import sqlite3 from 'better-sqlite3'
import * as z from 'zod'

const zMatter = z.object({
  date: z.date().optional(),
  createdAt: z.date().optional(),
  updatedAt: z.date().optional(),
  title: z.string(),
  image: z.string().optional(),
  tag: z.array(z.string()).optional(),
  category: z.string().optional(),
})

export type IMatter = z.infer<typeof zMatter>

export const zPost = z
  .object({
    path: z.string(),
    /**
     * Cleaned and jieba-separated markdown
     */
    content: z.string(),
    excerptHtml: z.string(),
    contentHtml: z.string(),
  })
  .merge(zMatter.nonstrict())

export type IPost = z.infer<typeof zPost>

export class Database {
  db: sqlite3.Database

  constructor(public filepath: string, opts?: sqlite3.Options) {
    this.db = sqlite3(filepath, opts)
  }

  public init(): void {
    this.db.exec(/* sql */ `
    CREATE TABLE IF NOT EXISTS files (
      [path]        TEXT PRIMARY KEY,
      [date]        INT,    -- epoch milli
      [createdAt]   INT,    -- epoch milli
      [updatedAt]   INT,    -- epoch milli
      -- q.title
      [image]       TEXT,
      -- q.tag.split(/ /g)
      -- q.category
      -- q.content
      excerptHtml   TEXT NOT NULL,
      contentHtml   TEXT NOT NULL
    );

    CREATE INDEX IF NOT EXISTS files_date ON files([date]);
    CREATE INDEX IF NOT EXISTS files_createdAt ON files(createdAt);
    CREATE INDEX IF NOT EXISTS files_updatedAt ON files(updatedAt);
    `)

    this.db.exec(/* sql */ `
    CREATE VIRTUAL TABLE IF NOT EXISTS q USING fts5 (
      [path],       -- REFERENCES files([path])
      title,
      tag,          -- space separated
      category,     -- can compare via equal
      content       -- cleaned markdown
    );
    `)
  }

  public insert(...ps: IPost[]): void {
    const fStmt = this.db.prepare(/* sql */ `
    INSERT INTO files ([path], [date], [createdAt], [updatedAt], [image], excerptHtml, contentHtml)
    VALUES (@path, @date, @createdAt, @updatedAt, @image, @excerptHtml, @contentHtml)
    `)

    const qStmt = this.db.prepare(/* sql */ `
    INSERT INTO q ([path], title, tag, category, content)
    VALUES (@path, @title, @tag, @category, @content)
    `)

    this.db.transaction(() => {
      // eslint-disable-next-line array-callback-return
      ps.map((p) => {
        p = zPost.parse(p)

        fStmt.run({
          ...p,
          date: p.date ? p.date.getTime() : undefined,
          createdAt: p.createdAt ? p.createdAt.getTime() : undefined,
          updatedAt: p.updatedAt ? p.updatedAt.getTime() : undefined,
        })

        qStmt.run({
          ...p,
          tag: p.tag ? p.tag.join(' ') : undefined,
        })
      })
    })()
  }
}