package cmd

import (
	"fmt"
	"os"
	"strings"

	"github.com/alecthomas/chroma/v2/formatters"
	"github.com/alecthomas/chroma/v2/lexers"
	"github.com/alecthomas/chroma/v2/styles"
	"github.com/zemenawi/zutils/pkg/colors"
	"github.com/zemenawi/zutils/pkg/formatter"
)

func init() {
	formatter.ReadHandlers.Register(".md", MarkdownHandler)
	formatter.ReadHandlers.Register(".markdown", MarkdownHandler)
}

func MarkdownHandler(args []string) error {
	if len(args) < 1 {
		return fmt.Errorf("please specify a markdown file path")
	}

	filePath := args[0]

	file, err := os.Open(filePath)
	if err != nil {
		return fmt.Errorf("error opening file: %w", err)
	}
	defer file.Close()

	fileInfo, err := file.Stat()
	if err != nil {
		return fmt.Errorf("error getting file info: %w", err)
	}

	if fileInfo.IsDir() {
		return fmt.Errorf("'%s' is a directory, not a readable file", filePath)
	}

	content := formatter.ReadFileContent(file)

	fmt.Printf("%s%s╔══════════════════════════════════════╗%s\n", colors.Cyan, colors.Bold, colors.Reset)
	fmt.Printf("%s%s║%s %-38s %s%s║%s\n", colors.Cyan, colors.Bold, colors.Reset, filePath, colors.Cyan, colors.Bold, colors.Reset)
	fmt.Printf("%s%s╚══════════════════════════════════════╝%s\n", colors.Cyan, colors.Bold, colors.Reset)
	fmt.Println()

	lines := strings.Split(content, "\n")
	inCodeBlock := false
	codeBuffer := &strings.Builder{}
	codeLang := ""

	for _, line := range lines {
		if strings.HasPrefix(line, "```") {
			if !inCodeBlock {
				inCodeBlock = true
				codeLang = strings.TrimPrefix(line, "```")
				codeBuffer.Reset()
			} else {
				inCodeBlock = false
				renderCodeBlock(codeBuffer.String(), codeLang)
				codeBuffer.Reset()
				codeLang = ""
			}
			continue
		}

		if inCodeBlock {
			if codeBuffer.Len() > 0 {
				codeBuffer.WriteString("\n")
			}
			codeBuffer.WriteString(line)
			continue
		}

		if strings.HasPrefix(line, "# ") {
			fmt.Printf("%s%s%s%s\n", colors.Bold, colors.Yellow, line[2:], colors.Reset)
		} else if strings.HasPrefix(line, "## ") {
			fmt.Printf("%s%s%s%s\n", colors.Bold, colors.Green, line[3:], colors.Reset)
		} else if strings.HasPrefix(line, "### ") {
			fmt.Printf("%s%s%s%s\n", colors.Bold, colors.Cyan, line[4:], colors.Reset)
		} else if strings.HasPrefix(line, "- [ ]") {
			fmt.Printf("  %s☐%s %s\n", colors.Gray, colors.Reset, line[5:])
		} else if strings.HasPrefix(line, "- [x]") {
			fmt.Printf("  %s☑%s %s\n", colors.Green, colors.Reset, line[5:])
		} else if strings.HasPrefix(line, "- ") && !strings.HasPrefix(line, "- [") {
			fmt.Printf("  %s•%s %s\n", colors.Blue, colors.Reset, line[2:])
		} else if strings.HasPrefix(line, "> ") {
			fmt.Printf("%s%s%s%s\n", colors.Gray, colors.Italic, line[2:], colors.Reset)
		} else if strings.TrimSpace(line) != "" {
			fmt.Printf("%s\n", line)
		} else {
			fmt.Println()
		}
	}

	return nil
}

func renderCodeBlock(code, lang string) {
	if code == "" {
		return
	}

	fmt.Printf("%s%s╔═══ %s ═══╗%s\n", colors.Gray, colors.Dim, lang, colors.Reset)

	lexer := lexers.Match(lang)
	if lexer == nil {
		lexer = lexers.Fallback
	}

	iterator, _ := lexer.Tokenise(nil, code)
	formatter_ := formatters.TTY256
	style := styles.Get("monokai")
	if style == nil {
		style = styles.Fallback
	}

	var buf strings.Builder
	formatter_.Format(&buf, style, iterator)

	output := buf.String()
	for _, line := range strings.Split(output, "\n") {
		if line != "" {
			fmt.Printf("%s%s│ %s%s\n", colors.Gray, colors.Dim, colors.Reset, line)
		}
	}
	fmt.Printf("%s%s╚══════════════╝%s\n", colors.Gray, colors.Dim, colors.Reset)
	fmt.Println()
}