
	specBody, err := spec.MarshalJSON()
	if err != nil {
		return fmt.Errorf("error on marshaling swagger specification: %w", err)
	}

	// /api/docs/*any (rather than /api/*any) so this wildcard doesn't collide with
	// the static /api/openapi.json route at the same tree level.
	router.GET("/api/openapi.json", func(c *gin.Context) {
		c.Data(http.StatusOK, "application/json", specBody)
	})
	router.GET("/api", func(c *gin.Context) {
		c.Redirect(http.StatusFound, "/api/docs/index.html")
	})
	router.GET("/docs", func(c *gin.Context) {
		c.Redirect(http.StatusFound, "/api/docs/index.html")
	})
	router.GET("/api/docs/*any", ginSwagger.WrapHandler(swaggerFiles.Handler, ginSwagger.URL("/api/openapi.json")))

	return nil
}