package repository

import (
	"database/sql"
	"encoding/json"
	"fmt"

	"floorvisualizer/internal/model"
)

func InsertArticles(d *sql.DB, articles []model.Article) error {
	for i := range articles {
		articles[i].SetImageJSON()
	}
	const batchSize = 50
	for start := 0; start < len(articles); start += batchSize {
		end := start + batchSize
		if end > len(articles) {
			end = len(articles)
		}
		batch := articles[start:end]
		for _, a := range batch {
			_, err := d.Exec(`
				INSERT INTO articles (title, summary, content, cover_url, image_urls)
				VALUES ($1,$2,$3,$4,$5)
			`, a.Title, a.Summary, a.Content, a.CoverURL, a.ImageJSON)
			if err != nil {
				return fmt.Errorf("insert article: %w", err)
			}
		}
	}
	return nil
}

func GetArticleByID(d *sql.DB, id int) (*model.Article, error) {
	var a model.Article
	var imageJSON string
	err := d.QueryRow(`
		SELECT id, title, summary, content, cover_url, image_urls::text, created_at
		FROM articles WHERE id = $1
	`, id).Scan(&a.ID, &a.Title, &a.Summary, &a.Content, &a.CoverURL, &imageJSON, &a.CreatedAt)
	if err != nil {
		return nil, err
	}
	json.Unmarshal([]byte(imageJSON), &a.ImageURLs)
	if a.ImageURLs == nil {
		a.ImageURLs = []string{}
	}
	return &a, nil
}

func ListArticles(d *sql.DB, page, limit int) ([]model.Article, int, error) {
	if limit <= 0 {
		limit = 10
	}
	if page <= 0 {
		page = 1
	}
	var total int
	if err := d.QueryRow("SELECT COUNT(*) FROM articles").Scan(&total); err != nil {
		return nil, 0, err
	}

	offset := (page - 1) * limit
	rows, err := d.Query(`
		SELECT id, title, summary, content, cover_url, image_urls::text, created_at
		FROM articles ORDER BY id LIMIT $1 OFFSET $2
	`, limit, offset)
	if err != nil {
		return nil, 0, err
	}
	defer rows.Close()

	var out []model.Article
	for rows.Next() {
		var a model.Article
		var imageJSON string
		if err := rows.Scan(&a.ID, &a.Title, &a.Summary, &a.Content, &a.CoverURL, &imageJSON, &a.CreatedAt); err != nil {
			return nil, 0, err
		}
		json.Unmarshal([]byte(imageJSON), &a.ImageURLs)
		if a.ImageURLs == nil {
			a.ImageURLs = []string{}
		}
		out = append(out, a)
	}
	return out, total, rows.Err()
}

func RandomArticles(d *sql.DB, count int) ([]model.Article, error) {
	rows, err := d.Query(`
		SELECT id, title, summary, content, cover_url, image_urls::text, created_at
		FROM articles ORDER BY RANDOM() LIMIT $1
	`, count)
	if err != nil {
		return nil, err
	}
	defer rows.Close()

	var out []model.Article
	for rows.Next() {
		var a model.Article
		var imageJSON string
		if err := rows.Scan(&a.ID, &a.Title, &a.Summary, &a.Content, &a.CoverURL, &imageJSON, &a.CreatedAt); err != nil {
			return nil, err
		}
		json.Unmarshal([]byte(imageJSON), &a.ImageURLs)
		if a.ImageURLs == nil {
			a.ImageURLs = []string{}
		}
		out = append(out, a)
	}
	return out, rows.Err()
}