import { DatabaseSync, type SQLOutputValue } from "node:sqlite";
import {
  type Comment,
  Dump,
  type Playlist,
  type RichContent,
  type User,
} from "./interfaces.ts";

export const db = new DatabaseSync("api/sql/gerbeur.db");
db.exec("PRAGMA foreign_keys = ON;");

// Migration: add is_private column if it doesn't exist yet
try {
  db.exec(`ALTER TABLE dumps ADD COLUMN is_private INTEGER NOT NULL DEFAULT 0;`);
} catch { /* column already exists */ }

// Migration: create comments table if it doesn't exist yet
try {
  db.exec(`CREATE TABLE IF NOT EXISTS comments (
    id TEXT PRIMARY KEY,
    dump_id TEXT NOT NULL REFERENCES dumps(id) ON DELETE CASCADE,
    user_id TEXT NOT NULL REFERENCES users(id) ON DELETE CASCADE,
    parent_id TEXT REFERENCES comments(id) ON DELETE CASCADE,
    body TEXT NOT NULL,
    created_at TEXT NOT NULL,
    deleted INTEGER NOT NULL DEFAULT 0
  );`);
  db.exec(`CREATE INDEX IF NOT EXISTS idx_comments_dump ON comments(dump_id, created_at);`);
  db.exec(`CREATE INDEX IF NOT EXISTS idx_votes_user ON votes(user_id);`);
  db.exec(`CREATE INDEX IF NOT EXISTS idx_playlist_dumps_dump ON playlist_dumps(dump_id);`);
} catch { /* already exists */ }

// Migration: add deleted column to comments if it doesn't exist yet
try {
  db.exec(`ALTER TABLE comments ADD COLUMN deleted INTEGER NOT NULL DEFAULT 0;`);
} catch { /* column already exists */ }

/**
 * Database Row Types
 */

export interface DumpRow {
  id: string;
  kind: string;
  title: string;
  comment: string | null;
  user_id: string;
  created_at: string;
  url: string | null;
  rich_content: string | null;
  file_name: string | null;
  file_mime: string | null;
  file_size: number | null;
  vote_count: number;
  comment_count?: number;
  is_private: number;
  [key: string]: SQLOutputValue; // Index signature
}

export interface UserRow {
  id: string;
  username: string;
  password_hash: string;
  is_admin: number;
  created_at: string;
  avatar_mime: string | null;
  [key: string]: SQLOutputValue; // Index signature
}

/**
 * Type Guards
 */

export function isDumpRow(obj: Record<string, SQLOutputValue>): obj is DumpRow {
  return !!obj &&
    typeof obj === "object" &&
    "id" in obj && typeof obj.id === "string" &&
    "kind" in obj && typeof obj.kind === "string" &&
    "title" in obj && typeof obj.title === "string" &&
    "comment" in obj &&
    (typeof obj.comment === "string" || obj.comment === null) &&
    "user_id" in obj && typeof obj.user_id === "string" &&
    "created_at" in obj && typeof obj.created_at === "string" &&
    "url" in obj && (typeof obj.url === "string" || obj.url === null) &&
    "rich_content" in obj &&
    (typeof obj.rich_content === "string" || obj.rich_content === null) &&
    "file_name" in obj &&
    (typeof obj.file_name === "string" || obj.file_name === null) &&
    "file_mime" in obj &&
    (typeof obj.file_mime === "string" || obj.file_mime === null) &&
    "file_size" in obj &&
    (typeof obj.file_size === "number" || obj.file_size === null) &&
    "vote_count" in obj && typeof obj.vote_count === "number" &&
    "is_private" in obj && typeof obj.is_private === "number";
}

export function isUserRow(obj: Record<string, SQLOutputValue>): obj is UserRow {
  return !!obj &&
    typeof obj === "object" &&
    "id" in obj && typeof obj.id === "string" &&
    "username" in obj && typeof obj.username === "string" &&
    "password_hash" in obj && typeof obj.password_hash === "string" &&
    "is_admin" in obj && typeof obj.is_admin === "number" &&
    "created_at" in obj && typeof obj.created_at === "string" &&
    "avatar_mime" in obj &&
    (typeof obj.avatar_mime === "string" || obj.avatar_mime === null);
}

/**
 * Conversion Helpers
 */

export function dumpRowToApi(row: DumpRow): Dump {
  return {
    id: row.id,
    kind: row.kind as "url" | "file",
    title: row.title,
    comment: row.comment ?? undefined,
    userId: row.user_id,
    createdAt: new Date(row.created_at),
    url: row.url ?? undefined,
    richContent: row.rich_content
      ? (JSON.parse(row.rich_content) as RichContent)
      : undefined,
    fileName: row.file_name ?? undefined,
    fileMime: row.file_mime ?? undefined,
    fileSize: row.file_size ?? undefined,
    voteCount: row.vote_count,
    commentCount: row.comment_count ?? 0,
    isPrivate: Boolean(row.is_private),
  };
}

export function dumpApiToRow(dump: Dump): DumpRow {
  return {
    id: dump.id,
    kind: dump.kind,
    title: dump.title,
    comment: dump.comment ?? null,
    user_id: dump.userId,
    created_at: dump.createdAt.toISOString(),
    url: dump.url ?? null,
    rich_content: dump.richContent ? JSON.stringify(dump.richContent) : null,
    file_name: dump.fileName ?? null,
    file_mime: dump.fileMime ?? null,
    file_size: dump.fileSize ?? null,
    vote_count: dump.voteCount,
    is_private: dump.isPrivate ? 1 : 0,
  };
}

export function userRowToApi(row: UserRow): User {
  return {
    id: row.id,
    username: row.username,
    passwordHash: row.password_hash,
    isAdmin: Boolean(row.is_admin),
    createdAt: new Date(row.created_at),
    avatarMime: row.avatar_mime ?? undefined,
  };
}

export function userApiToRow(user: User): UserRow {
  return {
    id: user.id,
    username: user.username,
    password_hash: user.passwordHash,
    is_admin: user.isAdmin ? 1 : 0,
    created_at: user.createdAt.toISOString(),
    avatar_mime: user.avatarMime ?? null,
  };
}

export interface CommentRow {
  id: string;
  dump_id: string;
  user_id: string;
  parent_id: string | null;
  body: string;
  created_at: string;
  deleted: number;
  author_username: string;
  author_avatar_mime: string | null;
  [key: string]: SQLOutputValue;
}

export function isCommentRow(obj: Record<string, SQLOutputValue>): obj is CommentRow {
  return !!obj && typeof obj === "object" &&
    typeof obj.id === "string" &&
    typeof obj.dump_id === "string" &&
    typeof obj.user_id === "string" &&
    (typeof obj.parent_id === "string" || obj.parent_id === null) &&
    typeof obj.body === "string" &&
    typeof obj.created_at === "string" &&
    typeof obj.deleted === "number" &&
    typeof obj.author_username === "string" &&
    (typeof obj.author_avatar_mime === "string" || obj.author_avatar_mime === null);
}

export function commentRowToApi(row: CommentRow): Comment {
  return {
    id: row.id,
    dumpId: row.dump_id,
    userId: row.user_id,
    parentId: row.parent_id ?? undefined,
    body: row.body,
    createdAt: new Date(row.created_at),
    deleted: Boolean(row.deleted),
    authorUsername: row.author_username,
    authorAvatarMime: row.author_avatar_mime ?? undefined,
  };
}

export interface PlaylistRow {
  id: string;
  user_id: string;
  title: string;
  description: string | null;
  is_public: number;
  created_at: string;
  image_mime: string | null;
  [key: string]: SQLOutputValue;
}

export function isPlaylistRow(
  obj: Record<string, SQLOutputValue>,
): obj is PlaylistRow {
  return !!obj && typeof obj.id === "string" &&
    typeof obj.user_id === "string" &&
    typeof obj.title === "string" &&
    typeof obj.is_public === "number" &&
    typeof obj.created_at === "string";
}

export function playlistRowToApi(row: PlaylistRow): Playlist {
  return {
    id: row.id,
    userId: row.user_id,
    title: row.title,
    description: row.description ?? undefined,
    isPublic: Boolean(row.is_public),
    createdAt: new Date(row.created_at),
    imageMime: row.image_mime ?? undefined,
    dumpCount: typeof row.dump_count === "number" ? row.dump_count : undefined,
  };
}