package main

import (
	"encoding/json"
	"fmt"
	"io"
	"net/http"
	"os"
	"regexp"
	"sort"
)

type JF2Response struct {
	Children []map[string]interface{} `json:"children"`
}

func mustEnv(key string) string {
	v := os.Getenv(key)
	if v == "" {
		fmt.Fprintf(os.Stderr, "missing env: %s\n", key)
		os.Exit(1)
	}
	return v
}

func main() {
	token := mustEnv("WEBMENTION_IO_TOKEN")
	domain := mustEnv("WEBMENTION_IO_DOMAIN")

	var all []map[string]interface{}
	client := &http.Client{}
	page := 0

	for {
		url := fmt.Sprintf(
			"https://webmention.io/api/mentions.jf2?domain=%s&token=%s&page=%d",
			domain, token, page,
		)

		resp, err := client.Get(url)
		if err != nil {
			panic(err)
		}
		body, _ := io.ReadAll(resp.Body)
		resp.Body.Close()

		var jf2 JF2Response
		if err := json.Unmarshal(body, &jf2); err != nil {
			panic(err)
		}

		if len(jf2.Children) == 0 {
			break
		}

		all = append(all, jf2.Children...)
		page++
	}

	reDomain := regexp.MustCompile(`^https?://[^/]+`)

	for _, c := range all {
		if t, ok := c["wm-target"].(string); ok {
			c["wm-target"] = reDomain.ReplaceAllString(t, "")
		}
	}

	sort.Slice(all, func(i, j int) bool {
		ti, _ := all[i]["wm-target"].(string)
		tj, _ := all[j]["wm-target"].(string)
		return ti < tj
	})

	grouped := map[string][]map[string]interface{}{}

	for _, c := range all {
		target, _ := c["wm-target"].(string)

		item := map[string]interface{}{
			"type":      c["wm-property"],
			"author":    c["author"],
			"url":       c["url"],
			"source":    c["wm-source"],
			"published": c["published"],
			"received":  c["wm-received"],
			"content":   c["content"],
		}

		grouped[target] = append(grouped[target], item)
	}

	if err := os.MkdirAll("data", 0755); err != nil {
		panic(err)
	}

	out, _ := json.MarshalIndent(grouped, "", "  ")
	if err := os.WriteFile("data/webmentions.json", out, 0644); err != nil {
		panic(err)
	}
}