package cmd

import (
	"fmt"
	"strings"

	"github.com/runescape-wiki/rsw/internal/extract"
	"github.com/runescape-wiki/rsw/internal/render"
	"github.com/runescape-wiki/rsw/internal/wiki"
	"github.com/spf13/cobra"
)

func newPageCmd() *cobra.Command {
	var pageSection string

	cmd := &cobra.Command{
		Use:   "page <title>",
		Short: "Fetch and display a wiki page",
		Long: `Fetches a wiki page and renders it as markdown. Optionally filter
to a specific section.

Examples:
  rsw osrs page "Dragon scimitar"
  rsw rs3 page "Mining" --section "Training"`,
		Args: cobra.MinimumNArgs(1),
		RunE: func(cmd *cobra.Command, args []string) error {
			title := args[0]
			client := wiki.NewClient(GameBaseURL())

			page, err := client.GetPage(title)
			if err != nil {
				return fmt.Errorf("failed to fetch page: %w", err)
			}

			wikitext := page.Wikitext

			if pageSection != "" {
				idx := wiki.FindSectionIndex(page.Sections, pageSection)
				if idx == -1 {
					needle := strings.ToLower(pageSection)
					// Case-insensitive exact match
					for _, s := range page.Sections {
						if strings.ToLower(s.Line) == needle {
							fmt.Sscanf(s.Index, "%d", &idx)
							break
						}
					}
					// Case-insensitive prefix match (e.g. "Location" → "Locations")
					if idx == -1 {
						for _, s := range page.Sections {
							if strings.HasPrefix(strings.ToLower(s.Line), needle) {
								fmt.Sscanf(s.Index, "%d", &idx)
								break
							}
						}
					}
					// Case-insensitive contains match
					if idx == -1 {
						for _, s := range page.Sections {
							if strings.Contains(strings.ToLower(s.Line), needle) {
								fmt.Sscanf(s.Index, "%d", &idx)
								break
							}
						}
					}
				}
				if idx == -1 {
					return fmt.Errorf("section %q not found. Available sections: %s",
						pageSection, listSections(page.Sections))
				}
				sectionPage, err := client.GetPageSection(title, idx)
				if err != nil {
					return fmt.Errorf("failed to fetch section: %w", err)
				}
				wikitext = sectionPage.Wikitext
			}

			if Raw() {
				fmt.Println(wikitext)
				return nil
			}

			md := render.New()
			md.H1(page.Title)

			if pageSection == "" && len(page.Sections) > 0 {
				md.H2("Sections")
				for _, s := range page.Sections {
					indent := ""
					if s.Level == "3" {
						indent = "  "
					} else if s.Level == "4" {
						indent = "    "
					}
					md.Line(fmt.Sprintf("%s- %s", indent, s.Line))
				}
				md.Newline()
				md.HR()
			}

			plain := extract.ExtractPlainText(wikitext)
			md.P(plain)

			fmt.Print(md.String())
			return nil
		},
	}

	cmd.Flags().StringVar(&pageSection, "section", "", "Fetch only the named section")
	return cmd
}

func listSections(sections []wiki.Section) string {
	names := make([]string, len(sections))
	for i, s := range sections {
		names[i] = s.Line
	}
	return strings.Join(names, ", ")
}

func init() {
	RegisterCommand(newPageCmd)
}