const test = require('node:test');
const assert = require('node:assert/strict');

require('../src/common');

const { getPendingMigrations } = require('../src/db/migrations');

function createPool(responses) {
  const queries = [];
  return {
    queries,
    async query(sql, params) {
      queries.push([sql, params]);
      const text = String(sql);
      for (const response of responses) {
        if (response.match(text, params)) {
          return response.result;
        }
      }
      return [[]];
    }
  };
}

test('pending migrations are empty when the schema already matches the app version', async () => {
  const pool = createPool([
    {
      match(sql) {
        return sql.includes('FROM information_schema.COLUMNS') && sql.includes('TABLE_NAME = ?') && sql.includes('COLUMN_NAME = ?');
      },
      result: [[{ column_count: 0 }]]
    },
    {
      match(_sql, params) {
        return Array.isArray(params) && params[0] === 'i_schedule_groups';
      },
      result: [[{ table_count: 0 }]]
    },
    {
      match(_sql, params) {
        return Array.isArray(params) && params[0] === 'i_schedule_entries';
      },
      result: [[{ table_count: 0 }]]
    }
  ]);

  const pendingMigrations = await getPendingMigrations(pool, { currentVersion: '2.11.1' });

  assert.equal(pendingMigrations.length, 0);
});

test('pending migrations are reported when an older schema still needs scripts', async () => {
  const pool = createPool([
    {
      match(sql) {
        return sql.includes('FROM information_schema.COLUMNS') && sql.includes('TABLE_NAME = ?') && sql.includes('COLUMN_NAME = ?');
      },
      result: [[{ column_count: 0 }]]
    },
    {
      match(_sql, params) {
        return Array.isArray(params) && params[0] === 'i_schedule_groups';
      },
      result: [[{ table_count: 1 }]]
    },
    {
      match(_sql, params) {
        return Array.isArray(params) && params[0] === 'i_schedule_entries';
      },
      result: [[{ table_count: 1 }]]
    }
  ]);

  const pendingMigrations = await getPendingMigrations(pool, { currentVersion: '2.6.17' });

  assert.ok(pendingMigrations.length > 0);
  assert.equal(pendingMigrations.filter(function (migration) { return migration.version.indexOf('2.8.') === 0; }).length, 4);
  assert.equal(pendingMigrations.find(function (migration) { return migration.version.indexOf('2.8.') === 0; }).version, '2.8.0');
});

test('a partial timetable schema does not fast-forward migration detection', async () => {
  const pool = createPool([
    {
      match(sql) {
        return sql.includes('FROM information_schema.COLUMNS') && sql.includes('TABLE_NAME = ?') && sql.includes('COLUMN_NAME = ?');
      },
      result: [[{ column_count: 0 }]]
    },
    {
      match(_sql, params) {
        return Array.isArray(params) && params[0] === 'i_timetable_groups';
      },
      result: [[{ table_count: 1 }]]
    },
    {
      match(_sql, params) {
        return Array.isArray(params) && params[0] === 'i_timetable_entries';
      },
      result: [[{ table_count: 0 }]]
    },
    {
      match(_sql, params) {
        return Array.isArray(params) && params[0] === 'i_schedule_groups';
      },
      result: [[{ table_count: 0 }]]
    },
    {
      match(_sql, params) {
        return Array.isArray(params) && params[0] === 'i_schedule_entries';
      },
      result: [[{ table_count: 0 }]]
    }
  ]);

  const pendingMigrations = await getPendingMigrations(pool, { currentVersion: '0.0.0' });

  assert.ok(pendingMigrations.some(function (migration) { return migration.version === '2.6.16'; }));
  assert.ok(pendingMigrations.some(function (migration) { return migration.version === '2.6.17'; }));
  assert.ok(pendingMigrations.some(function (migration) { return migration.version === '2.6.18'; }));
});