CREATE EXTENSION IF NOT EXISTS "uuid-ossp";

CREATE TYPE user_role AS ENUM ('user', 'admin');

CREATE TABLE IF NOT EXISTS users (
    id UUID PRIMARY KEY DEFAULT uuid_generate_v4(),
    github_id BIGINT NOT NULL UNIQUE,
    email TEXT,
    name TEXT NOT NULL,
    avatar_url TEXT,
    role user_role NOT NULL DEFAULT 'user',
    created_at TIMESTAMPTZ NOT NULL DEFAULT NOW(),
    updated_at TIMESTAMPTZ NOT NULL DEFAULT NOW()
);

CREATE TABLE IF NOT EXISTS posts (
    id UUID PRIMARY KEY DEFAULT uuid_generate_v4(),
    slug TEXT NOT NULL UNIQUE,
    title TEXT NOT NULL,
    summary TEXT,
    content_md TEXT NOT NULL DEFAULT '',
    content_html TEXT NOT NULL DEFAULT '',
    tags TEXT[] NOT NULL DEFAULT '{}',
    status TEXT NOT NULL DEFAULT 'draft',
    author_id UUID NOT NULL REFERENCES users(id) ON DELETE CASCADE,
    created_at TIMESTAMPTZ NOT NULL DEFAULT NOW(),
    updated_at TIMESTAMPTZ NOT NULL DEFAULT NOW(),
    published_at TIMESTAMPTZ,
    CONSTRAINT valid_status CHECK (status IN ('draft', 'private', 'public'))
);

CREATE TABLE IF NOT EXISTS drafts (
    id UUID PRIMARY KEY DEFAULT uuid_generate_v4(),
    post_id UUID NOT NULL UNIQUE REFERENCES posts(id) ON DELETE CASCADE,
    content_md TEXT NOT NULL DEFAULT '',
    updated_at TIMESTAMPTZ NOT NULL DEFAULT NOW()
);

CREATE TABLE IF NOT EXISTS comments (
    id UUID PRIMARY KEY DEFAULT uuid_generate_v4(),
    post_id UUID NOT NULL REFERENCES posts(id) ON DELETE CASCADE,
    user_id UUID NOT NULL REFERENCES users(id) ON DELETE CASCADE,
    content TEXT NOT NULL,
    created_at TIMESTAMPTZ NOT NULL DEFAULT NOW(),
    updated_at TIMESTAMPTZ NOT NULL DEFAULT NOW(),
    deleted_at TIMESTAMPTZ
);

CREATE INDEX IF NOT EXISTS idx_posts_status_published_at ON posts(status, published_at DESC NULLS LAST);
CREATE INDEX IF NOT EXISTS idx_posts_slug ON posts(slug);
CREATE INDEX IF NOT EXISTS idx_posts_tags ON posts USING GIN(tags);
CREATE INDEX IF NOT EXISTS idx_comments_post_id ON comments(post_id, created_at DESC);
CREATE INDEX IF NOT EXISTS idx_drafts_post_id ON drafts(post_id);
CREATE INDEX IF NOT EXISTS idx_users_github_id ON users(github_id);