package api

import (
	"database/sql"
	"fmt"
	"log"
	"net/http"
	"time"

	"git.hatecomputers.club/hatecomputers/hatecomputers.club/adapters/cloudflare"
	"git.hatecomputers.club/hatecomputers/hatecomputers.club/args"
	"git.hatecomputers.club/hatecomputers/hatecomputers.club/database"
	"git.hatecomputers.club/hatecomputers/hatecomputers.club/utils"
)

type RequestContext struct {
	DBConn *sql.DB
	Args   *args.Arguments

	Id    string
	Start time.Time

	TemplateData *map[string]interface{}
	User         *database.User
}

type FormError struct {
	Errors []string
}

type Continuation func(*RequestContext, *http.Request, http.ResponseWriter) ContinuationChain
type ContinuationChain func(Continuation, Continuation) ContinuationChain

func LogRequestContinuation(context *RequestContext, req *http.Request, resp http.ResponseWriter) ContinuationChain {
	return func(success Continuation, _failure Continuation) ContinuationChain {
		context.Start = time.Now()
		context.Id = utils.RandomId()

		log.Println(req.Method, req.URL.Path, req.RemoteAddr, context.Id)
		return success(context, req, resp)
	}
}

func LogExecutionTimeContinuation(context *RequestContext, req *http.Request, resp http.ResponseWriter) ContinuationChain {
	return func(success Continuation, _failure Continuation) ContinuationChain {
		end := time.Now()

		log.Println(context.Id, "took", end.Sub(context.Start))

		return success(context, req, resp)
	}
}

func HealthCheckContinuation(context *RequestContext, req *http.Request, resp http.ResponseWriter) ContinuationChain {
	return func(success Continuation, _failure Continuation) ContinuationChain {
		resp.WriteHeader(200)
		resp.Write([]byte("healthy"))
		return success(context, req, resp)
	}
}

func FailurePassingContinuation(context *RequestContext, req *http.Request, resp http.ResponseWriter) ContinuationChain {
	return func(_success Continuation, failure Continuation) ContinuationChain {
		return failure(context, req, resp)
	}
}

func IdContinuation(context *RequestContext, req *http.Request, resp http.ResponseWriter) ContinuationChain {
	return func(success Continuation, _failure Continuation) ContinuationChain {
		return success(context, req, resp)
	}
}

func CacheControlMiddleware(next http.Handler, maxAge int) http.Handler {
	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		header := fmt.Sprintf("public, max-age=%d", maxAge)
		w.Header().Set("Cache-Control", header)
		next.ServeHTTP(w, r)
	})
}

func MakeServer(argv *args.Arguments, dbConn *sql.DB) *http.Server {
	mux := http.NewServeMux()

	fileServer := http.FileServer(http.Dir(argv.StaticPath))
	mux.Handle("GET /static/", http.StripPrefix("/static/", CacheControlMiddleware(fileServer, 3600)))

	cloudflareAdapter := &cloudflare.CloudflareExternalDNSAdapter{
		APIToken: argv.CloudflareToken,
		ZoneId:   argv.CloudflareZone,
	}

	makeRequestContext := func() *RequestContext {
		return &RequestContext{
			DBConn:       dbConn,
			Args:         argv,
			TemplateData: &map[string]interface{}{},
		}
	}

	mux.HandleFunc("GET /", func(w http.ResponseWriter, r *http.Request) {
		requestContext := makeRequestContext()
		LogRequestContinuation(requestContext, r, w)(VerifySessionContinuation, FailurePassingContinuation)(IdContinuation, IdContinuation)(TemplateContinuation("home.html", true), FailurePassingContinuation)(LogExecutionTimeContinuation, LogExecutionTimeContinuation)(IdContinuation, IdContinuation)
	})

	mux.HandleFunc("GET /health", func(w http.ResponseWriter, r *http.Request) {
		requestContext := makeRequestContext()
		LogRequestContinuation(requestContext, r, w)(HealthCheckContinuation, FailurePassingContinuation)(LogExecutionTimeContinuation, LogExecutionTimeContinuation)(IdContinuation, IdContinuation)
	})

	mux.HandleFunc("GET /login", func(w http.ResponseWriter, r *http.Request) {
		requestContext := makeRequestContext()
		LogRequestContinuation(requestContext, r, w)(StartSessionContinuation, FailurePassingContinuation)(LogExecutionTimeContinuation, LogExecutionTimeContinuation)(IdContinuation, IdContinuation)
	})

	mux.HandleFunc("GET /auth", func(w http.ResponseWriter, r *http.Request) {
		requestContext := makeRequestContext()
		LogRequestContinuation(requestContext, r, w)(InterceptOauthCodeContinuation, FailurePassingContinuation)(LogExecutionTimeContinuation, LogExecutionTimeContinuation)(IdContinuation, IdContinuation)
	})

	mux.HandleFunc("GET /logout", func(w http.ResponseWriter, r *http.Request) {
		requestContext := makeRequestContext()
		LogRequestContinuation(requestContext, r, w)(LogoutContinuation, FailurePassingContinuation)(LogExecutionTimeContinuation, LogExecutionTimeContinuation)(IdContinuation, IdContinuation)
	})

	mux.HandleFunc("GET /dns", func(w http.ResponseWriter, r *http.Request) {
		requestContext := makeRequestContext()
		LogRequestContinuation(requestContext, r, w)(VerifySessionContinuation, FailurePassingContinuation)(ListDNSRecordsContinuation, GoLoginContinuation)(TemplateContinuation("dns.html", true), FailurePassingContinuation)(LogExecutionTimeContinuation, LogExecutionTimeContinuation)(IdContinuation, IdContinuation)
	})

	mux.HandleFunc("POST /dns", func(w http.ResponseWriter, r *http.Request) {
		requestContext := makeRequestContext()
		LogRequestContinuation(requestContext, r, w)(VerifySessionContinuation, FailurePassingContinuation)(ListDNSRecordsContinuation, GoLoginContinuation)(CreateDNSRecordContinuation(cloudflareAdapter), FailurePassingContinuation)(TemplateContinuation("dns.html", true), TemplateContinuation("dns.html", true))(LogExecutionTimeContinuation, LogExecutionTimeContinuation)(IdContinuation, IdContinuation)
	})

	mux.HandleFunc("POST /dns/delete", func(w http.ResponseWriter, r *http.Request) {
		requestContext := makeRequestContext()
		LogRequestContinuation(requestContext, r, w)(VerifySessionContinuation, FailurePassingContinuation)(DeleteDNSRecordContinuation(cloudflareAdapter), GoLoginContinuation)(LogExecutionTimeContinuation, LogExecutionTimeContinuation)(IdContinuation, IdContinuation)
	})

	mux.HandleFunc("GET /keys", func(w http.ResponseWriter, r *http.Request) {
		requestContext := makeRequestContext()
		LogRequestContinuation(requestContext, r, w)(VerifySessionContinuation, FailurePassingContinuation)(ListAPIKeysContinuation, GoLoginContinuation)(TemplateContinuation("api_keys.html", true), FailurePassingContinuation)(LogExecutionTimeContinuation, LogExecutionTimeContinuation)(IdContinuation, IdContinuation)
	})

	mux.HandleFunc("POST /keys", func(w http.ResponseWriter, r *http.Request) {
		requestContext := makeRequestContext()
		LogRequestContinuation(requestContext, r, w)(VerifySessionContinuation, FailurePassingContinuation)(CreateAPIKeyContinuation, GoLoginContinuation)(ListAPIKeysContinuation, ListAPIKeysContinuation)(TemplateContinuation("api_keys.html", true), TemplateContinuation("api_keys.html", true))(LogExecutionTimeContinuation, LogExecutionTimeContinuation)(IdContinuation, IdContinuation)
	})

	mux.HandleFunc("POST /keys/delete", func(w http.ResponseWriter, r *http.Request) {
		requestContext := makeRequestContext()
		LogRequestContinuation(requestContext, r, w)(VerifySessionContinuation, FailurePassingContinuation)(DeleteAPIKeyContinuation, GoLoginContinuation)(LogExecutionTimeContinuation, LogExecutionTimeContinuation)(IdContinuation, IdContinuation)
	})

	mux.HandleFunc("GET /guestbook", func(w http.ResponseWriter, r *http.Request) {
		requestContext := makeRequestContext()
		LogRequestContinuation(requestContext, r, w)(VerifySessionContinuation, FailurePassingContinuation)(CaptchaArgsContinuation, CaptchaArgsContinuation)(ListGuestbookContinuation, ListGuestbookContinuation)(TemplateContinuation("guestbook.html", true), FailurePassingContinuation)(LogExecutionTimeContinuation, LogExecutionTimeContinuation)(IdContinuation, IdContinuation)
	})

	mux.HandleFunc("POST /guestbook", func(w http.ResponseWriter, r *http.Request) {
		requestContext := makeRequestContext()
		LogRequestContinuation(requestContext, r, w)(VerifySessionContinuation, FailurePassingContinuation)(CaptchaVerificationContinuation, CaptchaVerificationContinuation)(SignGuestbookContinuation, FailurePassingContinuation)(ListGuestbookContinuation, ListGuestbookContinuation)(CaptchaArgsContinuation, CaptchaArgsContinuation)(TemplateContinuation("guestbook.html", true), TemplateContinuation("guestbook.html", true))(LogExecutionTimeContinuation, LogExecutionTimeContinuation)(IdContinuation, IdContinuation)
	})

	mux.HandleFunc("GET /{name}", func(w http.ResponseWriter, r *http.Request) {
		requestContext := makeRequestContext()
		name := r.PathValue("name")
		LogRequestContinuation(requestContext, r, w)(VerifySessionContinuation, FailurePassingContinuation)(IdContinuation, IdContinuation)(TemplateContinuation(name+".html", true), FailurePassingContinuation)(LogExecutionTimeContinuation, LogExecutionTimeContinuation)(IdContinuation, IdContinuation)
	})

	return &http.Server{
		Addr:    ":" + fmt.Sprint(argv.Port),
		Handler: mux,
	}
}