package richtext

import (
	"fmt"
	"regexp"
	"strings"
)

func RemoveRichText(text string) string {
	// Regular expression to replace <br/> and <p> tags with newline
	reBr := regexp.MustCompile(`<(br|p)(\s[^>]*)?>`)
	text = reBr.ReplaceAllString(text, "\n")

	// Add four full-width spaces after each newline
	reNewline := regexp.MustCompile(`\n`)
	text = reNewline.ReplaceAllString(text, "\n　　") // 两个全角空格等于四个半角空格，即四个汉字的距离

	// Regular expression to replace &nbsp; with empty string
	reNbsp := regexp.MustCompile(`&nbsp;`)
	text = reNbsp.ReplaceAllString(text, "")

	// Regular expression to match other HTML tags
	re := regexp.MustCompile("<[^>]*>")
	plainText := re.ReplaceAllString(text, "")

	plainText = strings.TrimSpace(plainText)
	// plainText = "　　" + plainText

	return plainText
}

func ExtractImageURLs(text string) []string {
	re := regexp.MustCompile(`<img[^>]+\bsrc=["']([^"']+)["']`)
	matches := re.FindAllStringSubmatch(text, -1)

	var urls []string
	for _, match := range matches {
		urls = append(urls, match[1])
	}

	return urls
}

func ConvertToRichText(plainText string, imageURLs []string) string {
	// 将纯文本分割成段落
	paragraphs := strings.Split(plainText, "\n")

	// 创建一个StringBuilder来构建富文本
	var richText strings.Builder

	// 将每个段落包装在<p>标签中
	for _, paragraph := range paragraphs {
		richText.WriteString("<p>")
		richText.WriteString(paragraph)
		richText.WriteString("</p>")
	}

	// 将每个图片URL包装在<img>标签中，并附加到富文本中
	for _, imageURL := range imageURLs {
		richText.WriteString("<img src=\"")
		richText.WriteString(imageURL)
		richText.WriteString("\" />")
	}

	// 返回富文本字符串
	return richText.String()
}

// 传入一个字符串数组，将其包装为一个富文本图片标签
func ConvertImageURLsToRichText(imageURLs []string) string {
	var richText strings.Builder
	for _, imageURL := range imageURLs {
		richText.WriteString(fmt.Sprintf(`<p><img src="%s" /></p>`, imageURL))
	}

	return richText.String()
}