-- Bygma Prisbog Database Schema (Fixed Version)
-- This creates tables for monthly Bygma price imports
-- Separate from the vendor history system

USE tilbudgivern;

-- Drop existing triggers first to avoid conflicts
DROP TRIGGER IF EXISTS tr_bygma_products_update_last_seen;
DROP TRIGGER IF EXISTS tr_bygma_price_history_deactivate_old;
DROP TRIGGER IF EXISTS tr_bygma_price_history_calculate_change;

-- Drop existing tables in correct order to avoid foreign key constraints
DROP TABLE IF EXISTS bygma_materials_mapping;
DROP TABLE IF EXISTS bygma_price_history;
DROP TABLE IF EXISTS bygma_import_log;
DROP TABLE IF EXISTS bygma_product_groups;
DROP TABLE IF EXISTS bygma_products;

-- Main table for Bygma products from monthly prisbog
CREATE TABLE bygma_products (
    id INT PRIMARY KEY AUTO_INCREMENT,
    vareNr VARCHAR(50) NOT NULL UNIQUE,
    tekst TEXT,
    enhed VARCHAR(20),
    varegrp VARCHAR(10),
    db_nr VARCHAR(50),
    ean_nr VARCHAR(50),
    std VARCHAR(50),
    
    -- Current pricing (for quick access)
    current_gross_price DECIMAL(15,2),
    current_net_price DECIMAL(15,2),
    
    -- Metadata
    first_seen DATE,
    last_seen DATE,
    is_active BOOLEAN DEFAULT TRUE,
    
    created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
    updated_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
    
    INDEX idx_vareNr (vareNr),
    INDEX idx_varegrp (varegrp),
    INDEX idx_tekst (tekst(100)),
    INDEX idx_current_prices (current_gross_price, current_net_price),
    INDEX idx_active (is_active),
    INDEX idx_last_seen (last_seen)
);

-- Product groups for categorization
CREATE TABLE bygma_product_groups (
    id INT PRIMARY KEY AUTO_INCREMENT,
    varegrp VARCHAR(10) NOT NULL UNIQUE,
    group_name VARCHAR(255),
    description TEXT,
    
    created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
    updated_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
    
    INDEX idx_varegrp (varegrp)
);

-- Price history to track all price changes over time
CREATE TABLE bygma_price_history (
    id INT PRIMARY KEY AUTO_INCREMENT,
    product_id INT NOT NULL,
    
    gross_price DECIMAL(15,2),
    net_price DECIMAL(15,2),
    
    -- Price change tracking
    price_change_pct DECIMAL(8,4) DEFAULT 0,
    is_current BOOLEAN DEFAULT TRUE,
    
    -- Import metadata
    update_flag TINYINT DEFAULT 0,
    import_date DATE,
    import_file VARCHAR(500),
    import_batch_id VARCHAR(100),
    
    created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
    
    FOREIGN KEY (product_id) REFERENCES bygma_products(id) ON DELETE CASCADE,
    
    INDEX idx_product (product_id),
    INDEX idx_import_batch (import_batch_id),
    INDEX idx_import_date (import_date),
    INDEX idx_current (is_current),
    INDEX idx_prices (gross_price, net_price)
);

-- Import log to track all imports
CREATE TABLE bygma_import_log (
    id INT PRIMARY KEY AUTO_INCREMENT,
    batch_id VARCHAR(100) NOT NULL UNIQUE,
    filename VARCHAR(500),
    file_hash VARCHAR(64),
    
    -- Import statistics
    total_rows INT DEFAULT 0,
    processed_rows INT DEFAULT 0,
    new_products INT DEFAULT 0,
    updated_products INT DEFAULT 0,
    errors INT DEFAULT 0,
    
    -- Status tracking
    status ENUM('pending', 'processing', 'completed', 'failed') DEFAULT 'pending',
    error_message TEXT,
    
    -- Timing
    started_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
    completed_at TIMESTAMP NULL,
    processing_time INT, -- seconds
    
    INDEX idx_batch_id (batch_id),
    INDEX idx_status (status),
    INDEX idx_started_at (started_at),
    INDEX idx_filename (filename(100))
);

-- Mapping table to connect Bygma products with existing materials
CREATE TABLE bygma_materials_mapping (
    id INT PRIMARY KEY AUTO_INCREMENT,
    bygma_product_id INT NOT NULL,
    material_id INT, -- Kan være NULL hvis ikke mappet endnu
    
    -- Mapping metadata
    mapping_type ENUM('auto', 'manual', 'ai_suggested') DEFAULT 'auto',
    mapping_confidence DECIMAL(5,4), -- 0.0 til 1.0
    auto_update_price BOOLEAN DEFAULT FALSE,
    
    created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
    updated_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
    mapped_by VARCHAR(100),
    
    FOREIGN KEY (bygma_product_id) REFERENCES bygma_products(id) ON DELETE CASCADE,
    
    INDEX idx_bygma_product (bygma_product_id),
    INDEX idx_material (material_id),
    INDEX idx_mapping_type (mapping_type),
    INDEX idx_auto_update (auto_update_price),
    
    -- Sikr kun én mapping per Bygma produkt
    UNIQUE KEY unique_bygma_mapping (bygma_product_id)
);

-- Simplified Triggers (without recursive calls)

DELIMITER //

-- Trigger: Update last_seen when new price comes in
CREATE TRIGGER tr_bygma_products_update_last_seen
AFTER INSERT ON bygma_price_history
FOR EACH ROW
BEGIN
    UPDATE bygma_products 
    SET last_seen = NEW.import_date,
        current_gross_price = NEW.gross_price,
        current_net_price = NEW.net_price,
        updated_at = CURRENT_TIMESTAMP
    WHERE id = NEW.product_id;
END//

-- Trigger: Calculate price change percentage
CREATE TRIGGER tr_bygma_price_history_calculate_change
BEFORE INSERT ON bygma_price_history
FOR EACH ROW
BEGIN
    DECLARE prev_price DECIMAL(15,2);
    
    -- Find previous price
    SELECT net_price INTO prev_price
    FROM bygma_price_history 
    WHERE product_id = NEW.product_id 
    AND is_current = TRUE 
    ORDER BY created_at DESC
    LIMIT 1;
    
    -- Calculate change if there's a previous price
    IF prev_price IS NOT NULL AND prev_price > 0 THEN
        SET NEW.price_change_pct = ((NEW.net_price - prev_price) / prev_price) * 100;
    END IF;
    
    -- Mark all other prices for this product as not current
    UPDATE bygma_price_history 
    SET is_current = FALSE 
    WHERE product_id = NEW.product_id;
END//

DELIMITER ;

-- Useful views for reporting and analysis

-- View: Current prices with product details
CREATE VIEW v_bygma_current_prices AS
SELECT 
    p.id,
    p.vareNr,
    p.tekst,
    p.enhed,
    p.varegrp,
    p.current_gross_price,
    p.current_net_price,
    p.last_seen,
    pg.group_name,
    mm.material_id as mapped_material_id,
    mm.mapping_type,
    mm.auto_update_price
FROM bygma_products p
LEFT JOIN bygma_product_groups pg ON p.varegrp = pg.varegrp
LEFT JOIN bygma_materials_mapping mm ON p.id = mm.bygma_product_id
WHERE p.is_active = TRUE;

-- View: Price history with changes
CREATE VIEW v_bygma_price_changes AS
SELECT 
    ph.id,
    p.vareNr,
    p.tekst,
    ph.gross_price,
    ph.net_price,
    ph.price_change_pct,
    ph.import_date,
    ph.import_file,
    ph.is_current
FROM bygma_price_history ph
JOIN bygma_products p ON ph.product_id = p.id
ORDER BY ph.import_date DESC, p.vareNr;

-- View: Import statistics
CREATE VIEW v_bygma_import_stats AS
SELECT 
    il.id,
    il.batch_id,
    il.filename,
    il.total_rows,
    il.processed_rows,
    il.new_products,
    il.updated_products,
    il.errors,
    il.status,
    il.started_at,
    il.completed_at,
    il.processing_time,
    ROUND((il.processed_rows / il.total_rows) * 100, 2) as success_rate_pct
FROM bygma_import_log il
ORDER BY il.started_at DESC;

-- Add some basic product groups
INSERT INTO bygma_product_groups (varegrp, group_name) VALUES
('3310', 'Porebeton og isolering'),
('3320', 'Leca og letbeton'),
('3330', 'Mursten og blokke')
ON DUPLICATE KEY UPDATE group_name = VALUES(group_name);

-- Grant necessary permissions to service user (run by admin separately if needed)
-- GRANT ALL PRIVILEGES ON tilbudgivern.bygma_* TO 'tilbudgivern_service'@'localhost';
-- GRANT SELECT ON tilbudgivern.v_bygma_* TO 'tilbudgivern_service'@'localhost';
-- FLUSH PRIVILEGES;