package mark

import (
	"fmt"
	"strings"

	"github.com/kovetskiy/mark/pkg/confluence"
	"github.com/reconquest/karma-go"
)

func EnsureAncestry(
	api *confluence.API,
	space string,
	ancestry []string,
) (*confluence.PageInfo, error) {
	var parent *confluence.PageInfo

	rest := ancestry

	for i, title := range ancestry {
		page, err := api.FindPage(space, title)
		if err != nil {
			return nil, karma.Format(
				err,
				`error during finding parent page with title '%s': %s`,
				title,
			)
		}

		if page == nil {
			break
		}

		logger.Tracef("parent page '%s' exists: %s", title, page.Links.Full)

		rest = ancestry[i:]
		parent = page
	}

	if parent != nil {
		rest = rest[1:]
	} else {
		page, err := api.FindRootPage(space)
		if err != nil {
			return nil, karma.Format(
				err,
				"can't find root page for space '%s': %s", space,
			)
		}

		parent = page
	}

	if len(rest) == 0 {
		return parent, nil
	}

	logger.Debugf(
		"empty pages under '%s' to be created: %s",
		parent.Title,
		strings.Join(rest, ` > `),
	)

	for _, title := range rest {
		page, err := api.CreatePage(space, parent, title, ``)
		if err != nil {
			return nil, karma.Format(
				err,
				`error during creating parent page with title '%s': %s`,
				title,
			)
		}

		parent = page
	}

	return parent, nil
}

func ValidateAncestry(
	api *confluence.API,
	space string,
	ancestry []string,
) (*confluence.PageInfo, error) {
	page, err := api.FindPage(space, ancestry[len(ancestry)-1])
	if err != nil {
		return nil, err
	}

	if page == nil {
		return nil, nil
	}

	if len(page.Ancestors) < 1 {
		return nil, fmt.Errorf(`page '%s' has no parents`, page.Title)
	}

	if len(page.Ancestors) < len(ancestry) {
		return nil, fmt.Errorf(
			"page '%s' has fewer parents than specified: %s",
			page.Title,
			strings.Join(ancestry, ` > `),
		)
	}

	// skipping root article title
	for i, ancestor := range page.Ancestors[1:len(ancestry)] {
		if ancestor.Title != ancestry[i] {
			return nil, fmt.Errorf(
				"broken ancestry tree; expected tree: %s; "+
					"encountered '%s' at position of '%s'",
				strings.Join(ancestry, ` > `),
				ancestor.Title,
				ancestry[i],
			)
		}
	}

	return page, nil
}