/**
 * @node ocr-upload
 * @name OCR Upload
 * @category ocr
 * @version 1.3.0
 * @description Upload a file for OCR processing via pdftoimageapi
 * @icon file-scan
 */

const configSchema = {
    type: 'object',
    properties: {
        fileSource: {
            type: 'string',
            title: 'File Source',
            description: 'Path to file data (e.g., {{item.attachments[0]}} for loop iterations, or {{data.attachments[0]}} for direct input). Leave empty to auto-detect from input.'
        },
        baseUrl: {
            type: 'string',
            title: 'API Base URL',
            default: 'http://localhost:3000',
            description: 'Base URL of the OCR API'
        },
        credentialId: {
            type: 'string',
            title: 'Credential',
            description: 'Bearer or API Key credential for authentication',
            dynamicOptions: {
                source: 'credentials',
                filter: { type: 'api_key' }
            }
        },
        processingMode: {
            type: 'string',
            title: 'Processing Mode',
            enum: ['auto', 'single', 'batch', 'smart'],
            default: 'auto',
            description: 'How to process the uploaded file'
        },
        batchSize: {
            type: 'number',
            title: 'Batch Size',
            default: 5,
            description: 'Number of pages per batch (for batch mode)'
        },
        targetWidth: {
            type: 'number',
            title: 'Target Width',
            description: 'Target width in pixels for image conversion'
        },
        groupId: {
            type: 'string',
            title: 'Group ID',
            description: 'Optional group ID to associate jobs'
        }
    },
    required: ['baseUrl']
};

const inputSchema = {
    type: 'object',
    properties: {
        file: {
            type: 'object',
            description: 'Binary file object with type, data (base64), mimeType, filename, size'
        },
        storage: {
            type: 'object',
            description: 'Storage reference to retrieve file from database',
            properties: {
                collection: { type: 'string' },
                id: { type: 'string' }
            }
        }
    }
};

const outputSchema = {
    type: 'object',
    properties: {
        job: {
            type: 'object',
            properties: {
                id: { type: 'string' },
                status: { type: 'string' },
                filename: { type: 'string' },
                created_at: { type: 'string' }
            }
        }
    }
};

const outputs = [
    { name: 'main', displayName: 'Job Created', type: 'object', color: '#10b981' }
];

function isBinaryInput(input) {
    // Binary input can have either data (base64) or filePath (disk reference)
    return input && input.type === 'binary' && (typeof input.data === 'string' || typeof input.filePath === 'string');
}

function resolveBinaryData(file) {
    // If file has filePath, read from disk
    if (file.filePath && !file.data) {
        const readResult = smartbotic.fs.readFile(file.filePath, 'base64');
        if (readResult.success) {
            file.data = readResult.data;
            smartbotic.log.info(`Loaded binary from disk: ${file.filePath}`);
        } else {
            throw new Error(`Failed to read file from disk: ${file.filePath} - ${readResult.error}`);
        }
    }
    return file;
}

module.exports = {
    configSchema,
    inputSchema,
    outputSchema,
    outputs,

    async execute(config, input, context) {
        const baseUrl = (config.baseUrl || 'http://localhost:3000').replace(/\/$/, '');
        let file = null;

        // First priority: use configured fileSource if provided
        // The expression (e.g., {{item.attachments[0]}}) is evaluated by the workflow engine,
        // so config.fileSource contains the actual file object
        if (config.fileSource && typeof config.fileSource === 'object') {
            if (isBinaryInput(config.fileSource)) {
                file = config.fileSource;
                smartbotic.log.info('OCR Upload: Using configured file source');
            } else if (Array.isArray(config.fileSource) && config.fileSource.length > 0) {
                // If fileSource resolved to an array (e.g., attachments array), use first item
                file = config.fileSource[0];
                smartbotic.log.info(`OCR Upload: Using first item from configured file source array: ${file.filename}`);
            }
        }

        // Fallback: auto-detect from various input formats
        if (!file) {
            if (isBinaryInput(input.file)) {
                file = input.file;
            } else if (isBinaryInput(input)) {
                file = input;
            } else if (input.data && isBinaryInput(input.data)) {
                // Handle data wrapper from upstream nodes
                file = input.data;
            } else if (input.attachments && Array.isArray(input.attachments) && input.attachments.length > 0) {
                // Handle output from IMAP Extract Attachments - use first attachment
                file = input.attachments[0];
                smartbotic.log.info(`Using first attachment from array: ${file.filename}`);
            } else if (input.storage && input.storage.collection && input.storage.id) {
                // Load from storage database (metadata with filePath)
                const storageResult = smartbotic.storage.get(input.storage.collection, input.storage.id);
                if (!storageResult.found) {
                    throw new Error(`File not found in storage: ${input.storage.collection}/${input.storage.id}`);
                }
                const doc = storageResult.document;
                file = {
                    type: 'binary',
                    filePath: doc.filePath,  // Reference to disk location
                    mimeType: doc.mimeType,
                    filename: doc.filename,
                    size: doc.size
                };
            }
        }

        if (!file) {
            // Log available input keys for debugging
            const inputKeys = Object.keys(input || {}).join(', ');
            smartbotic.log.warn(`OCR Upload: No binary file found. Input keys: ${inputKeys}`);
            throw new Error('No file provided. Configure the "File Source" field with an expression like {{item.attachments[0]}} for loop iterations, or connect to IMAP Extract Attachments.');
        }

        // Resolve file data from disk if needed
        file = resolveBinaryData(file);

        const headers = {};

        if (config.credentialId) {
            const auth = smartbotic.credentials.get(config.credentialId);
            if (!auth.success) {
                throw new Error(`Failed to load credential: ${auth.error}`);
            }
            headers[auth.headerName] = auth.headerValue;
        }

        smartbotic.log.info(`OCR Upload: ${file.filename} (${file.size} bytes, type: ${file.mimeType})`);

        // Build form data for additional parameters
        const formData = {};
        if (config.processingMode && config.processingMode !== 'auto') {
            formData.processing_mode = config.processingMode;
        }
        if (config.batchSize) {
            formData.batch_size = String(config.batchSize);
        }
        if (config.targetWidth) {
            formData.target_width = String(config.targetWidth);
        }
        if (config.groupId) {
            formData.group_id = config.groupId;
        }

        // Use the new multipart file upload support with proper binary encoding
        const response = smartbotic.http.request({
            method: 'POST',
            url: `${baseUrl}/api/ocr/upload`,
            headers: headers,
            files: [{
                name: 'file',
                filename: file.filename,
                mimeType: file.mimeType,
                data: file.data  // base64 encoded - will be decoded to binary by http.request
            }],
            formData: formData,
            timeout: 120000
        });

        if (response.status < 200 || response.status >= 300) {
            const errorMsg = typeof response.data === 'string' ? response.data : JSON.stringify(response.data);
            if (response.status === 401 && !config.credentialId) { throw new Error('Authentication required - please select a credential in node settings'); } throw new Error(`OCR API error (${response.status}): ${errorMsg}`);
        }

        const data = typeof response.data === 'string' ? JSON.parse(response.data) : response.data;

        return {
            job: data.job || data
        };
    }
};