<?php
/**
 * Blocknotes JSON Storage Engine Functions
 */

/**
 * Ensure storage directory exists.
 */
function ensure_blocknotes_directory() {
    if (!is_dir(BLOCKNOTES_FOLD)) {
        @mkdir(BLOCKNOTES_FOLD, 0777, true);
    }
}

/**
 * Scan BLOCKNOTES_FOLD and load all JSON files.
 */
function get_all_blocknotes() {
    ensure_blocknotes_directory();
    $files = glob(BLOCKNOTES_FOLD . "*.json");
    $blocknotes = [];

    if ($files) {
        foreach ($files as $filepath) {
            $content = file_get_contents($filepath);
            $data = json_decode($content, true);
            if (is_array($data) && isset($data['id'])) {
                $blocknotes[] = $data;
            }
        }
    }
    
    // Sort by updated_at descending
    usort($blocknotes, function($a, $b) {
        return strtotime($b['updated_at'] ?? 0) - strtotime($a['updated_at'] ?? 0);
    });

    return $blocknotes;
}

/**
 * Get blocknotes assigned to a specific user (or all if admin).
 */
function get_user_blocknotes($username, $is_admin = false) {
    $all = get_all_blocknotes();
    if ($is_admin) {
        return $all;
    }

    return array_filter($all, function($bn) use ($username) {
        return isset($bn['username']) && strtolower($bn['username']) === strtolower($username);
    });
}

/**
 * Find blocknote by ID.
 */
function get_blocknote_by_id($id) {
    ensure_blocknotes_directory();
    $filename = BLOCKNOTES_FOLD . preg_replace('/[^a-zA-Z0-9_\-]/', '', $id) . ".json";

    if (file_exists($filename)) {
        $content = file_get_contents($filename);
        $data = json_decode($content, true);
        if (is_array($data)) return $data;
    }

    // Fallback search across all files if ID is stored inside
    $all = get_all_blocknotes();
    foreach ($all as $bn) {
        if (isset($bn['id']) && $bn['id'] === $id) {
            return $bn;
        }
    }
    return null;
}

/**
 * Save blocknote to JSON file.
 */
function save_blocknote($data) {
    ensure_blocknotes_directory();
    if (empty($data['id'])) {
        $data['id'] = 'bn_' . uniqid();
    }
    $data['updated_at'] = date('Y-m-d H:i:s');
    if (empty($data['created_at'])) {
        $data['created_at'] = $data['updated_at'];
    }
    if (!isset($data['notes'])) {
        $data['notes'] = [];
    }

    $filepath = BLOCKNOTES_FOLD . preg_replace('/[^a-zA-Z0-9_\-]/', '', $data['id']) . ".json";
    $json_string = json_encode($data, JSON_PRETTY_PRINT | JSON_UNESCAPED_UNICODE);
    
    return file_put_contents($filepath, $json_string) !== false;
}

/**
 * Create a new blocknote.
 */
function create_blocknote($title, $username) {
    $title = trim($title);
    if (empty($title)) {
        return ['success' => false, 'message' => 'Il titolo del blocknote è obbligatorio.'];
    }

    $id = 'bn_' . uniqid();
    $data = [
        'id' => $id,
        'title' => $title,
        'username' => $username,
        'created_at' => date('Y-m-d H:i:s'),
        'updated_at' => date('Y-m-d H:i:s'),
        'notes' => []
    ];

    if (save_blocknote($data)) {
        return ['success' => true, 'id' => $id, 'message' => 'Blocknote creato con successo!'];
    }
    return ['success' => false, 'message' => 'Errore nel salvataggio del file JSON.'];
}

/**
 * Import a JSON string (supports standard format and legacy codes format).
 */
function import_blocknote_json($json_string, $username, $custom_title = '') {
    $data = json_decode($json_string, true);
    if (!is_array($data)) {
        return ['success' => false, 'message' => 'File JSON non valido o malformato.'];
    }

    $id = 'bn_' . uniqid();
    $title = !empty($custom_title) ? trim($custom_title) : 'Blocknote Importato';

    // Case 1: Standard format with 'notes' array
    if (isset($data['notes']) && is_array($data['notes'])) {
        $bn = [
            'id' => $id,
            'title' => !empty($data['title']) ? $data['title'] : $title,
            'username' => $username,
            'created_at' => date('Y-m-d H:i:s'),
            'updated_at' => date('Y-m-d H:i:s'),
            'notes' => $data['notes']
        ];
        if (save_blocknote($bn)) {
            return ['success' => true, 'id' => $id, 'message' => 'Blocknote importato con successo!'];
        }
    }

    // Case 2: Legacy format (array of notes with 'title', 'description', 'codes')
    if (isset($data[0]) && is_array($data[0])) {
        $notes = [];
        foreach ($data as $n_idx => $legacy_note) {
            $note_id = 'note_' . ($n_idx + 1) . '_' . uniqid();
            $subnotes = [];

            if (isset($legacy_note['codes']) && is_array($legacy_note['codes'])) {
                foreach ($legacy_note['codes'] as $s_idx => $legacy_code) {
                    $subnotes[] = [
                        'id' => 'sub_' . ($s_idx + 1) . '_' . uniqid(),
                        'title' => $legacy_code['sub_title'] ?? 'Comando',
                        'type' => 'command',
                        'content' => $legacy_code['code'] ?? ''
                    ];
                }
            }

            $notes[] = [
                'id' => $note_id,
                'title' => $legacy_note['title'] ?? 'Nota ' . ($n_idx + 1),
                'description' => $legacy_note['description'] ?? '',
                'subnotes' => $subnotes
            ];
        }

        $bn = [
            'id' => $id,
            'title' => $title,
            'username' => $username,
            'created_at' => date('Y-m-d H:i:s'),
            'updated_at' => date('Y-m-d H:i:s'),
            'notes' => $notes
        ];

        if (save_blocknote($bn)) {
            return ['success' => true, 'id' => $id, 'message' => 'Blocknote in formato legacy importato e convertito con successo!'];
        }
    }

    return ['success' => false, 'message' => 'Formato JSON non riconosciuto.'];
}

/**
 * Check permission on blocknote.
 */
function can_access_blocknote($bn, $username, $is_admin) {
    if (!$bn) return false;
    if ($is_admin) return true;
    return strtolower($bn['username'] ?? '') === strtolower($username);
}

/**
 * Rename a blocknote.
 */
function rename_blocknote($id, $new_title, $username, $is_admin) {
    $bn = get_blocknote_by_id($id);
    if (!$bn) return ['success' => false, 'message' => 'Blocknote non trovato.'];
    if (!can_access_blocknote($bn, $username, $is_admin)) {
        return ['success' => false, 'message' => 'Non hai i permessi per modificare questo blocknote.'];
    }

    $new_title = trim($new_title);
    if (empty($new_title)) return ['success' => false, 'message' => 'Il titolo non può essere vuoto.'];

    $bn['title'] = $new_title;
    if (save_blocknote($bn)) {
        return ['success' => true, 'message' => 'Blocknote rinominato con successo.'];
    }
    return ['success' => false, 'message' => 'Errore nel salvataggio del file JSON.'];
}

/**
 * Delete a blocknote.
 */
function delete_blocknote($id, $username, $is_admin) {
    $bn = get_blocknote_by_id($id);
    if (!$bn) return ['success' => false, 'message' => 'Blocknote non trovato.'];
    if (!can_access_blocknote($bn, $username, $is_admin)) {
        return ['success' => false, 'message' => 'Non hai i permessi per eliminare questo blocknote.'];
    }

    $filepath = BLOCKNOTES_FOLD . preg_replace('/[^a-zA-Z0-9_\-]/', '', $bn['id']) . ".json";
    if (file_exists($filepath)) {
        @unlink($filepath);
    }
    return ['success' => true, 'message' => 'Blocknote eliminato con successo.'];
}

/**
 * Add a new Note block to a Blocknote.
 */
function add_note($blocknote_id, $title, $description, $username, $is_admin) {
    $bn = get_blocknote_by_id($blocknote_id);
    if (!$bn) return ['success' => false, 'message' => 'Blocknote non trovato.'];
    if (!can_access_blocknote($bn, $username, $is_admin)) return ['success' => false, 'message' => 'Permesso negato.'];

    $title = trim($title);
    if (empty($title)) return ['success' => false, 'message' => 'Il titolo della nota è obbligatorio.'];

    $note_id = 'note_' . uniqid();
    $new_note = [
        'id' => $note_id,
        'title' => $title,
        'description' => trim($description),
        'subnotes' => []
    ];

    $bn['notes'][] = $new_note;
    if (save_blocknote($bn)) {
        return ['success' => true, 'note_id' => $note_id, 'message' => 'Nota aggiunta con successo!'];
    }
    return ['success' => false, 'message' => 'Errore durante il salvataggio.'];
}

/**
 * Edit an existing Note block.
 */
function edit_note($blocknote_id, $note_id, $title, $description, $username, $is_admin) {
    $bn = get_blocknote_by_id($blocknote_id);
    if (!$bn) return ['success' => false, 'message' => 'Blocknote non trovato.'];
    if (!can_access_blocknote($bn, $username, $is_admin)) return ['success' => false, 'message' => 'Permesso negato.'];

    $title = trim($title);
    if (empty($title)) return ['success' => false, 'message' => 'Il titolo della nota è obbligatorio.'];

    $found = false;
    foreach ($bn['notes'] as &$note) {
        if ($note['id'] === $note_id) {
            $note['title'] = $title;
            $note['description'] = trim($description);
            $found = true;
            break;
        }
    }

    if (!$found) return ['success' => false, 'message' => 'Nota non trovata.'];

    if (save_blocknote($bn)) {
        return ['success' => true, 'message' => 'Nota modificata con successo!'];
    }
    return ['success' => false, 'message' => 'Errore nel salvataggio.'];
}

/**
 * Delete a Note block.
 */
function delete_note($blocknote_id, $note_id, $username, $is_admin) {
    $bn = get_blocknote_by_id($blocknote_id);
    if (!$bn) return ['success' => false, 'message' => 'Blocknote non trovato.'];
    if (!can_access_blocknote($bn, $username, $is_admin)) return ['success' => false, 'message' => 'Permesso negato.'];

    $initial_count = count($bn['notes']);
    $bn['notes'] = array_values(array_filter($bn['notes'], function($n) use ($note_id) {
        return $n['id'] !== $note_id;
    }));

    if (count($bn['notes']) === $initial_count) {
        return ['success' => false, 'message' => 'Nota non trovata.'];
    }

    if (save_blocknote($bn)) {
        return ['success' => true, 'message' => 'Nota eliminata con successo.'];
    }
    return ['success' => false, 'message' => 'Errore nel salvataggio.'];
}

/**
 * Add a Subnote to a Note block.
 */
function add_subnote($blocknote_id, $note_id, $sub_title, $type, $content, $username, $is_admin) {
    $bn = get_blocknote_by_id($blocknote_id);
    if (!$bn) return ['success' => false, 'message' => 'Blocknote non trovato.'];
    if (!can_access_blocknote($bn, $username, $is_admin)) return ['success' => false, 'message' => 'Permesso negato.'];

    $sub_title = trim($sub_title);
    if (empty($sub_title)) return ['success' => false, 'message' => 'Il titolo della sottonota è obbligatorio.'];

    $type = ($type === 'command') ? 'command' : 'text';
    $sub_id = 'sub_' . uniqid();

    $found = false;
    foreach ($bn['notes'] as &$note) {
        if ($note['id'] === $note_id) {
            if (!isset($note['subnotes'])) $note['subnotes'] = [];
            $note['subnotes'][] = [
                'id' => $sub_id,
                'title' => $sub_title,
                'type' => $type,
                'content' => $content
            ];
            $found = true;
            break;
        }
    }

    if (!$found) return ['success' => false, 'message' => 'Nota genitore non trovata.'];

    if (save_blocknote($bn)) {
        return ['success' => true, 'subnote_id' => $sub_id, 'message' => 'Sottonota aggiunta con successo!'];
    }
    return ['success' => false, 'message' => 'Errore nel salvataggio.'];
}

/**
 * Edit a Subnote.
 */
function edit_subnote($blocknote_id, $note_id, $sub_id, $sub_title, $type, $content, $username, $is_admin) {
    $bn = get_blocknote_by_id($blocknote_id);
    if (!$bn) return ['success' => false, 'message' => 'Blocknote non trovato.'];
    if (!can_access_blocknote($bn, $username, $is_admin)) return ['success' => false, 'message' => 'Permesso negato.'];

    $sub_title = trim($sub_title);
    if (empty($sub_title)) return ['success' => false, 'message' => 'Il titolo della sottonota è obbligatorio.'];
    $type = ($type === 'command') ? 'command' : 'text';

    $found = false;
    foreach ($bn['notes'] as &$note) {
        if ($note['id'] === $note_id) {
            if (isset($note['subnotes'])) {
                foreach ($note['subnotes'] as &$sub) {
                    if ($sub['id'] === $sub_id) {
                        $sub['title'] = $sub_title;
                        $sub['type'] = $type;
                        $sub['content'] = $content;
                        $found = true;
                        break 2;
                    }
                }
            }
        }
    }

    if (!$found) return ['success' => false, 'message' => 'Sottonota non trovata.'];

    if (save_blocknote($bn)) {
        return ['success' => true, 'message' => 'Sottonota modificata con successo!'];
    }
    return ['success' => false, 'message' => 'Errore nel salvataggio.'];
}

/**
 * Delete a Subnote.
 */
function delete_subnote($blocknote_id, $note_id, $sub_id, $username, $is_admin) {
    $bn = get_blocknote_by_id($blocknote_id);
    if (!$bn) return ['success' => false, 'message' => 'Blocknote non trovato.'];
    if (!can_access_blocknote($bn, $username, $is_admin)) return ['success' => false, 'message' => 'Permesso negato.'];

    $found = false;
    foreach ($bn['notes'] as &$note) {
        if ($note['id'] === $note_id && isset($note['subnotes'])) {
            $initial = count($note['subnotes']);
            $note['subnotes'] = array_values(array_filter($note['subnotes'], function($s) use ($sub_id) {
                return $s['id'] !== $sub_id;
            }));
            if (count($note['subnotes']) < $initial) {
                $found = true;
                break;
            }
        }
    }

    if (!$found) return ['success' => false, 'message' => 'Sottonota non trovata.'];

    if (save_blocknote($bn)) {
        return ['success' => true, 'message' => 'Sottonota eliminata con successo.'];
    }
    return ['success' => false, 'message' => 'Errore nel salvataggio.'];
}

/**
 * Compatibility Aliases
 */
function add_note_to_blocknote($blocknote_id, $title, $description, $username, $is_admin) {
    return add_note($blocknote_id, $title, $description, $username, $is_admin);
}

function edit_note_in_blocknote($blocknote_id, $note_id, $title, $description, $username, $is_admin) {
    return edit_note($blocknote_id, $note_id, $title, $description, $username, $is_admin);
}

function delete_note_from_blocknote($blocknote_id, $note_id, $username, $is_admin) {
    return delete_note($blocknote_id, $note_id, $username, $is_admin);
}

function add_subnote_to_note($blocknote_id, $note_id, $sub_title, $type, $content, $username, $is_admin) {
    return add_subnote($blocknote_id, $note_id, $sub_title, $type, $content, $username, $is_admin);
}

function edit_subnote_in_note($blocknote_id, $note_id, $sub_id, $sub_title, $type, $content, $username, $is_admin) {
    return edit_subnote($blocknote_id, $note_id, $sub_id, $sub_title, $type, $content, $username, $is_admin);
}

function delete_subnote_from_note($blocknote_id, $note_id, $sub_id, $username, $is_admin) {
    return delete_subnote($blocknote_id, $note_id, $sub_id, $username, $is_admin);
}