-- Create metrics table
CREATE TABLE IF NOT EXISTS metrics (
    id SERIAL PRIMARY KEY,
    server_id VARCHAR(255) NOT NULL,
    timestamp TIMESTAMP WITH TIME ZONE NOT NULL DEFAULT NOW(),
    cpu_usage DECIMAL(5,2),
    cpu_cores INTEGER,
    memory_total DECIMAL(10,2),
    memory_used DECIMAL(10,2),
    memory_available DECIMAL(10,2),
    memory_percent DECIMAL(5,2),
    disk_total DECIMAL(10,2),
    disk_used DECIMAL(10,2),
    disk_free DECIMAL(10,2),
    disk_percent DECIMAL(5,2),
    disks JSONB,
    network_rx DECIMAL(10,2),
    network_tx DECIMAL(10,2),
    network_rx_total DECIMAL(10,2),
    network_tx_total DECIMAL(10,2),
    created_at TIMESTAMP WITH TIME ZONE NOT NULL DEFAULT NOW()
);

-- Create indexes for better query performance
CREATE INDEX IF NOT EXISTS idx_metrics_server_id ON metrics(server_id);
CREATE INDEX IF NOT EXISTS idx_metrics_timestamp ON metrics(timestamp);
CREATE INDEX IF NOT EXISTS idx_metrics_server_timestamp ON metrics(server_id, timestamp DESC);

-- Migration: Add disks column if it doesn't exist (for existing databases)
DO $$
BEGIN
    IF NOT EXISTS (
        SELECT 1 FROM information_schema.columns 
        WHERE table_name = 'metrics' AND column_name = 'disks'
    ) THEN
        ALTER TABLE metrics ADD COLUMN disks JSONB;
        CREATE INDEX IF NOT EXISTS idx_metrics_disks ON metrics USING GIN (disks);
    END IF;
END $$;

-- Create index for disks column (will be created if column exists)
CREATE INDEX IF NOT EXISTS idx_metrics_disks ON metrics USING GIN (disks);

-- Migration: Add load average columns if they don't exist
DO $$
BEGIN
    IF NOT EXISTS (
        SELECT 1 FROM information_schema.columns 
        WHERE table_name = 'metrics' AND column_name = 'load_avg_1min'
    ) THEN
        ALTER TABLE metrics ADD COLUMN load_avg_1min DECIMAL(5,2);
        ALTER TABLE metrics ADD COLUMN load_avg_5min DECIMAL(5,2);
        ALTER TABLE metrics ADD COLUMN load_avg_15min DECIMAL(5,2);
    END IF;
END $$;

-- Migration: Add swap columns if they don't exist
DO $$
BEGIN
    IF NOT EXISTS (
        SELECT 1 FROM information_schema.columns 
        WHERE table_name = 'metrics' AND column_name = 'swap_total'
    ) THEN
        ALTER TABLE metrics ADD COLUMN swap_total DECIMAL(10,2);
        ALTER TABLE metrics ADD COLUMN swap_used DECIMAL(10,2);
        ALTER TABLE metrics ADD COLUMN swap_free DECIMAL(10,2);
        ALTER TABLE metrics ADD COLUMN swap_percent DECIMAL(5,2);
    END IF;
END $$;

-- Migration: Add process_count and uptime columns if they don't exist
DO $$
BEGIN
    IF NOT EXISTS (
        SELECT 1 FROM information_schema.columns 
        WHERE table_name = 'metrics' AND column_name = 'process_count'
    ) THEN
        ALTER TABLE metrics ADD COLUMN process_count INTEGER;
        ALTER TABLE metrics ADD COLUMN uptime_seconds DECIMAL(10,2);
    END IF;
END $$;

-- Create servers table to track server metadata
CREATE TABLE IF NOT EXISTS servers (
    server_id VARCHAR(255) PRIMARY KEY,
    hostname VARCHAR(255),
    first_seen TIMESTAMP WITH TIME ZONE NOT NULL DEFAULT NOW(),
    last_seen TIMESTAMP WITH TIME ZONE NOT NULL DEFAULT NOW(),
    total_metrics_count INTEGER DEFAULT 0
);

-- Create function to update server last_seen and metrics count
CREATE OR REPLACE FUNCTION update_server_stats()
RETURNS TRIGGER AS $$
BEGIN
    INSERT INTO servers (server_id, hostname, first_seen, last_seen, total_metrics_count)
    VALUES (NEW.server_id, NEW.server_id, NOW(), NOW(), 1)
    ON CONFLICT (server_id) DO UPDATE
    SET last_seen = NOW(),
        total_metrics_count = servers.total_metrics_count + 1;
    RETURN NEW;
END;
$$ LANGUAGE plpgsql;

-- Create trigger to automatically update server stats
DROP TRIGGER IF EXISTS trigger_update_server_stats ON metrics;
CREATE TRIGGER trigger_update_server_stats
    AFTER INSERT ON metrics
    FOR EACH ROW
    EXECUTE FUNCTION update_server_stats();

-- Create API keys table for client authentication
CREATE TABLE IF NOT EXISTS api_keys (
    id SERIAL PRIMARY KEY,
    key_hash VARCHAR(255) NOT NULL UNIQUE,
    server_id VARCHAR(255),
    name VARCHAR(255),
    created_at TIMESTAMP WITH TIME ZONE NOT NULL DEFAULT NOW(),
    last_used TIMESTAMP WITH TIME ZONE,
    is_active BOOLEAN DEFAULT TRUE
);

CREATE INDEX IF NOT EXISTS idx_api_keys_hash ON api_keys(key_hash);
CREATE INDEX IF NOT EXISTS idx_api_keys_server_id ON api_keys(server_id);