// Copyright (C) 2024  Umorpha Systems
// SPDX-License-Identifier: AGPL-3.0-or-later

package main

import (
	"encoding/json"
	"errors"
	"html/template"
	"io"
	"log"
	"net/http"
	"os/exec"
	"sort"
)

type Webhooks struct {
	cfgFile string
}

func (o *Webhooks) ServeHTTP(w http.ResponseWriter, r *http.Request) {
	if err := o.serveHTTP(w, r); err != nil {
		if err.Code != -100 {
			http.Error(w, err.Error(), err.Code)
		}
		if err.Code/100 == 5 {
			log.Printf("error: %q: %v", r.URL, err)
		}
	}
}

var webhooks = map[string]func(cfg *Webhooks, w http.ResponseWriter, r *http.Request) *_httpError{
	"from-gitea": func(cfg *Webhooks, w http.ResponseWriter, r *http.Request) *_httpError {
		if r.Method != http.MethodPost {
			return httpError(errors.New("only POST is supported"), http.StatusMethodNotAllowed)
		}
		// TODO: Validate API key
		payloadBytes, err := io.ReadAll(r.Body)
		if err != nil {
			return httpError(err, http.StatusBadRequest)
		}
		var payload struct {
			Repository struct {
				SSHURL   string `json:"ssh_url"`
				CloneURL string `json:"clone_url"`
			} `json:"repository"`
		}
		if err := json.Unmarshal(payloadBytes, &payload); err != nil {
			return httpError(err, http.StatusBadRequest)
		}

		cmd := exec.CommandContext(r.Context(), "eclipse-trigger",
			"--config="+cfg.cfgFile,
			"--",
			payload.Repository.SSHURL,
			payload.Repository.CloneURL)
		cmd.Stdout = w
		cmd.Stderr = w
		if err := cmd.Run(); err != nil {
			return httpError(err, http.StatusInternalServerError)
		}
		return nil
	},
}

var tmplWebhooks = template.Must(template.ParseFS(tmplFS, "html/pages/webhooks.html.tmpl", "html/lib/*.html.tmpl"))

func (o *Webhooks) serveHTTP(w http.ResponseWriter, r *http.Request) *_httpError {
	if r.URL.Path == "" {
		if r.Method != http.MethodGet {
			return httpError(errors.New("only GET is supported"), http.StatusMethodNotAllowed)
		}
		names := make([]string, 0, len(webhooks))
		for name := range webhooks {
			names = append(names, name)
		}
		sort.Strings(names)
		if err := tmplWebhooks.Execute(w, map[string]any{"Webhooks": names}); err != nil {
			return writeOrServerError(err)
		}
	}
	callback := webhooks[r.URL.Path]
	if callback == nil {
		return httpNotFound()
	}
	return callback(o, w, r)
}