package notice

import (
	"crypto/hmac"
	"crypto/sha256"
	"encoding/base64"
	"fmt"
	"net/url"
	"strconv"
	"strings"
	"time"
)

type dingTalkRenderer struct{}

func (dingTalkRenderer) Capabilities() Capabilities {
	return Capabilities{Text: true, ColorText: true, Markdown: true, Card: true}
}

func (dingTalkRenderer) Render(config Config, message Message) (renderedRequest, error) {
	body := map[string]any{}
	switch message.Type {
	case MessageText:
		body = map[string]any{"msgtype": "text", "text": map[string]any{"content": message.Content}}
	case MessageColorText:
		body = dingTalkMarkdown("消息通知", dingTalkColorMarkdown(message.Segments))
	case MessageMarkdown:
		body = dingTalkMarkdown(plainTitle(message.Title, "消息通知"), message.Content)
	case MessageCard:
		content := cardMarkdown(message.Card)
		if strings.TrimSpace(content) == "" {
			content = message.Card.Title
		}
		if len(message.Card.Actions) == 0 {
			body = dingTalkMarkdown(plainTitle(message.Card.Title, "消息通知"), content)
			break
		}
		buttons := make([]any, 0, len(message.Card.Actions))
		for _, action := range message.Card.Actions {
			buttons = append(buttons, map[string]any{"title": action.Text, "actionURL": action.URL})
		}
		body = map[string]any{"msgtype": "actionCard", "actionCard": map[string]any{
			"title": plainTitle(message.Card.Title, "消息通知"), "text": content,
			"btnOrientation": "0", "btns": buttons,
		}}
	}
	webhook := config.Webhook
	secret := signatureSecret(config)
	if secret != "" {
		timestamp := strconv.FormatInt(time.Now().UnixMilli(), 10)
		sign := dingTalkSign(timestamp, secret)
		parsed, err := url.Parse(webhook)
		if err != nil {
			return renderedRequest{}, err
		}
		query := parsed.Query()
		query.Set("timestamp", timestamp)
		query.Set("sign", sign)
		parsed.RawQuery = query.Encode()
		webhook = parsed.String()
	}
	return marshalRequest(webhook, body)
}

func (dingTalkRenderer) ValidateResponse(response networkResponse) error {
	if err := validateHTTP(ChannelDingTalk, response); err != nil {
		return err
	}
	code, message, err := responseStatus(response.Body, "errcode", "", "errmsg", "")
	if err != nil {
		return fmt.Errorf("notice: parse dingtalk response: %w", err)
	}
	if code != "0" {
		return &PlatformError{Channel: ChannelDingTalk, Code: code, Message: message}
	}
	return nil
}

func dingTalkSign(timestamp, secret string) string {
	digest := hmac.New(sha256.New, []byte(secret))
	_, _ = digest.Write([]byte(timestamp + "\n" + secret))
	return base64.StdEncoding.EncodeToString(digest.Sum(nil))
}

func dingTalkMarkdown(title, content string) map[string]any {
	return map[string]any{"msgtype": "markdown", "markdown": map[string]any{"title": title, "text": content}}
}

func dingTalkColorMarkdown(segments []TextSegment) string {
	var builder strings.Builder
	for _, segment := range segments {
		prefix := map[Color]string{
			ColorInfo: "【提示】", ColorSuccess: "【成功】", ColorWarning: "【警告】", ColorDanger: "【异常】",
		}[segment.Color]
		content := escapeText(segment.Text)
		if prefix != "" {
			content = prefix + content
		}
		if segment.Bold || segment.Color == ColorWarning || segment.Color == ColorDanger {
			content = "**" + content + "**"
		}
		builder.WriteString(content)
	}
	return builder.String()
}