package database

import (
	"context"
	"fmt"

	"github.com/jackc/pgx/v5/pgxpool"
)

type DB struct {
	Pool *pgxpool.Pool
}

func New(dsn string) (*DB, error) {
	pool, err := pgxpool.New(context.Background(), dsn)
	if err != nil {
		return nil, fmt.Errorf("connect to postgres: %w", err)
	}

	if err := pool.Ping(context.Background()); err != nil {
		pool.Close()
		return nil, fmt.Errorf("ping postgres: %w", err)
	}

	db := &DB{Pool: pool}
	if err := db.migrate(); err != nil {
		pool.Close()
		return nil, fmt.Errorf("run migrations: %w", err)
	}

	return db, nil
}

func (db *DB) Close() {
	db.Pool.Close()
}

func (db *DB) migrate() error {
	ctx := context.Background()

	_, err := db.Pool.Exec(ctx, `
		CREATE TABLE IF NOT EXISTS remotes (
			name            TEXT PRIMARY KEY,
			package_type    TEXT NOT NULL,
			repo_type       TEXT DEFAULT 'remote',
			base_url        TEXT NOT NULL DEFAULT '',
			description     TEXT DEFAULT '',
			username        TEXT DEFAULT '',
			password        TEXT DEFAULT '',
			immutable_ttl   INTEGER DEFAULT 0,
			mutable_ttl     INTEGER DEFAULT 3600,
			check_mutable   BOOLEAN DEFAULT TRUE,
			patterns            TEXT[] DEFAULT '{}',
			blocklist           TEXT[] DEFAULT '{}',
			mutable_patterns    TEXT[] DEFAULT '{}',
			immutable_patterns  TEXT[] DEFAULT '{}',
			ban_tags_enabled    BOOLEAN DEFAULT FALSE,
			ban_tags            TEXT[] DEFAULT '{}',
			quarantine_enabled  BOOLEAN DEFAULT FALSE,
			quarantine_days     INTEGER DEFAULT 3,
			stale_on_error      BOOLEAN DEFAULT TRUE,
			releases_remote     TEXT DEFAULT '',
			managed_by          TEXT DEFAULT '',
			created_at      TIMESTAMPTZ DEFAULT NOW(),
			updated_at      TIMESTAMPTZ DEFAULT NOW()
		);

		CREATE TABLE IF NOT EXISTS virtuals (
			name            TEXT PRIMARY KEY,
			package_type    TEXT NOT NULL,
			description     TEXT DEFAULT '',
			members         TEXT[] NOT NULL,
			managed_by      TEXT DEFAULT '',
			created_at      TIMESTAMPTZ DEFAULT NOW(),
			updated_at      TIMESTAMPTZ DEFAULT NOW()
		);

		CREATE TABLE IF NOT EXISTS blobs (
			content_hash    TEXT PRIMARY KEY,
			s3_key          TEXT NOT NULL,
			size_bytes      BIGINT NOT NULL,
			content_type    TEXT DEFAULT 'application/octet-stream',
			created_at      TIMESTAMPTZ DEFAULT NOW()
		);

		CREATE TABLE IF NOT EXISTS artifacts (
			id              BIGSERIAL PRIMARY KEY,
			remote_name     TEXT NOT NULL REFERENCES remotes(name) ON DELETE CASCADE,
			path            TEXT NOT NULL,
			content_hash    TEXT NOT NULL REFERENCES blobs(content_hash),
			upstream_etag   TEXT DEFAULT '',
			upstream_last_modified TIMESTAMPTZ,
			first_seen_at   TIMESTAMPTZ DEFAULT NOW(),
			last_fetched_at TIMESTAMPTZ DEFAULT NOW(),
			last_accessed_at TIMESTAMPTZ DEFAULT NOW(),
			fetch_count     BIGINT DEFAULT 1,
			access_count    BIGINT DEFAULT 1,
			UNIQUE(remote_name, path)
		);

		CREATE INDEX IF NOT EXISTS idx_artifacts_remote ON artifacts(remote_name);
		CREATE INDEX IF NOT EXISTS idx_artifacts_last_accessed ON artifacts(last_accessed_at);

		CREATE TABLE IF NOT EXISTS local_files (
			id              BIGSERIAL PRIMARY KEY,
			repo_name       TEXT NOT NULL,
			file_path       TEXT NOT NULL,
			content_hash    TEXT NOT NULL REFERENCES blobs(content_hash),
			created_at      TIMESTAMPTZ DEFAULT NOW(),
			UNIQUE(repo_name, file_path)
		);

		CREATE TABLE IF NOT EXISTS access_log (
			id              BIGSERIAL PRIMARY KEY,
			remote_name     TEXT NOT NULL,
			path            TEXT NOT NULL,
			cache_hit       BOOLEAN NOT NULL,
			size_bytes      BIGINT DEFAULT 0,
			upstream_ms     INTEGER DEFAULT 0,
			client_ip       TEXT DEFAULT '',
			created_at      TIMESTAMPTZ DEFAULT NOW()
		);

		CREATE INDEX IF NOT EXISTS idx_access_log_remote_time ON access_log(remote_name, created_at);

		ALTER TABLE remotes ADD COLUMN IF NOT EXISTS repo_type TEXT DEFAULT 'remote';
	`)
	return err
}