package cmd

import (
	"context"
	"encoding/json"
	"fmt"
	"net/url"
	"os"
	"path/filepath"
	"strings"
	"time"

	"github.com/spf13/cobra"
	"github.com/yourorg/devour/internal/markdown"
	"github.com/yourorg/devour/internal/scraper"
)

var scrapeCmd = &cobra.Command{
	Use:   "scrape <source>",
	Short: "Scrape documentation from a source",
	Long: `Scrape and index documentation from various sources.

Supported source types:
  - godocs: Go packages (pkg.go.dev)
  - rustdocs: Rust crates (docs.rs)
  - pythondocs: Python modules (docs.python.org)
  - javadocs: Java packages (docs.oracle.com)
  - springdocs: Spring Boot (docs.spring.io)
  - tsdocs: TypeScript (typescriptlang.org)
  - reactdocs: React (react.dev)
  - vuedocs: Vue.js (vuejs.org)
  - nuxtdocs: Nuxt (nuxt.com)
  - mcpdocs: MCP servers (hub.docker.com/mcp)
  - dockerdocs: Docker (docs.docker.com)
  - cloudflaredocs: Cloudflare (developers.cloudflare.com)
  - astrodocs: Astro (docs.astro.build)
  - url: Generic web pages
  - github: GitHub repositories

Examples:
  devour scrape https://pkg.go.dev/net/http --type godocs
  devour scrape https://react.dev/reference/react --type reactdocs
  devour scrape https://developers.cloudflare.com/ --type cloudflaredocs
  devour scrape --sources sources.yaml`,
	Args: cobra.MaximumNArgs(1),
	RunE: runScrape,
}

var (
	scrapeFormat      string
	scrapeSources     string
	scrapeOutput      string
	scrapeConcurrency int
	scrapeType        string
)

func init() {
	scrapeCmd.Flags().StringVarP(&scrapeFormat, "format", "f", "json", "output format (json, markdown)")
	scrapeCmd.Flags().StringVarP(&scrapeSources, "sources", "s", "", "YAML file with source definitions")
	scrapeCmd.Flags().StringVarP(&scrapeOutput, "output", "o", "", "output directory (default: devour_data/docs)")
	scrapeCmd.Flags().IntVar(&scrapeConcurrency, "concurrency", 10, "parallel scraping workers")
	scrapeCmd.Flags().StringVarP(&scrapeType, "type", "t", "", "source type (auto-detected if not specified)")
}

func runScrape(cmd *cobra.Command, args []string) error {
	if scrapeSources != "" {
		return scrapeFromConfig(scrapeSources)
	}

	if len(args) == 0 {
		return fmt.Errorf("source argument required when not using --sources flag")
	}

	sourceURL := args[0]

	config := &scraper.Config{
		UserAgent:   "Devour/1.0 (Documentation Scraper)",
		Timeout:     30 * time.Second,
		RetryCount:  3,
		RetryDelay:  1 * time.Second,
		Concurrency: scrapeConcurrency,
	}

	sourceType := scraper.SourceType(scrapeType)
	if sourceType == "" {
		sourceType = detectSourceType(sourceURL)
	}

	fmt.Printf("Scraping: %s\n", sourceURL)
	fmt.Printf("  Type: %s\n", sourceType)
	fmt.Printf("  Concurrency: %d\n", scrapeConcurrency)
	fmt.Println()

	s := scraper.NewScraper(sourceType, config)
	if s == nil {
		return fmt.Errorf("unsupported source type: %s", sourceType)
	}

	source := &scraper.Source{
		Name: extractName(sourceURL),
		Type: sourceType,
		URL:  sourceURL,
	}

	ctx, cancel := context.WithTimeout(context.Background(), 60*time.Second)
	defer cancel()

	docs, err := s.Scrape(ctx, source)
	if err != nil {
		return fmt.Errorf("scraping failed: %w", err)
	}

	fmt.Printf("✓ Scraped %d documents\n\n", len(docs))

	if scrapeOutput == "" {
		scrapeOutput = "devour_data/docs"
	}

	if err := os.MkdirAll(scrapeOutput, 0755); err != nil {
		return fmt.Errorf("failed to create output directory: %w", err)
	}

	for i, doc := range docs {
		var filename string
		var content []byte

		if scrapeFormat == "markdown" {
			filename = fmt.Sprintf("%s_%d.md", sanitizeFilename(doc.Title), i)

			// Create enhanced markdown document
			markdownDoc := &markdown.Document{
				ID:        doc.ID,
				Source:    doc.Source,
				Type:      string(doc.Type),
				Title:     doc.Title,
				Content:   doc.Content,
				URL:       doc.URL,
				Metadata:  doc.Metadata,
				Hash:      doc.Hash,
				Timestamp: doc.Timestamp,
			}

			formatter := markdown.NewFormatter()
			content = []byte(formatter.FormatWithTOC(markdownDoc))
		} else {
			filename = fmt.Sprintf("%s_%d.json", sanitizeFilename(doc.Title), i)
			content, err = json.MarshalIndent(doc, "", "  ")
			if err != nil {
				return fmt.Errorf("failed to marshal document: %w", err)
			}
		}

		filePath := filepath.Join(scrapeOutput, filename)
		if err := os.WriteFile(filePath, content, 0644); err != nil {
			return fmt.Errorf("failed to write document: %w", err)
		}

		fmt.Printf("  📄 %s (%s)\n", filename, doc.Type)
	}

	fmt.Printf("\n✓ Scraping complete!\n")
	fmt.Printf("   Output: %s\n", scrapeOutput)
	fmt.Println("   Run 'devour status' to see indexed documents")

	return nil
}

func scrapeFromConfig(configPath string) error {
	return fmt.Errorf("scraping from config file not yet implemented")
}

func detectSourceType(sourceURL string) scraper.SourceType {
	u, err := url.Parse(sourceURL)
	if err != nil {
		return scraper.SourceTypeWeb
	}

	host := u.Host
	path := u.Path

	switch {
	case host == "pkg.go.dev" || strings.HasSuffix(host, "pkg.go.dev"):
		return scraper.SourceTypeGoDocs
	case host == "docs.rs" || host == "doc.rust-lang.org":
		return scraper.SourceTypeRustDocs
	case host == "docs.python.org":
		return scraper.SourceTypePythonDocs
	case host == "docs.oracle.com":
		return scraper.SourceTypeJavaDocs
	case host == "docs.spring.io":
		return scraper.SourceTypeSpringDocs
	case host == "www.typescriptlang.org" || host == "typescriptlang.org":
		return scraper.SourceTypeTSDocs
	case host == "react.dev":
		return scraper.SourceTypeReactDocs
	case host == "vuejs.org":
		return scraper.SourceTypeVueDocs
	case host == "nuxt.com":
		return scraper.SourceTypeNuxtDocs
	case strings.Contains(host, "docker.com") || host == "docs.docker.com":
		if strings.Contains(path, "/mcp/") {
			return scraper.SourceTypeMCPDocs
		}
		return scraper.SourceTypeDockerDocs
	case host == "developers.cloudflare.com":
		return scraper.SourceTypeCloudflareDocs
	case host == "docs.astro.build":
		return scraper.SourceTypeAstroDocs
	case host == "github.com":
		return scraper.SourceTypeGitHub
	default:
		return scraper.SourceTypeWeb
	}
}

func extractName(sourceURL string) string {
	u, err := url.Parse(sourceURL)
	if err != nil {
		return "unknown"
	}

	parts := strings.Split(strings.Trim(u.Path, "/"), "/")
	if len(parts) > 0 {
		return parts[len(parts)-1]
	}

	return u.Host
}

func sanitizeFilename(name string) string {
	name = strings.ToLower(name)
	name = strings.ReplaceAll(name, " ", "_")
	name = strings.ReplaceAll(name, "/", "_")
	name = strings.ReplaceAll(name, ":", "_")
	name = strings.ReplaceAll(name, ".", "_")

	if len(name) > 50 {
		name = name[:50]
	}

	return name
}