CREATE EXTENSION IF NOT EXISTS "pgcrypto";

-- =============================================================
-- Players: all known Telegram users who interact with the bot
-- =============================================================
CREATE TABLE players (
    id                  UUID PRIMARY KEY DEFAULT gen_random_uuid(),
    telegram_id         BIGINT NOT NULL UNIQUE,
    display_name        VARCHAR(255) NOT NULL,
    telegram_username   VARCHAR(255),
    created_at          TIMESTAMPTZ NOT NULL DEFAULT now()
);

-- =============================================================
-- Game groups: Telegram group chats where games are organized
-- =============================================================
CREATE TABLE game_groups (
    id                  UUID PRIMARY KEY DEFAULT gen_random_uuid(),
    telegram_chat_id    BIGINT NOT NULL UNIQUE,
    name                VARCHAR(255) NOT NULL,
    gm_telegram_id      BIGINT NOT NULL,
    created_at          TIMESTAMPTZ NOT NULL DEFAULT now()
);

-- =============================================================
-- Group membership: which players belong to which groups
-- =============================================================
CREATE TABLE game_group_members (
    id          UUID PRIMARY KEY DEFAULT gen_random_uuid(),
    group_id    UUID NOT NULL REFERENCES game_groups(id) ON DELETE CASCADE,
    player_id   UUID NOT NULL REFERENCES players(id) ON DELETE CASCADE,
    is_gm       BOOLEAN NOT NULL DEFAULT false,
    joined_at   TIMESTAMPTZ NOT NULL DEFAULT now(),
    UNIQUE (group_id, player_id)
);

-- =============================================================
-- Sessions: individual game sessions with scheduling
-- =============================================================
CREATE TABLE sessions (
    id                          UUID PRIMARY KEY DEFAULT gen_random_uuid(),
    group_id                    UUID NOT NULL REFERENCES game_groups(id) ON DELETE CASCADE,
    title                       VARCHAR(500) NOT NULL,
    join_link                   TEXT NOT NULL,
    scheduled_at                TIMESTAMPTZ NOT NULL,
    status                      VARCHAR(50) NOT NULL DEFAULT 'Planned'
                                CHECK (status IN ('Planned','ConfirmationSent','Confirmed','Cancelled')),
    confirmation_message_id     INTEGER,
    link_message_id             INTEGER,
    created_at                  TIMESTAMPTZ NOT NULL DEFAULT now(),
    updated_at                  TIMESTAMPTZ NOT NULL DEFAULT now()
);

-- Partial index: only scan sessions that still need processing
CREATE INDEX ix_sessions_pending ON sessions (scheduled_at)
    WHERE status IN ('Planned', 'ConfirmationSent', 'Confirmed');

-- =============================================================
-- Session participants: per-session RSVP tracking
-- =============================================================
CREATE TABLE session_participants (
    id              UUID PRIMARY KEY DEFAULT gen_random_uuid(),
    session_id      UUID NOT NULL REFERENCES sessions(id) ON DELETE CASCADE,
    player_id       UUID NOT NULL REFERENCES players(id) ON DELETE CASCADE,
    is_gm           BOOLEAN NOT NULL DEFAULT false,
    rsvp_status     VARCHAR(50) NOT NULL DEFAULT 'Pending'
                    CHECK (rsvp_status IN ('Pending','Confirmed','Declined')),
    responded_at    TIMESTAMPTZ,
    UNIQUE (session_id, player_id)
);