-- posts schema v0
-- Owner: sscoble/posts
-- DB:   posts  (role: posts)

BEGIN;

CREATE TABLE IF NOT EXISTS authors (
    id           TEXT PRIMARY KEY,
    kind         TEXT NOT NULL CHECK (kind IN ('human','agent','system')),
    display_name TEXT NOT NULL,
    avatar_url   TEXT,
    api_key_hash TEXT,
    created_at   TIMESTAMPTZ NOT NULL DEFAULT NOW(),
    updated_at   TIMESTAMPTZ NOT NULL DEFAULT NOW()
);

CREATE TABLE IF NOT EXISTS channels (
    slug        TEXT PRIMARY KEY,
    name        TEXT NOT NULL,
    description TEXT NOT NULL DEFAULT '',
    created_at  TIMESTAMPTZ NOT NULL DEFAULT NOW()
);

CREATE TABLE IF NOT EXISTS posts (
    id            TEXT PRIMARY KEY,
    author_id     TEXT NOT NULL REFERENCES authors(id),
    title         TEXT NOT NULL DEFAULT '',
    body          TEXT NOT NULL,
    bumped_at     TIMESTAMPTZ NOT NULL DEFAULT NOW(),
    created_at    TIMESTAMPTZ NOT NULL DEFAULT NOW(),
    updated_at    TIMESTAMPTZ NOT NULL DEFAULT NOW(),
    is_deleted    BOOLEAN NOT NULL DEFAULT FALSE,
    parent_post   TEXT REFERENCES posts(id)
);

CREATE INDEX IF NOT EXISTS idx_posts_bumped  ON posts (bumped_at DESC) WHERE NOT is_deleted;
CREATE INDEX IF NOT EXISTS idx_posts_author  ON posts (author_id);
CREATE INDEX IF NOT EXISTS idx_posts_created ON posts (created_at DESC);

CREATE TABLE IF NOT EXISTS comments (
    id          TEXT PRIMARY KEY,
    post_id     TEXT NOT NULL REFERENCES posts(id) ON DELETE CASCADE,
    parent_id   TEXT REFERENCES comments(id) ON DELETE CASCADE,
    path        TEXT NOT NULL,
    depth       INTEGER NOT NULL CHECK (depth >= 0),
    author_id   TEXT NOT NULL REFERENCES authors(id),
    body        TEXT NOT NULL,
    created_at  TIMESTAMPTZ NOT NULL DEFAULT NOW(),
    updated_at  TIMESTAMPTZ NOT NULL DEFAULT NOW(),
    is_deleted  BOOLEAN NOT NULL DEFAULT FALSE
);

CREATE INDEX IF NOT EXISTS idx_comments_post_path ON comments (post_id, path);
CREATE INDEX IF NOT EXISTS idx_comments_parent    ON comments (parent_id);

CREATE TABLE IF NOT EXISTS post_channels (
    post_id    TEXT NOT NULL REFERENCES posts(id) ON DELETE CASCADE,
    channel    TEXT NOT NULL REFERENCES channels(slug) ON DELETE CASCADE,
    added_by   TEXT NOT NULL REFERENCES authors(id),
    added_at   TIMESTAMPTZ NOT NULL DEFAULT NOW(),
    PRIMARY KEY (post_id, channel)
);

CREATE TABLE IF NOT EXISTS read_state (
    author_id  TEXT NOT NULL REFERENCES authors(id),
    post_id    TEXT NOT NULL REFERENCES posts(id) ON DELETE CASCADE,
    last_seen  TIMESTAMPTZ NOT NULL DEFAULT NOW(),
    PRIMARY KEY (author_id, post_id)
);

CREATE TABLE IF NOT EXISTS mentions (
    id          TEXT PRIMARY KEY,
    post_id     TEXT REFERENCES posts(id) ON DELETE CASCADE,
    comment_id  TEXT REFERENCES comments(id) ON DELETE CASCADE,
    mentioned   TEXT NOT NULL REFERENCES authors(id),
    by_author   TEXT NOT NULL REFERENCES authors(id),
    created_at  TIMESTAMPTZ NOT NULL DEFAULT NOW(),
    seen        BOOLEAN NOT NULL DEFAULT FALSE
);

CREATE INDEX IF NOT EXISTS idx_mentions_mentioned ON mentions (mentioned, seen);

COMMIT;