import { db } from '../db/index.js';
import type { BetaRow } from './beta.js';
import { serverTitle } from '../../ui/server-labels.js';

const positive = (value: string | null, fallback: number) => {
    const number = Number(value);
    return Number.isSafeInteger(number) && number > 0 ? number : fallback;
};

export function betaListPage(params: URLSearchParams) {
    const state = params.get('state'),
        view = params.get('view'),
        search = (params.get('q') ?? '').slice(0, 200).trim();
    const predicates: string[] = [],
        args: (string | number)[] = [];
    if (state) {
        predicates.push('b.state=?');
        args.push(state);
    } else if (view === 'active') predicates.push("b.state IN ('running','ready-promote')");
    else if (view === 'history') predicates.push("b.state IN ('promoted','rolled-back')");
    const status = params.get('status');
    if (
        status &&
        ['ready', 'testing', 'attention', 'paused', 'promoted', 'rolled-back'].includes(status)
    ) {
        // Match betaStatus: closed lifecycle wins over the final test outcome.
        predicates.push(`(CASE WHEN b.state IN ('promoted','rolled-back') THEN b.state
            WHEN EXISTS (SELECT 1 FROM beta_servers m WHERE m.beta_id=b.id AND (m.server_deleted_at IS NOT NULL OR m.stage='failed'))
                OR EXISTS (SELECT 1 FROM beta_test_plans p WHERE p.beta_id=b.id AND p.outcome IN ('failed','inconclusive')) THEN 'attention'
            WHEN EXISTS (SELECT 1 FROM beta_test_plans p WHERE p.beta_id=b.id AND p.outcome='paused') THEN 'paused'
            WHEN b.state='ready-promote' THEN 'ready' ELSE 'testing' END)=?`);
        args.push(status);
    }
    if (search) {
        const names = (
            db().prepare('SELECT DISTINCT server FROM beta_servers').all() as { server: string }[]
        )
            .filter((row) =>
                `${row.server} ${serverTitle(row.server)}`
                    .toLowerCase()
                    .includes(search.toLowerCase())
            )
            .map((row) => row.server);
        predicates.push(`(instr(lower('#'||b.id||' '||COALESCE(b.notes,'')),lower(?))>0 OR EXISTS (
            SELECT 1 FROM beta_scripts bs JOIN scripts s ON s.id=bs.script_id WHERE bs.beta_id=b.id AND (instr(lower(s.name),lower(?))>0 OR instr(lower(s.target_rel_path),lower(?))>0))
            OR EXISTS (SELECT 1 FROM scripts s WHERE s.id=b.script_id AND (instr(lower(s.name),lower(?))>0 OR instr(lower(s.target_rel_path),lower(?))>0))
            OR EXISTS (SELECT 1 FROM beta_servers m WHERE m.beta_id=b.id AND m.server IN (SELECT value FROM json_each(?))))`);
        args.push(search, search, search, search, search, JSON.stringify(names));
    }
    const where = predicates.length ? ' WHERE ' + predicates.join(' AND ') : '';
    const total = (
        db()
            .prepare('SELECT COUNT(*) n FROM betas b' + where)
            .get(...args) as { n: number }
    ).n;
    const pageSize = Math.min(100, positive(params.get('limit'), 25));
    const totalPages = Math.max(1, Math.ceil(total / pageSize));
    const page = Math.min(totalPages, positive(params.get('page'), 1));
    const betas = db()
        .prepare('SELECT b.* FROM betas b' + where + ' ORDER BY b.id DESC LIMIT ? OFFSET ?')
        .all(...args, pageSize, (page - 1) * pageSize) as BetaRow[];
    const counts = db()
        .prepare(
            `SELECT COUNT(CASE WHEN state IN ('running','ready-promote') THEN 1 END) active,
        COUNT(CASE WHEN state IN ('promoted','rolled-back') THEN 1 END) history FROM betas`
        )
        .get() as { active: number; history: number };
    return { betas, page, pageSize, total, totalPages, counts };
}

export function betaActivityPage(id: number, params = new URLSearchParams()) {
    const before = positive(params.get('before'), Number.MAX_SAFE_INTEGER);
    const limit = Math.min(100, positive(params.get('limit'), 50));
    const rows = db()
        .prepare(
            'SELECT id,created_at,message FROM beta_events WHERE beta_id=? AND id<? ORDER BY id DESC LIMIT ?'
        )
        .all(id, before, limit + 1) as { id: number; created_at: string; message: string }[];
    const more = rows.length > limit;
    const events = rows.slice(0, limit).reverse();
    return { events, nextBefore: more ? events[0].id : null };
}