<?php

namespace App\Http\Controllers;

use App\Http\Requests\LambdaRequest;
use Illuminate\Http\Request;
use Illuminate\Support\Facades\Storage;

class PbsdoctoranalyticsReportController extends Controller
{
    private const PARTITION = 'rapport-pulmocare';

    private const REPORT_START = 'April 2026';

    private const METRIC_PBC = '1782472261-38d31258-0708-46f0-a65f-6e2511b18d8b';

    private const METRIC_TOTAL = '1782472577-483a9a7f-7c53-479e-a0cb-00d400d55f30';

    private const METRIC_PULMO_DPI_PMDI = '1782472485-f9f2099e-4b6e-43d8-9212-62022ac97f55';

    private const METRIC_PULMO_NEB = '1782472500-115764ec-d4eb-4c0f-b729-3ad7270159a6';

    private const METRIC_PULMO_G = '1782472518-1edbc500-ad25-40fd-b56f-dd21ce4f8be9';

    private const METRIC_PULMO_GROUP = '1782472533-60e26841-e935-4a9f-b0f3-f8a2f72ec1d4';

    private const METRIC_BUDASURE = '1782472550-ce2be779-d7c2-4558-b2d6-c7ab0f353ef8';

    private const METRIC_VILORESP_U = '1782472564-9d256aff-3f8f-440e-88c5-66f26e1b5e06';

    private const METRIC_PS_SHARE = '1782472596-4ab4486a-6f2f-48da-861b-a59b33167ad2';

    private const DEFAULT_BRAND = 'pulmosamrt_group';

    /** Brand filter options → actual-value metric IDs */
    private const BRANDS = [
        'pulmosamrt_group' => [
            'id' => self::METRIC_PULMO_GROUP,
            'label' => 'Pulmosamrt Group',
        ],
        'pulmosmart_dpi_pmdi' => [
            'id' => self::METRIC_PULMO_DPI_PMDI,
            'label' => 'Pulmosmart DPI & pMDI',
        ],
        'pulmosmart_neb' => [
            'id' => self::METRIC_PULMO_NEB,
            'label' => 'Pulmosmart Neb',
        ],
        'pulmosmart_g' => [
            'id' => self::METRIC_PULMO_G,
            'label' => 'Pulmosmart G',
        ],
        'budasure' => [
            'id' => self::METRIC_BUDASURE,
            'label' => 'Budasure',
        ],
        'viloresp_u' => [
            'id' => self::METRIC_VILORESP_U,
            'label' => 'Viloresp U',
        ],
    ];

    private const METRICS = [
        self::METRIC_PBC => 'PBC Amt',
        self::METRIC_TOTAL => 'Total (Actual Value)',
        self::METRIC_PULMO_DPI_PMDI => 'Pulmosmart DPI & pMDI (Actual Value)',
        self::METRIC_PULMO_NEB => 'Pulmosmart Neb (Actual Value)',
        self::METRIC_PULMO_G => 'Pulmosmart G (Actual Value)',
        self::METRIC_PULMO_GROUP => 'Pulmosamrt Group (Actual Value)',
        self::METRIC_BUDASURE => 'Budasure (Actual Value)',
        self::METRIC_VILORESP_U => 'Viloresp U (Actual Value)',
        self::METRIC_PS_SHARE => '% PS Share',
    ];

    private ?string $accessToken = null;

    private ?object $tokenUser = null;

    public function __construct()
    {
        $this->_service = 'reports';
        $this->_module = 'pbs_doctor_analytics';
        $this->_viewname = 'pbsdoctoranalyticsreport';
        $this->_title = 'PBC Doctor Analytics';
        $this->_base_url = '/pbsdoctoranalyticsreport';
    }

    public function list(Request $request)
    {
        $this->bootstrapTokenSession($request);
        if ($request->hasSession()) {
            $request->session()->save();
        }

        return redirect($this->buildUrl('/report', $request));
    }

    public function report(Request $request)
    {
        $this->bootstrapTokenSession($request);
        $token = $this->assertPulmocareAccess($request);
        if ($request->hasSession()) {
            $request->session()->save();
        }

        $payload = $this->buildReportPayload($request);
        $response = LambdaRequest::getrequest(
            $this->_service,
            $this->_module . '/doctor_units',
            $payload,
            $token,
            300
        );

        $reportError = $this->resolveReportError($response);
        if ($reportError !== null) {
            if ($this->isAuthReportError($reportError)) {
                $this->forgetPersistedToken($request);
                abort(401, $reportError);
            }

            abort(502, $reportError);
        }

        $report = $response->data ?? (object) [];
        $allDataAccess = $this->hasAllDataAccess($this->tokenUser);
        $hierarchies = $allDataAccess ? $this->loadHierarchyOptions($token) : [];

        $brands = [];
        foreach (self::BRANDS as $key => $brand) {
            $brands[] = [
                'key' => $key,
                'id' => $brand['id'],
                'label' => $brand['label'],
            ];
        }

        return $this->view('report')->with([
            'title' => $this->_title,
            'base_url' => $this->_base_url,
            'token' => $token,
            'allDataAccess' => $allDataAccess,
            'hierarchies' => $hierarchies,
            'months' => $report->months ?? [],
            'metrics' => $report->metrics ?? [],
            'doctors' => $report->doctors ?? [],
            'data' => $report->data ?? (object) [],
            'brands' => $brands,
            'defaultBrand' => self::DEFAULT_BRAND,
            'metricIds' => [
                'pbc' => self::METRIC_PBC,
                'total' => self::METRIC_TOTAL,
                'pulmo' => self::METRIC_PULMO_GROUP,
                'pct' => self::METRIC_PS_SHARE,
            ],
        ]);
    }

    protected function buildReportPayload(Request $request): array
    {
        $metricLabels = [];
        foreach (self::METRICS as $id => $label) {
            $metricLabels[$id] = $label;
        }

        $startMonth = trim((string) $request->query('start_month', self::REPORT_START));
        if ($startMonth === '') {
            $startMonth = self::REPORT_START;
        }

        $payload = [
            'partition' => self::PARTITION,
            'metric_ids' => json_encode(array_keys(self::METRICS)),
            'metric_labels' => json_encode($metricLabels),
            'start_month' => $startMonth,
            'all' => '1',
        ];

        $hierarchyIds = $request->query('hierarchy_ids');
        if ($hierarchyIds !== null && $hierarchyIds !== '') {
            $payload['hierarchy_ids'] = is_array($hierarchyIds)
                ? json_encode(array_values($hierarchyIds))
                : (string) $hierarchyIds;
        }

        return $payload;
    }

    protected function hasAllDataAccess(?object $user): bool
    {
        if (!$user) {
            return false;
        }

        $flag = $user->all_data_access ?? null;

        return $flag === true
            || $flag === 1
            || $flag === '1'
            || (is_string($flag) && strtolower($flag) === 'true');
    }

    protected function loadHierarchyOptions(string $token): array
    {
        $response = LambdaRequest::getrequest(
            'ums',
            'hierarchy/hierarchy_below_me',
            [
                'partition' => self::PARTITION,
                'hierarchy_id' => 'root',
            ],
            $token
        );

        if (!is_object($response) || !isset($response->data->hierarchies)) {
            return [];
        }

        $hierarchies = $response->data->hierarchies;
        if (!is_array($hierarchies)) {
            return [];
        }

        return array_values(array_filter($hierarchies, function ($hierarchy) {
            return is_object($hierarchy) && !empty($hierarchy->id);
        }));
    }

    protected function assertPulmocareAccess(Request $request): string
    {
        $token = $this->resolveAccessToken($request);
        if (!$token) {
            if ($request->filled('token')) {
                abort(403, 'Invalid or truncated access token. Please open the full link from the app.');
            }

            abort(401, 'Access token is required. Open this report with ?token=... from the app.');
        }

        $payload = $this->decodeTokenPayload($token);
        $user = is_object($payload) ? ($payload->user ?? null) : null;
        if (!$user || !$this->isPulmocareUser($user)) {
            abort(403, 'Access denied. A valid pulmocare token is required.');
        }

        if ($this->isTokenPayloadExpired($payload)) {
            $this->forgetPersistedToken($request);
            abort(401, 'Your access token has expired. Please open a fresh link from the app.');
        }

        $this->accessToken = $token;
        $this->tokenUser = $user;

        return $token;
    }

    protected function bootstrapTokenSession(Request $request): void
    {
        $token = $this->extractRequestToken($request);
        if ($token === '') {
            return;
        }

        $user = $this->getUserFromToken($token);
        if ($user && $this->isPulmocareUser($user)) {
            $payload = $this->decodeTokenPayload($token);
            if (!$this->isTokenPayloadExpired($payload)) {
                $this->persistAccessToken($request, $token);
            }
        }
    }

    protected function isPulmocareUser(object $user): bool
    {
        return ($user->domain ?? '') === 'pulmocare'
            || str_starts_with((string) ($user->partition ?? ''), self::PARTITION);
    }

    protected function normalizeRawToken(string $token): string
    {
        $token = trim($token);
        if (stripos($token, 'Bearer ') === 0) {
            $token = trim(substr($token, 7));
        }

        return $token;
    }

    protected function resolveAccessToken(Request $request): ?string
    {
        $fromRequest = $this->extractRequestToken($request);

        if ($fromRequest !== '') {
            $payload = $this->decodeTokenPayload($fromRequest);
            $user = is_object($payload) ? ($payload->user ?? null) : null;
            if ($user && $this->isPulmocareUser($user) && !$this->isTokenPayloadExpired($payload)) {
                $this->persistAccessToken($request, $fromRequest);

                return $fromRequest;
            }
        }

        $storedToken = $this->loadPersistedToken($request);
        if ($storedToken !== '') {
            $payload = $this->decodeTokenPayload($storedToken);
            $user = is_object($payload) ? ($payload->user ?? null) : null;
            if ($user && $this->isPulmocareUser($user) && !$this->isTokenPayloadExpired($payload)) {
                return $storedToken;
            }

            $this->forgetPersistedToken($request);
        }

        return null;
    }

    protected function extractRequestToken(Request $request): string
    {
        $raw = $request->query('token', $request->input('token'));
        if ($raw === null || $raw === '') {
            $raw = $request->header('Authorization') ?? '';
        }

        return $this->normalizeRawToken((string) $raw);
    }

    protected function persistAccessToken(Request $request, string $token): void
    {
        $request->session()->put('pbs_doctor_analytics_report_token', $token);
        $this->tokenStorage()->put($this->tokenStoragePath($request), $token);
    }

    protected function loadPersistedToken(Request $request): string
    {
        if ($request->session()->has('pbs_doctor_analytics_report_token')) {
            $sessionToken = $this->normalizeRawToken((string) $request->session()->get('pbs_doctor_analytics_report_token'));
            if ($sessionToken !== '') {
                return $sessionToken;
            }
        }

        $path = $this->tokenStoragePath($request);
        if ($this->tokenStorage()->exists($path)) {
            return $this->normalizeRawToken((string) $this->tokenStorage()->get($path));
        }

        return '';
    }

    protected function forgetPersistedToken(Request $request): void
    {
        $request->session()->forget('pbs_doctor_analytics_report_token');
        $path = $this->tokenStoragePath($request);
        if ($this->tokenStorage()->exists($path)) {
            $this->tokenStorage()->delete($path);
        }
    }

    protected function tokenStoragePath(Request $request): string
    {
        return 'pbs_doctor_analytics_report_tokens/' . hash('sha256', $request->session()->getId());
    }

    protected function tokenStorage()
    {
        return Storage::disk('local');
    }

    protected function getUserFromToken(string $token): ?object
    {
        $payload = $this->decodeTokenPayload($token);
        if (!is_object($payload)) {
            return null;
        }

        return $payload->user ?? null;
    }

    protected function decodeTokenPayload(string $token): ?object
    {
        $token = $this->normalizeRawToken($token);
        $parts = explode('.', $token);
        if (count($parts) < 2) {
            return null;
        }

        $payloadSegment = strtr($parts[1], '-_', '+/');
        $padding = strlen($payloadSegment) % 4;
        if ($padding > 0) {
            $payloadSegment .= str_repeat('=', 4 - $padding);
        }

        $payload = json_decode(base64_decode($payloadSegment));

        return is_object($payload) ? $payload : null;
    }

    protected function isTokenPayloadExpired(?object $payload): bool
    {
        if (!is_object($payload) || !isset($payload->exp)) {
            return false;
        }

        return (int) $payload->exp < time();
    }

    protected function resolveReportError($response): ?string
    {
        if (!is_object($response)) {
            return 'Report service returned an invalid response.';
        }

        $status = strtolower((string) ($response->status ?? ''));
        $statusCode = (int) ($response->statusCode ?? 0);
        if ($status !== 'failed' && ($statusCode === 0 || $statusCode < 400)) {
            return null;
        }

        $message = trim((string) ($response->message ?? ''));
        if ($message === '') {
            $message = 'Failed to load report data.';
        }

        if ($this->isAuthReportError($message) || $statusCode === 401 || $statusCode === 403) {
            return 'Your access token has expired or is invalid. Please open a fresh link from the app.';
        }

        return $message;
    }

    protected function isAuthReportError(string $message): bool
    {
        $normalized = strtolower($message);

        return str_contains($normalized, 'unauthorized')
            || str_contains($normalized, 'expired')
            || str_contains($normalized, 'invalid token');
    }

    protected function buildUrl(string $path, Request $request): string
    {
        $query = array_filter([
            'start_month' => $request->query('start_month'),
        ], function ($value) {
            return $value !== null && $value !== '';
        });

        $token = $this->extractRequestToken($request);
        if ($token === '') {
            $token = $this->loadPersistedToken($request);
        }
        if ($token !== '') {
            $query['token'] = $token;
        }

        $url = $this->_base_url . $path;
        if (!empty($query)) {
            $url .= '?' . http_build_query($query);
        }

        return $url;
    }
}