import sqlite3
import csv

class AnimeBackend:
    def __init__(self):
        self.db = sqlite3.connect('anime_backlog.db')
        self.create_table()

    def create_table(self):
        cursor = self.db.cursor()
        cursor.execute("""
            CREATE TABLE IF NOT EXISTS anime (
                id INTEGER PRIMARY KEY AUTOINCREMENT,
                name TEXT NOT NULL,
                year INTEGER NOT NULL,
                season TEXT,
                status TEXT NOT NULL DEFAULT 'unwatched',
                type TEXT,
                comment TEXT,
                url TEXT
            )
        """)
        self.db.commit()

    def get_pre_2010_entries(self):
        cursor = self.db.cursor()
        cursor.execute("SELECT * FROM anime WHERE year < 2010 ORDER BY year DESC, name")
        return cursor.fetchall()

    def get_years(self):
        cursor = self.db.cursor()
        cursor.execute("SELECT DISTINCT year FROM anime WHERE year >= 2010 ORDER BY year DESC")
        return [row[0] for row in cursor.fetchall()]

    def get_entries_for_season(self, year, season):
        cursor = self.db.cursor()
        cursor.execute("SELECT * FROM anime WHERE year = ? AND season = ? ORDER BY name", (year, season))
        return cursor.fetchall()

    def get_anime_by_id(self, anime_id):
        cursor = self.db.cursor()
        cursor.execute("SELECT * FROM anime WHERE id = ?", (anime_id,))
        return cursor.fetchone()

    def add_anime(self, data):
        cursor = self.db.cursor()
        cursor.execute(
            "INSERT INTO anime (name, year, season, status, type, comment, url) VALUES (?, ?, ?, ?, ?, ?, ?)",
            (data['name'], data['year'], data['season'], data['status'], data['type'], data['comment'], data['url'])
        )
        self.db.commit()

    def edit_anime(self, anime_id, data):
        cursor = self.db.cursor()
        cursor.execute(
            "UPDATE anime SET name=?, year=?, season=?, status=?, type=?, comment=?, url=? WHERE id=?",
            (data['name'], data['year'], data['season'], data['status'], data['type'], data['comment'], data['url'], anime_id)
        )
        self.db.commit()

    def delete_anime(self, anime_id):
        cursor = self.db.cursor()
        cursor.execute("DELETE FROM anime WHERE id = ?", (anime_id,))
        self.db.commit()

    def change_status(self, anime_id, new_status):
        cursor = self.db.cursor()
        cursor.execute("UPDATE anime SET status = ? WHERE id = ?", (new_status, anime_id))
        self.db.commit()

    def add_placeholders_for_year(self, year):
        cursor = self.db.cursor()
        for season in ['winter', 'spring', 'summer', 'fall', '']:
            cursor.execute(
                "INSERT INTO anime (name, year, season, status, type, comment, url) VALUES (?, ?, ?, ?, ?, ?, ?)",
                ('Placeholder', year, season, 'unwatched', '', 'Delete or edit me', '')
            )
        self.db.commit()

    def import_from_csv(self, file_name):
        with open(file_name, 'r', newline='') as f:
            reader = csv.reader(f)
            header = next(reader, None)
            if header:
                cursor = self.db.cursor()
                for row in reader:
                    if len(row) == 7:
                        name, year_str, season, status, type_, comment, url = row
                    elif len(row) == 8:
                        _, name, year_str, season, status, type_, comment, url = row
                    else:
                        continue
                    try:
                        year = int(year_str)
                    except ValueError:
                        continue
                    cursor.execute(
                        "SELECT id FROM anime WHERE name = ? AND year = ? AND season = ?",
                        (name, year, season)
                    )
                    if not cursor.fetchone():
                        cursor.execute(
                            "INSERT INTO anime (name, year, season, status, type, comment, url) VALUES (?, ?, ?, ?, ?, ?, ?)",
                            (name, year, season, status, type_, comment, url)
                        )
                self.db.commit()

    def export_to_csv(self, file_name):
        cursor = self.db.cursor()
        cursor.execute("SELECT * FROM anime")
        rows = cursor.fetchall()
        with open(file_name, 'w', newline='') as f:
            writer = csv.writer(f)
            writer.writerow(['id', 'name', 'year', 'season', 'status', 'type', 'comment', 'url'])
            writer.writerows(rows)