package building

import (
	"fmt"
	"os"
	"path"

	"github.com/gochan-org/gochan/pkg/config"
	"github.com/gochan-org/gochan/pkg/gcsql"
	"github.com/gochan-org/gochan/pkg/gctemplates"
	"github.com/gochan-org/gochan/pkg/gcutil"
	"github.com/gochan-org/gochan/pkg/server/serverutil"
)

type catalogThreadData struct {
	*Post
	Replies       int     `json:"replies"`
	Images        int     `json:"images"`
	OmittedPosts  int     `json:"omitted_posts"`  // posts in the thread but not shown on the board page
	OmittedImages int     `json:"omitted_images"` // uploads in the thread but not shown on the board page
	Stickied      int     `json:"sticky"`
	Locked        int     `json:"closed"`
	Posts         []*Post `json:"-"`
	uploads       []gcsql.Upload
}

type catalogPage struct {
	PageNum int                 `json:"page"`
	Threads []catalogThreadData `json:"threads"`
}

type boardCatalog struct {
	pages       []catalogPage // this array gets marshalled, not the boardCatalog object
	numPages    int
	currentPage int
}

// fillPages fills the catalog's pages array with pages of the specified size, with the remainder
// on the last page
func (catalog *boardCatalog) fillPages(threadsPerPage int, threads []catalogThreadData) {
	catalog.pages = []catalogPage{} // clear the array if it isn't already
	catalog.numPages = len(threads) / threadsPerPage
	remainder := len(threads) % threadsPerPage
	currentThreadIndex := 0
	var i int
	for i = 0; i < catalog.numPages; i++ {
		catalog.pages = append(catalog.pages,
			catalogPage{
				PageNum: i + 1,
				Threads: threads[currentThreadIndex : currentThreadIndex+threadsPerPage],
			},
		)
		currentThreadIndex += threadsPerPage
	}
	if remainder > 0 {
		catalog.pages = append(catalog.pages,
			catalogPage{
				PageNum: i + 1,
				Threads: threads[len(threads)-remainder:],
			},
		)
	}
}

func getBoardTopPosts(board string) ([]*Post, error) {
	const query = `SELECT id, thread_id, ip, name, tripcode, email, subject, created_on, last_modified, parent_id,
		last_bump, message, message_raw, board_id, dir, original_filename, filename, checksum, filesize, tw, th,
		width, height, locked, stickied, cyclical, flag, country, is_deleted
		FROM DBPREFIXv_building_posts WHERE id = parent_id AND dir = ?`
	var posts []*Post

	err := QueryPosts(query, []any{board}, func(p *Post) error {
		posts = append(posts, p)
		return nil
	})
	return posts, err
}

// BuildCatalog builds the catalog for a board with a given id
func BuildCatalog(boardID int) error {
	errEv := gcutil.LogError(nil).
		Str("building", "catalog").
		Int("boardID", boardID)
	err := gctemplates.InitTemplates(gctemplates.Catalog)
	if err != nil {
		errEv.Err(err).Send()
		return err
	}

	board, err := gcsql.GetBoardFromID(boardID)
	if err != nil {
		errEv.Err(err).Caller().Msg("Unable to get board information")
		return err
	}
	errEv.Str("boardDir", board.Dir)
	criticalCfg := config.GetSystemCriticalConfig()
	catalogPath := path.Join(criticalCfg.DocumentRoot, board.Dir, "catalog.html")
	catalogFile, err := os.OpenFile(catalogPath, os.O_CREATE|os.O_RDWR|os.O_TRUNC, config.NormalFileMode)
	if err != nil {
		errEv.Err(err).Caller().Send()
		return fmt.Errorf("failed opening /%s/catalog.html: %w", board.Dir, err)
	}

	if err = config.TakeOwnershipOfFile(catalogFile); err != nil {
		errEv.Err(err).Caller().Send()
		return fmt.Errorf("failed taking ownership of /%s/catalog.html", board.Dir)
	}

	threadOPs, err := getBoardTopPosts(board.Dir)
	if err != nil {
		errEv.Err(err).Caller().Send()
		return fmt.Errorf("failed building catalog for /%s/", board.Dir)
	}
	boardConfig := config.GetBoardConfig(board.Dir)

	if err = serverutil.MinifyTemplate(gctemplates.Catalog, map[string]any{
		"boards":      gcsql.AllBoards,
		"board":       board,
		"boardConfig": boardConfig,
		"sections":    gcsql.AllSections,
		"threads":     threadOPs,
	}, catalogFile, "text/html"); err != nil {
		errEv.Err(err).Caller().Send()
		return fmt.Errorf("failed building catalog for /%s/", board.Dir)
	}
	return catalogFile.Close()
}