<?php

namespace App\Database\Migrations;

use CodeIgniter\Database\Migration;

class CreateParentPolicyAcceptances extends Migration
{
    public function up(): void
    {
        if ($this->db->tableExists('parent_policy_acceptances')) {
            return;
        }

        $this->forge->addField([
            'id' => [
                'type' => 'INT',
                'constraint' => 11,
                'unsigned' => true,
                'auto_increment' => true,
            ],
            'parent_id' => [
                'type' => 'INT',
                'constraint' => 11,
                'unsigned' => true,
                'null' => false,
            ],
            'school_year' => [
                'type' => 'VARCHAR',
                'constraint' => 9,
                'null' => false,
            ],
            'accepted_at' => [
                'type' => 'DATETIME',
                'null' => false,
            ],
            'source' => [
                'type' => 'VARCHAR',
                'constraint' => 40,
                'null' => false,
                'default' => 'registration',
            ],
            'ip_address' => [
                'type' => 'VARCHAR',
                'constraint' => 45,
                'null' => true,
            ],
            'user_agent' => [
                'type' => 'VARCHAR',
                'constraint' => 255,
                'null' => true,
            ],
            'created_at' => [
                'type' => 'DATETIME',
                'null' => true,
            ],
            'updated_at' => [
                'type' => 'DATETIME',
                'null' => true,
            ],
        ]);

        $this->forge->addKey('id', true);
        $this->forge->addUniqueKey(['parent_id', 'school_year'], 'uq_parent_policy_year');
        $this->forge->addKey('school_year');
        $this->forge->createTable('parent_policy_acceptances', true);

        $this->backfillExistingAcceptances();
    }

    public function down(): void
    {
        $this->forge->dropTable('parent_policy_acceptances', true);
    }

    private function backfillExistingAcceptances(): void
    {
        if (! $this->db->tableExists('users')) {
            return;
        }

        $schoolYear = $this->configuredSchoolYear();
        if ($schoolYear === null) {
            return;
        }

        $builder = $this->db->table('users u')
            ->select('u.id')
            ->where('u.accept_school_policy', 1);

        $hasUserType = $this->db->fieldExists('user_type', 'users');
        $hasRoleTables = $this->db->tableExists('user_roles') && $this->db->tableExists('roles');

        if ($hasUserType && $hasRoleTables) {
            $builder->groupStart()
                ->where('u.user_type', 'primary')
                ->orWhere(
                    'EXISTS (SELECT 1 FROM user_roles ur INNER JOIN roles r ON r.id = ur.role_id WHERE ur.user_id = u.id AND LOWER(r.name) = ' . $this->db->escape('parent') . ')',
                    null,
                    false
                )
                ->groupEnd();
        } elseif ($hasUserType) {
            $builder->where('u.user_type', 'primary');
        } elseif ($hasRoleTables) {
            $builder->where(
                'EXISTS (SELECT 1 FROM user_roles ur INNER JOIN roles r ON r.id = ur.role_id WHERE ur.user_id = u.id AND LOWER(r.name) = ' . $this->db->escape('parent') . ')',
                null,
                false
            );
        } else {
            return;
        }

        $rows = $builder->get()
            ->getResultArray();

        foreach ($rows as $row) {
            $parentId = (int) ($row['id'] ?? 0);
            if ($parentId <= 0) {
                continue;
            }

            $existing = $this->db->table('parent_policy_acceptances')
                ->where('parent_id', $parentId)
                ->where('school_year', $schoolYear)
                ->get(1)
                ->getRowArray();

            if ($existing !== null) {
                continue;
            }

            $this->db->table('parent_policy_acceptances')->insert([
                'parent_id' => $parentId,
                'school_year' => $schoolYear,
                'accepted_at' => date('Y-m-d H:i:s'),
                'source' => 'legacy_backfill',
                'created_at' => date('Y-m-d H:i:s'),
                'updated_at' => date('Y-m-d H:i:s'),
            ]);
        }
    }

    private function configuredSchoolYear(): ?string
    {
        if ($this->db->tableExists('school_years')) {
            $row = $this->db->table('school_years')
                ->select('name')
                ->where('status', 'active')
                ->orderBy('id', 'DESC')
                ->get(1)
                ->getRowArray();

            $name = trim((string) ($row['name'] ?? ''));
            if (preg_match('/^\d{4}-\d{4}$/', $name)) {
                return $name;
            }
        }

        if (! $this->db->tableExists('configuration')) {
            return null;
        }

        $row = $this->db->table('configuration')
            ->select('config_value')
            ->where('config_key', 'school_year')
            ->orderBy('id', 'DESC')
            ->get(1)
            ->getRowArray();

        $name = trim((string) ($row['config_value'] ?? ''));

        return preg_match('/^\d{4}-\d{4}$/', $name) ? $name : null;
    }
}