package main

import (
	"context"
	"fmt"
	"strings"

	sr "tildegit.org/tjp/sliderule"
	"tildegit.org/tjp/sliderule/contrib/cgi"
	"tildegit.org/tjp/sliderule/contrib/fs"
	"tildegit.org/tjp/sliderule/gopher"
	"tildegit.org/tjp/sliderule/gopher/gophermap"
	"tildegit.org/tjp/sliderule/logging"
	"tildegit.org/tjp/syw"
)

func buildGopherServer(server Server, config *Configuration) (sr.Server, error) {
	addr := fmt.Sprintf("%s:%d", server.IP.String(), server.Port)

	_, info, _, errlog := Loggers(config)
	_ = info.Log("msg", "starting gopher server", "addr", addr)

	if server.TLS != nil {
		return gopher.NewTLSServer(
			context.Background(),
			server.Hostnames[0],
			"tcp",
			addr,
			logging.LogRequests(info)(routes(server)),
			errlog,
			server.TLS,
		)
	}

	return gopher.NewServer(
		context.Background(),
		server.Hostnames[0],
		"tcp",
		addr,
		logging.LogRequests(info)(routes(server)),
		errlog,
	)
}

func addGopherRoute(router *sr.Router, route RouteDirective) {
	switch route.Type {
	case "static":
		addGopherStaticRoute(router, route)
	case "cgi":
		addGopherCGIRoute(router, route)
	case "git":
		addGopherGitRoute(router, route)
	}
}

func addGopherStaticRoute(router *sr.Router, route RouteDirective) {
	dirmaps := []string{}
	if route.Modifiers.DirDefault != "" {
		dirmaps = append(dirmaps, route.Modifiers.DirDefault)
	}
	settings := &gophermap.FileSystemSettings{
		ParseExtended: route.Modifiers.ExtendedGophermap,
		Exec:          route.Modifiers.Exec,
		ListUsers:     false,
		DirMaps:       dirmaps,
	}

	buildAndAddRoute(router, route, func(route RouteDirective) sr.Handler {
		handlers := []sr.Handler{}

		if route.Modifiers.Exec {
			handlers = append(handlers, cgi.GopherCGIDirectory(route.FsPath, route.URLPath, route.Modifiers.ExecCmd, settings))
		}

		handlers = append(handlers, fs.GopherFileHandler(route.FsPath, route.URLPath, settings))

		if route.Modifiers.DirDefault != "" {
			handlers = append(handlers, fs.GopherDirectoryDefault(route.FsPath, route.URLPath, settings))
		}

		if route.Modifiers.DirList {
			handlers = append(handlers, fs.GopherDirectoryListing(route.FsPath, route.URLPath, settings))
		}

		if len(handlers) == 1 {
			return handlers[0]
		}
		return sr.FallthroughHandler(handlers...)
	})
}

func addGopherCGIRoute(router *sr.Router, route RouteDirective) {
	dirmaps := []string{}
	if route.Modifiers.DirDefault != "" {
		dirmaps = append(dirmaps, route.Modifiers.DirDefault)
	}
	settings := &gophermap.FileSystemSettings{
		ParseExtended: route.Modifiers.ExtendedGophermap,
		Exec:          true,
		ListUsers:     false,
		DirMaps:       dirmaps,
	}

	buildAndAddRoute(router, route, func(route RouteDirective) sr.Handler {
		return cgi.GopherCGIDirectory(route.FsPath, route.URLPath, route.Modifiers.ExecCmd, settings)
	})
}

func addGopherGitRoute(router *sr.Router, route RouteDirective) {
	buildAndAddRoute(router, route, func(route RouteDirective) sr.Handler {
		return sr.HandlerFunc(func(ctx context.Context, request *sr.Request) *sr.Response {
			subrouter := syw.GopherRouter(route.FsPath, route.Modifiers.Templates)

			reqclone := cloneRequest(request)
			reqclone.Path = strings.TrimPrefix(reqclone.Path, route.URLPath)

			handler, params := subrouter.Match(reqclone)
			if handler == nil {
				return nil
			}
			return handler.Handle(context.WithValue(ctx, sr.RouteParamsKey, params), request)
		})
	})
}

func cloneRequest(request *sr.Request) *sr.Request {
	r := *request
	u := *request.URL
	r.URL = &u
	return &r
}