-- Pickleball ELO Tracker Database Schema
-- Glicko-2 Rating System with Singles/Doubles tracking

-- Enable foreign keys
PRAGMA foreign_keys = ON;

-- Players table
CREATE TABLE IF NOT EXISTS players (
    id INTEGER PRIMARY KEY AUTOINCREMENT,
    name TEXT NOT NULL UNIQUE,
    email TEXT,
    
    -- Singles Glicko-2 values
    singles_rating REAL NOT NULL DEFAULT 1500.0,
    singles_rd REAL NOT NULL DEFAULT 350.0,
    singles_volatility REAL NOT NULL DEFAULT 0.06,
    
    -- Doubles Glicko-2 values
    doubles_rating REAL NOT NULL DEFAULT 1500.0,
    doubles_rd REAL NOT NULL DEFAULT 350.0,
    doubles_volatility REAL NOT NULL DEFAULT 0.06,
    
    -- Metadata
    created_at TEXT NOT NULL DEFAULT (datetime('now')),
    last_played TEXT NOT NULL DEFAULT (datetime('now'))
);

-- Sessions (rating periods)
CREATE TABLE IF NOT EXISTS sessions (
    id INTEGER PRIMARY KEY AUTOINCREMENT,
    start_time TEXT NOT NULL DEFAULT (datetime('now')),
    end_time TEXT,
    summary_sent BOOLEAN NOT NULL DEFAULT 0,
    notes TEXT
);

-- Matches
CREATE TABLE IF NOT EXISTS matches (
    id INTEGER PRIMARY KEY AUTOINCREMENT,
    session_id INTEGER NOT NULL,
    match_type TEXT NOT NULL CHECK(match_type IN ('singles', 'doubles')),
    timestamp TEXT NOT NULL DEFAULT (datetime('now')),
    team1_score INTEGER NOT NULL,
    team2_score INTEGER NOT NULL,
    
    FOREIGN KEY (session_id) REFERENCES sessions(id) ON DELETE CASCADE
);

-- Match participants (links players to matches with rating changes)
CREATE TABLE IF NOT EXISTS match_participants (
    id INTEGER PRIMARY KEY AUTOINCREMENT,
    match_id INTEGER NOT NULL,
    player_id INTEGER NOT NULL,
    team INTEGER NOT NULL CHECK(team IN (1, 2)),
    
    -- Pre-match Glicko-2 values
    rating_before REAL NOT NULL,
    rd_before REAL NOT NULL,
    volatility_before REAL NOT NULL,
    
    -- Post-match Glicko-2 values
    rating_after REAL NOT NULL,
    rd_after REAL NOT NULL,
    volatility_after REAL NOT NULL,
    
    -- Calculated change
    rating_change REAL NOT NULL,
    
    FOREIGN KEY (match_id) REFERENCES matches(id) ON DELETE CASCADE,
    FOREIGN KEY (player_id) REFERENCES players(id) ON DELETE CASCADE
);

-- Indexes for performance
CREATE INDEX IF NOT EXISTS idx_matches_session ON matches(session_id);
CREATE INDEX IF NOT EXISTS idx_matches_timestamp ON matches(timestamp DESC);
CREATE INDEX IF NOT EXISTS idx_participants_match ON match_participants(match_id);
CREATE INDEX IF NOT EXISTS idx_participants_player ON match_participants(player_id);
CREATE INDEX IF NOT EXISTS idx_players_name ON players(name);
CREATE INDEX IF NOT EXISTS idx_players_singles_rating ON players(singles_rating DESC);
CREATE INDEX IF NOT EXISTS idx_players_doubles_rating ON players(doubles_rating DESC);