-- Bygma Prisbog Database Schema - Final Version
-- Perfectly aligned with actual CSV structure
-- CSV columns: Varegrp;VareNr;Tekst;Enhed;BruttoPris;Opdat;Nettopris;DB-nr;EAN-nr;Std

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_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 - exactly matching CSV structure
CREATE TABLE bygma_products (
    id INT PRIMARY KEY AUTO_INCREMENT,
    
    -- Exact CSV columns
    varegrp VARCHAR(10),          -- CSV: Varegrp
    vareNr VARCHAR(50) NOT NULL,  -- CSV: VareNr (unique identifier)
    tekst TEXT,                   -- CSV: Tekst
    enhed VARCHAR(20),            -- CSV: Enhed
    db_nr VARCHAR(50),            -- CSV: DB-nr
    ean_nr VARCHAR(50),           -- CSV: EAN-nr
    std VARCHAR(50),              -- CSV: Std
    
    -- Current pricing (from most recent import)
    current_brutto_pris DECIMAL(15,2),  -- CSV: BruttoPris
    current_netto_pris DECIMAL(15,2),   -- CSV: Nettopris
    current_opdat TINYINT,               -- CSV: Opdat
    
    -- 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,
    
    -- Indexes for performance
    UNIQUE KEY idx_vareNr (vareNr),
    INDEX idx_varegrp (varegrp),
    INDEX idx_tekst (tekst(100)),
    INDEX idx_current_prices (current_brutto_pris, current_netto_pris),
    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,
    
    -- Exact price fields from CSV
    brutto_pris DECIMAL(15,2),    -- CSV: BruttoPris
    netto_pris DECIMAL(15,2),     -- CSV: Nettopris
    opdat TINYINT,                -- CSV: Opdat
    
    -- Price change tracking
    price_change_pct DECIMAL(8,4) DEFAULT 0,
    is_current BOOLEAN DEFAULT TRUE,
    
    -- Import metadata
    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 (brutto_pris, netto_pris)
);

-- Import log to track all imports
CREATE TABLE bygma_import_log (
    id INT PRIMARY KEY AUTO_INCREMENT,
    import_batch_id VARCHAR(100) NOT NULL UNIQUE,
    filename VARCHAR(500),
    filepath VARCHAR(500),
    file_hash VARCHAR(64),
    file_size BIGINT,
    
    -- Import statistics
    total_rows INT DEFAULT 0,
    processed_rows INT DEFAULT 0,
    successful_rows INT DEFAULT 0,
    failed_rows INT DEFAULT 0,
    new_products INT DEFAULT 0,
    updated_products INT DEFAULT 0,
    updated_prices INT DEFAULT 0,
    
    -- Status tracking
    status ENUM('pending', 'processing', 'completed', 'failed') DEFAULT 'pending',
    error_summary TEXT,
    warnings TEXT,
    
    -- Timing
    started_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
    completed_at TIMESTAMP NULL,
    duration_seconds INT,
    
    -- User tracking
    imported_by VARCHAR(100),
    
    INDEX idx_batch_id (import_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, -- Can be NULL if not mapped yet
    
    -- Mapping metadata
    mapping_type ENUM('auto', 'manual', 'ai_suggested') DEFAULT 'auto',
    mapping_confidence DECIMAL(5,4), -- 0.0 to 1.0
    auto_update_price BOOLEAN DEFAULT FALSE,
    price_markup_pct DECIMAL(8,4) DEFAULT 0, -- Markup percentage
    
    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),
    
    -- Ensure only one mapping per Bygma product
    UNIQUE KEY unique_bygma_mapping (bygma_product_id)
);

-- Simplified Triggers (without recursive calls)

DELIMITER //

-- Trigger: Update last_seen and current prices 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_brutto_pris = NEW.brutto_pris,
        current_netto_pris = NEW.netto_pris,
        current_opdat = NEW.opdat,
        updated_at = CURRENT_TIMESTAMP
    WHERE id = NEW.product_id;
END//

-- Trigger: Calculate price change percentage and mark previous prices as not current
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 netto_pris 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.netto_pris - 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_brutto_pris,
    p.current_netto_pris,
    p.current_opdat,
    p.last_seen,
    pg.group_name,
    mm.material_id as mapped_material_id,
    mm.mapping_type,
    mm.auto_update_price,
    mm.price_markup_pct
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.brutto_pris,
    ph.netto_pris,
    ph.opdat,
    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.import_batch_id,
    il.filename,
    il.total_rows,
    il.processed_rows,
    il.successful_rows,
    il.failed_rows,
    il.new_products,
    il.updated_products,
    il.updated_prices,
    il.status,
    il.started_at,
    il.completed_at,
    il.duration_seconds,
    il.imported_by,
    ROUND((il.successful_rows / NULLIF(il.total_rows, 0)) * 100, 2) as success_rate_pct
FROM bygma_import_log il
ORDER BY il.started_at DESC;

-- Add some basic product groups based on common Bygma categories
INSERT INTO bygma_product_groups (varegrp, group_name) VALUES
('1000', 'Tømmer og planker'),
('3310', 'Porebeton og isolering'),
('3320', 'Leca og letbeton'),
('3330', 'Mursten og blokke'),
('2000', 'Plader og isolering'),
('4000', 'Tagmaterialer'),
('5000', 'Vinduer og døre'),
('6000', 'Beton og cement'),
('7000', 'Værktøj'),
('8000', 'Beslag og fittings'),
('9000', 'Diverse byggematerialer')
ON DUPLICATE KEY UPDATE group_name = VALUES(group_name);