-- ======================================================
-- LIVESTOCK MARKETPLACE - COMPLETE PRODUCTION SCHEMA
-- ======================================================

-- 1. EXTENSIONS
-- ======================================================
CREATE EXTENSION IF NOT EXISTS "pgcrypto";
CREATE EXTENSION IF NOT EXISTS "uuid-ossp";
CREATE EXTENSION IF NOT EXISTS "postgis"; -- Crucial for "Near Me" filters

SET timezone TO 'UTC';

-- 2. GLOBAL FUNCTIONS (Timestamps)
-- ======================================================
CREATE OR REPLACE FUNCTION set_updated_at()
RETURNS TRIGGER AS $$
BEGIN
    NEW.updated_at = NOW();
    RETURN NEW;
END;
$$ LANGUAGE plpgsql;

-- 3. ENUM TYPES
-- ======================================================
DO $$
BEGIN
    IF NOT EXISTS (SELECT 1 FROM pg_type WHERE typname = 'sex_enum') THEN
        CREATE TYPE sex_enum AS ENUM ('M','F','Neutered');
    END IF;
    IF NOT EXISTS (SELECT 1 FROM pg_type WHERE typname = 'purpose_enum') THEN
        CREATE TYPE purpose_enum AS ENUM ('dairy','meat','breeding','pet','work','other');
    END IF;
    IF NOT EXISTS (SELECT 1 FROM pg_type WHERE typname = 'health_status_enum') THEN
        CREATE TYPE health_status_enum AS ENUM ('healthy','minor_issues','serious_issues');
    END IF;
    IF NOT EXISTS (SELECT 1 FROM pg_type WHERE typname = 'location_type_enum') THEN
        CREATE TYPE location_type_enum AS ENUM ('farm','home','office','temporary_gps','other_saved','other');
    END IF;
    IF NOT EXISTS (SELECT 1 FROM pg_type WHERE typname = 'source_type_enum') THEN
        CREATE TYPE source_type_enum AS ENUM ('gps','device_gps','manual','imported','unknown');
    END IF;
    IF NOT EXISTS (SELECT 1 FROM pg_type WHERE typname = 'listing_type_enum') THEN
        CREATE TYPE listing_type_enum AS ENUM ('sale','stud_service','adoption','other');
    END IF;
    IF NOT EXISTS (SELECT 1 FROM pg_type WHERE typname = 'listing_status_enum') THEN
        CREATE TYPE listing_status_enum AS ENUM ('active','sold','expired','hidden','deleted');
    END IF;
    IF NOT EXISTS (SELECT 1 FROM pg_type WHERE typname = 'seller_type_enum') THEN
        CREATE TYPE seller_type_enum AS ENUM ('owner','farmer','broker','agent','other');
    END IF;
    IF NOT EXISTS (SELECT 1 FROM pg_type WHERE typname = 'listing_role_enum') THEN
        CREATE TYPE listing_role_enum AS ENUM ('seller_buyer','service_provider');
    END IF;
    IF NOT EXISTS (SELECT 1 FROM pg_type WHERE typname = 'user_type_enum') THEN
        CREATE TYPE user_type_enum AS ENUM ('user','admin','moderator');
    END IF;
    IF NOT EXISTS (SELECT 1 FROM pg_type WHERE typname = 'message_type_enum') THEN
        CREATE TYPE message_type_enum AS ENUM ('text','media','both');
    END IF;
    IF NOT EXISTS (SELECT 1 FROM pg_type WHERE typname = 'media_type_enum') THEN
        CREATE TYPE media_type_enum AS ENUM ('image','video','audio','document');
    END IF;
    IF NOT EXISTS (SELECT 1 FROM pg_type WHERE typname = 'communication_type_enum') THEN
        CREATE TYPE communication_type_enum AS ENUM ('call','missed_call','voicemail');
    END IF;
    IF NOT EXISTS (SELECT 1 FROM pg_type WHERE typname = 'call_status_enum') THEN
        CREATE TYPE call_status_enum AS ENUM ('initiated','ringing','answered','completed','failed','busy','no_answer');
    END IF;
    IF NOT EXISTS (SELECT 1 FROM pg_type WHERE typname = 'pregnancy_status_enum') THEN
        CREATE TYPE pregnancy_status_enum AS ENUM ('none', 'pregnant', 'unknown');
    END IF;
    IF NOT EXISTS (SELECT 1 FROM pg_type WHERE typname = 'requirement_status_enum') THEN
        CREATE TYPE requirement_status_enum AS ENUM ('open', 'fulfilled', 'cancelled');
    END IF;
    IF NOT EXISTS (SELECT 1 FROM pg_type WHERE typname = 'analytics_event_type_enum') THEN
        CREATE TYPE analytics_event_type_enum AS ENUM ('views_count','bookmarks_count','enquiries_call_count','enquiries_whatsapp_count');
    END IF;
    IF NOT EXISTS (SELECT 1 FROM pg_type WHERE typname = 'listing_score_status_enum') THEN
        CREATE TYPE listing_score_status_enum AS ENUM ('pending', 'processing', 'completed', 'failed');
    END IF;
    IF NOT EXISTS (SELECT 1 FROM pg_type WHERE typname = 'source_confidence_enum') THEN
        CREATE TYPE source_confidence_enum AS ENUM ('high', 'medium', 'low', 'unknown');
    END IF;
END $$;

-- 4. USERS & AUTHENTICATION
-- ======================================================
CREATE TABLE subscription_plans (
    id UUID PRIMARY KEY DEFAULT gen_random_uuid(),
    name VARCHAR(100) NOT NULL UNIQUE,
    description TEXT,
    price NUMERIC(10, 2),
    currency VARCHAR(10) DEFAULT 'INR',
    duration_days INT, -- Validity in days
    features JSONB, -- Flexible JSON for features like {"max_listings": 10}
    is_active BOOLEAN DEFAULT TRUE,
    created_at TIMESTAMPTZ NOT NULL DEFAULT NOW(),
    updated_at TIMESTAMPTZ NOT NULL DEFAULT NOW()
);
CREATE TRIGGER trg_subscription_plans_updated_at BEFORE UPDATE ON subscription_plans FOR EACH ROW EXECUTE FUNCTION set_updated_at();

CREATE TABLE users (
    id UUID PRIMARY KEY DEFAULT gen_random_uuid(),
    phone_number VARCHAR(20) UNIQUE,
    name VARCHAR(255),
    avatar_url TEXT,
    language VARCHAR(10),
    timezone VARCHAR(50),
    is_active BOOLEAN NOT NULL DEFAULT TRUE,
    roles listing_role_enum[] NOT NULL DEFAULT '{seller_buyer}',
    active_role listing_role_enum NOT NULL DEFAULT 'seller_buyer',
    user_type user_type_enum NOT NULL DEFAULT 'user',
    country_code VARCHAR(10) NOT NULL DEFAULT '+91',
    
    -- Legacy role field (for backward compatibility with auth code)
    role listing_role_enum, -- Deprecated: use user_type for system roles, roles[] for marketplace roles
    
    -- Token version for global logout
    token_version INT NOT NULL DEFAULT 1,
    
    -- Seller Ratings (Cached for speed)
    rating_average NUMERIC(3, 2) DEFAULT 0.00,
    rating_count INT DEFAULT 0,

    -- Subscription Info
    subscription_plan_id UUID REFERENCES subscription_plans(id) ON DELETE SET NULL,
    subscription_expires_at TIMESTAMPTZ,

    deleted BOOLEAN NOT NULL DEFAULT FALSE,
    created_at TIMESTAMPTZ NOT NULL DEFAULT NOW(),
    updated_at TIMESTAMPTZ NOT NULL DEFAULT NOW(),
    last_login_at TIMESTAMPTZ NOT NULL DEFAULT NOW()
);
CREATE TRIGGER trg_users_updated_at BEFORE UPDATE ON users FOR EACH ROW EXECUTE FUNCTION set_updated_at();

CREATE TABLE otp_requests (
    id UUID PRIMARY KEY DEFAULT gen_random_uuid(),
    phone_number VARCHAR(20) NOT NULL,
    country_code VARCHAR(10) NOT NULL DEFAULT '+91',
    otp_hash VARCHAR(255) NOT NULL,
    deleted BOOLEAN NOT NULL DEFAULT FALSE,
    expires_at TIMESTAMPTZ NOT NULL,
    consumed_at TIMESTAMPTZ,
    attempt_count INT NOT NULL DEFAULT 0,
    created_at TIMESTAMPTZ NOT NULL DEFAULT NOW()
);
CREATE INDEX idx_otp_phone_unconsumed ON otp_requests (phone_number) WHERE consumed_at IS NULL;

CREATE TABLE user_devices (
    id UUID PRIMARY KEY DEFAULT gen_random_uuid(),
    user_id UUID NOT NULL REFERENCES users(id) ON DELETE CASCADE,
    device_identifier TEXT,
    device_platform TEXT NOT NULL,
    device_model TEXT,
    os_version TEXT,
    app_version TEXT,
    language_code TEXT,
    timezone TEXT,
    fcm_token TEXT, -- For Push Notifications
    lat NUMERIC(10,7),
    lng NUMERIC(10,7),
    first_seen_at TIMESTAMPTZ NOT NULL DEFAULT NOW(),
    last_seen_at TIMESTAMPTZ,
    is_active BOOLEAN NOT NULL DEFAULT TRUE,
    created_at TIMESTAMPTZ NOT NULL DEFAULT NOW(),
    updated_at TIMESTAMPTZ NOT NULL DEFAULT NOW(),
    UNIQUE(user_id, device_identifier)
);
CREATE INDEX idx_user_devices_user ON user_devices (user_id);
CREATE INDEX idx_user_devices_device_identifier ON user_devices (device_identifier);
CREATE INDEX idx_user_devices_platform ON user_devices (device_platform);
CREATE INDEX idx_user_devices_last_seen ON user_devices (last_seen_at);

CREATE TABLE refresh_tokens (
    id UUID PRIMARY KEY DEFAULT gen_random_uuid(),
    user_id UUID NOT NULL REFERENCES users(id) ON DELETE CASCADE,
    device_id VARCHAR(255) NOT NULL,
    token_id UUID NOT NULL UNIQUE,
    token_hash VARCHAR(255) NOT NULL,
    user_agent TEXT,
    ip_address VARCHAR(45),
    expires_at TIMESTAMPTZ NOT NULL,
    last_used_at TIMESTAMPTZ NOT NULL DEFAULT NOW(),
    revoked_at TIMESTAMPTZ,
    reuse_detected_at TIMESTAMPTZ,
    rotated_from_id UUID REFERENCES refresh_tokens(id) ON DELETE SET NULL,
    created_at TIMESTAMPTZ NOT NULL DEFAULT NOW()
);
CREATE INDEX idx_refresh_tokens_user_device ON refresh_tokens(user_id, device_id);
CREATE INDEX idx_refresh_tokens_expires ON refresh_tokens(expires_at);
CREATE INDEX idx_refresh_tokens_token_hash ON refresh_tokens(token_hash);
CREATE INDEX idx_refresh_tokens_revoked ON refresh_tokens(revoked_at);

-- Authentication Audit Logging (for security monitoring)
CREATE TABLE auth_audit (
    id UUID PRIMARY KEY DEFAULT gen_random_uuid(),
    user_id UUID REFERENCES users(id) ON DELETE SET NULL,
    action VARCHAR(100) NOT NULL,
    status VARCHAR(50) NOT NULL,
    risk_level VARCHAR(20) DEFAULT 'INFO',
    device_id VARCHAR(255),
    ip_address VARCHAR(45),
    user_agent TEXT,
    meta JSONB,
    created_at TIMESTAMPTZ NOT NULL DEFAULT NOW()
);
CREATE INDEX idx_auth_audit_user ON auth_audit(user_id);
CREATE INDEX idx_auth_audit_created ON auth_audit(created_at);
CREATE INDEX idx_auth_audit_action ON auth_audit(action);
CREATE INDEX idx_auth_audit_status ON auth_audit(status);
CREATE INDEX idx_auth_audit_risk_level ON auth_audit(risk_level);

-- 5. MASTER DATA (Species & Breeds)
-- ======================================================
CREATE TABLE species (
    id UUID PRIMARY KEY DEFAULT gen_random_uuid(),
    name VARCHAR(120) NOT NULL UNIQUE,
    deleted BOOLEAN NOT NULL DEFAULT FALSE,
    created_at TIMESTAMPTZ NOT NULL DEFAULT NOW(),
    updated_at TIMESTAMPTZ NOT NULL DEFAULT NOW()
);

CREATE TABLE breeds (
    id UUID PRIMARY KEY DEFAULT gen_random_uuid(),
    species_id UUID NOT NULL REFERENCES species(id) ON DELETE RESTRICT,
    name VARCHAR(150) NOT NULL,
    description TEXT,
    deleted BOOLEAN NOT NULL DEFAULT FALSE,
    created_at TIMESTAMPTZ NOT NULL DEFAULT NOW(),
    updated_at TIMESTAMPTZ NOT NULL DEFAULT NOW(),
    UNIQUE(species_id, name)
);

-- 6. LOCATIONS (Optimized with PostGIS)
-- ======================================================
CREATE TABLE locations (
    id UUID PRIMARY KEY DEFAULT gen_random_uuid(),
    user_id UUID REFERENCES users(id) ON DELETE CASCADE,
    lat NUMERIC(10,7),
    lng NUMERIC(10,7),
    
    -- AUTOMATIC GEOGRAPHY COLUMN (The Magic for 'Near Me' queries)
    -- This automatically creates a spatial point whenever you save lat/lng
    geog GEOGRAPHY(POINT, 4326) GENERATED ALWAYS AS (
        CASE WHEN lat IS NOT NULL AND lng IS NOT NULL 
        THEN ST_SetSRID(ST_MakePoint(lng, lat), 4326)::geography 
        ELSE NULL END
    ) STORED,

    is_saved_address BOOLEAN NOT NULL DEFAULT FALSE,
    location_type location_type_enum,
    country VARCHAR(100),
    state VARCHAR(100),
    district VARCHAR(100),
    city_village VARCHAR(150),
    pincode VARCHAR(20),

    source_type source_type_enum DEFAULT 'unknown',
    source_confidence source_confidence_enum DEFAULT 'unknown',
    selected_location BOOLEAN NOT NULL DEFAULT FALSE,
    deleted BOOLEAN NOT NULL DEFAULT FALSE,
    created_at TIMESTAMPTZ NOT NULL DEFAULT NOW(),
    updated_at TIMESTAMPTZ NOT NULL DEFAULT NOW()
);
CREATE INDEX idx_locations_geog ON locations USING GIST (geog); -- Spatial Index
CREATE INDEX idx_locations_user ON locations (user_id);
CREATE INDEX idx_locations_lat_lng ON locations (lat, lng);
CREATE TRIGGER trg_locations_updated_at BEFORE UPDATE ON locations FOR EACH ROW EXECUTE FUNCTION set_updated_at();



-- 7. ANIMALS (The Inventory)
-- ======================================================
CREATE TABLE animals (
    id UUID PRIMARY KEY DEFAULT gen_random_uuid(),
    species_id UUID NOT NULL REFERENCES species(id) ON DELETE RESTRICT,
    breed_id UUID REFERENCES breeds(id) ON DELETE SET NULL,
    location_id UUID REFERENCES locations(id) ON DELETE RESTRICT,

    sex sex_enum,
    age_months INT,
    weight_kg NUMERIC(8,2),
    color_markings VARCHAR(255),
    quantity INT NOT NULL DEFAULT 1,
    purpose purpose_enum,
    health_status health_status_enum DEFAULT 'healthy',
    vaccinated BOOLEAN DEFAULT FALSE,
    dewormed BOOLEAN DEFAULT FALSE,
    pregnancy_status pregnancy_status_enum NOT NULL DEFAULT 'unknown',
    calving_number INT,
    milk_yield_litre_per_day NUMERIC(8,3),
    ear_tag_no VARCHAR(100),
    description TEXT,
    
    deleted BOOLEAN NOT NULL DEFAULT FALSE,
    created_at TIMESTAMPTZ NOT NULL DEFAULT NOW(),
    updated_at TIMESTAMPTZ NOT NULL DEFAULT NOW()
);
CREATE TRIGGER trg_animals_updated_at BEFORE UPDATE ON animals FOR EACH ROW EXECUTE FUNCTION set_updated_at();

-- 8. LISTINGS (Denormalized for Read Performance)
-- ======================================================
CREATE TABLE listings (
    id UUID PRIMARY KEY DEFAULT gen_random_uuid(),
    seller_id UUID NOT NULL REFERENCES users(id) ON DELETE RESTRICT,
    animal_id UUID NOT NULL UNIQUE REFERENCES animals(id) ON DELETE CASCADE,

    title VARCHAR(255) NOT NULL,
    price NUMERIC(12,2),
    currency VARCHAR(10) DEFAULT 'INR',
    is_negotiable BOOLEAN DEFAULT FALSE,
    listing_type listing_type_enum DEFAULT 'sale',
    status listing_status_enum DEFAULT 'active',

    -- Counters (Updated via Batch Jobs)
    views_count BIGINT DEFAULT 0,
    bookmarks_count BIGINT DEFAULT 0,
    enquiries_call_count BIGINT DEFAULT 0,
    enquiries_whatsapp_count BIGINT DEFAULT 0,

    -- DENORMALIZED COLUMNS (Auto-filled by Trigger)
    -- These exist so the Home Feed doesn't need to join 4 tables
    filter_species_id UUID,
    filter_breed_id UUID,
    filter_sex sex_enum,
    filter_age_months INT,
    filter_pregnancy_status pregnancy_status_enum,
    filter_weight_kg NUMERIC(8,2),
    filter_calving_number INT,
    filter_milking_capacity NUMERIC(8,3),
    filter_location_geog GEOGRAPHY(POINT, 4326),
    
    -- AI Score
    listing_score INT,
    listing_score_status listing_score_status_enum DEFAULT 'pending',

    thumbnail_url TEXT, 

    -- FULL TEXT SEARCH (Auto-generated)
    search_vector tsvector GENERATED ALWAYS AS (
       to_tsvector('english', title)
    ) STORED,

    deleted_reason TEXT,
    deleted BOOLEAN NOT NULL DEFAULT FALSE,
    created_at TIMESTAMPTZ NOT NULL DEFAULT NOW(),
    updated_at TIMESTAMPTZ NOT NULL DEFAULT NOW()
);
CREATE TRIGGER trg_listings_updated_at BEFORE UPDATE ON listings FOR EACH ROW EXECUTE FUNCTION set_updated_at();



-- OPTIMIZED INDEXES
-- 1. Main Feed: Status + Species + Price (ignoring deleted)
CREATE INDEX idx_listings_feed_optimized ON listings (status, filter_species_id, price) WHERE deleted = FALSE;
-- 2. Near Me: Spatial Search
CREATE INDEX idx_listings_spatial ON listings USING GIST (filter_location_geog) WHERE deleted = FALSE;
-- 3. Search Bar: Text Search
CREATE INDEX idx_listings_search_gin ON listings USING GIN (search_vector);
-- 4. My Listings: Seller + Status
CREATE INDEX idx_listings_seller_status ON listings (seller_id, status) WHERE deleted = FALSE;

CREATE TABLE listing_media (
    id UUID PRIMARY KEY DEFAULT gen_random_uuid(),
    listing_id UUID NOT NULL REFERENCES listings(id) ON DELETE CASCADE,
    media_url TEXT NOT NULL,
    media_type media_type_enum NOT NULL,
    is_primary BOOLEAN NOT NULL DEFAULT FALSE,
    sort_order INT NOT NULL DEFAULT 0,
    deleted BOOLEAN NOT NULL DEFAULT FALSE,
    created_at TIMESTAMPTZ NOT NULL DEFAULT NOW()
);

CREATE TABLE sold_information (
    id UUID PRIMARY KEY DEFAULT gen_random_uuid(),
    listing_id UUID NOT NULL UNIQUE REFERENCES listings(id) ON DELETE CASCADE,
    sold_to_user_id UUID REFERENCES users(id) ON DELETE SET NULL,
    sale_price NUMERIC(12, 2),
    sale_location_id UUID REFERENCES locations(id) ON DELETE SET NULL,
    sale_date TIMESTAMPTZ,
    notes TEXT,
    attachment_urls TEXT[],
    deleted BOOLEAN NOT NULL DEFAULT FALSE,
    created_at TIMESTAMPTZ NOT NULL DEFAULT NOW(),
    updated_at TIMESTAMPTZ NOT NULL DEFAULT NOW()
);
CREATE TRIGGER trg_sold_information_updated_at BEFORE UPDATE ON sold_information FOR EACH ROW EXECUTE FUNCTION set_updated_at();

-- 9. ENGAGEMENT (Reviews, Analytics, Retention)
-- ======================================================
CREATE TABLE custom_requirements (
    id UUID PRIMARY KEY DEFAULT gen_random_uuid(),
    user_id UUID NOT NULL REFERENCES users(id) ON DELETE RESTRICT,
    animal_id UUID REFERENCES animals(id) ON DELETE SET NULL,
    requirement_text TEXT NOT NULL,
    status requirement_status_enum NOT NULL DEFAULT 'open',
    deleted BOOLEAN NOT NULL DEFAULT FALSE,
    created_at TIMESTAMPTZ NOT NULL DEFAULT NOW(),
    updated_at TIMESTAMPTZ NOT NULL DEFAULT NOW()
);
CREATE TRIGGER trg_custom_requirements_updated_at BEFORE UPDATE ON custom_requirements FOR EACH ROW EXECUTE FUNCTION set_updated_at();

-- New: High-speed analytics buffer
CREATE TABLE listing_analytics_events (
    id BIGSERIAL PRIMARY KEY,
    listing_id UUID NOT NULL REFERENCES listings(id) ON DELETE CASCADE,
    event_type analytics_event_type_enum NOT NULL,
    user_id UUID REFERENCES users(id) ON DELETE SET NULL,
    created_at TIMESTAMPTZ DEFAULT NOW()
);

-- Table for favorites
CREATE TABLE favorites (
    id UUID PRIMARY KEY DEFAULT gen_random_uuid(),
    user_id UUID NOT NULL REFERENCES users(id) ON DELETE RESTRICT,
    listing_id UUID NOT NULL REFERENCES listings(id) ON DELETE CASCADE,
    deleted BOOLEAN NOT NULL DEFAULT FALSE,
    created_at TIMESTAMPTZ NOT NULL DEFAULT NOW(),
    updated_at TIMESTAMPTZ NOT NULL DEFAULT NOW(),
    UNIQUE(user_id, listing_id)
);
CREATE TRIGGER trg_favorites_updated_at BEFORE UPDATE ON favorites FOR EACH ROW EXECUTE FUNCTION set_updated_at();

-- New: Reviews & Ratings
CREATE TABLE reviews (
    id UUID PRIMARY KEY DEFAULT gen_random_uuid(),
    listing_id UUID REFERENCES listings(id) ON DELETE SET NULL,
    reviewer_id UUID REFERENCES users(id),
    reviewee_id UUID REFERENCES users(id),
    listing_rating INT CHECK (listing_rating >= 1 AND listing_rating <= 5),
    seller_rating INT CHECK (seller_rating >= 1 AND seller_rating <= 5),
    comment TEXT,
    deleted BOOLEAN NOT NULL DEFAULT FALSE,
    created_at TIMESTAMPTZ DEFAULT NOW(),
    updated_at TIMESTAMPTZ DEFAULT NOW(),
    UNIQUE(listing_id, reviewer_id)
);
CREATE TRIGGER trg_reviews_updated_at BEFORE UPDATE ON reviews FOR EACH ROW EXECUTE FUNCTION set_updated_at();

-- 11. NOTIFICATIONS
-- ======================================================
CREATE TYPE notification_type_enum AS ENUM ('listing_expired', 'listing_enquiry', 'system_alert', 'other');

CREATE TABLE notifications (
    id UUID PRIMARY KEY DEFAULT gen_random_uuid(),
    user_id UUID NOT NULL REFERENCES users(id) ON DELETE CASCADE,
    type notification_type_enum NOT NULL,
    message TEXT NOT NULL,
    data JSONB, -- Related entity IDs etc.
    is_read BOOLEAN NOT NULL DEFAULT FALSE,
    created_at TIMESTAMPTZ NOT NULL DEFAULT NOW()
);
CREATE INDEX idx_notifications_user_unread ON notifications(user_id) WHERE is_read = FALSE;

-- 12. CHAT & COMMUNICATIONS
-- ======================================================
CREATE TABLE conversations (
    id UUID PRIMARY KEY DEFAULT gen_random_uuid(),
    buyer_id UUID NOT NULL REFERENCES users(id),
    seller_id UUID NOT NULL REFERENCES users(id),
    
    -- Denormalized Fields for Listing
    last_message_content TEXT,
    last_message_at TIMESTAMPTZ,
    last_call_at TIMESTAMPTZ,

    deleted BOOLEAN NOT NULL DEFAULT FALSE,
    created_at TIMESTAMPTZ NOT NULL DEFAULT NOW(),
    updated_at TIMESTAMPTZ NOT NULL DEFAULT NOW(),
    UNIQUE(buyer_id, seller_id)
);

CREATE TABLE messages (
    id BIGSERIAL PRIMARY KEY, -- Changed to BIGINT for cursor pagination
    conversation_id UUID NOT NULL REFERENCES conversations(id) ON DELETE CASCADE,
    sender_id UUID NOT NULL REFERENCES users(id),
    receiver_id UUID NOT NULL REFERENCES users(id),
    
    message_type message_type_enum NOT NULL DEFAULT 'text',
    content TEXT,
    
    -- Embedded Media
    message_media TEXT,
    media_type media_type_enum,
    media_metadata JSONB,

    is_read BOOLEAN NOT NULL DEFAULT FALSE,
    read_at TIMESTAMPTZ,
    deleted BOOLEAN NOT NULL DEFAULT FALSE,
    created_at TIMESTAMPTZ NOT NULL DEFAULT NOW(),
    updated_at TIMESTAMPTZ NOT NULL DEFAULT NOW()
);
CREATE TRIGGER trg_messages_updated_at BEFORE UPDATE ON messages FOR EACH ROW EXECUTE FUNCTION set_updated_at();

-- Efficient Index for Cursor Pagination: (conversation as filter, id as cursor)
CREATE INDEX idx_messages_pagination ON messages(conversation_id, id DESC) WHERE deleted = FALSE;

CREATE TABLE communication_records (
    communication_id BIGSERIAL PRIMARY KEY,
    conversation_id UUID REFERENCES conversations(id) ON DELETE SET NULL,
    buyer_id UUID NOT NULL REFERENCES users(id),
    seller_id UUID NOT NULL REFERENCES users(id),
    communication_type communication_type_enum NOT NULL,
    call_status call_status_enum NOT NULL,
    duration_seconds INT DEFAULT 0,
    call_recording_url TEXT,
    created_at TIMESTAMPTZ NOT NULL DEFAULT NOW(),
    updated_at TIMESTAMPTZ NOT NULL DEFAULT NOW()
);
CREATE TRIGGER trg_communication_records_updated_at BEFORE UPDATE ON communication_records FOR EACH ROW EXECUTE FUNCTION set_updated_at();

-- 11. AUTOMATION TRIGGERS
-- ======================================================

-- Trigger 1: Sync Animal/Location Data to Listing (The "Speed" Trigger)
CREATE OR REPLACE FUNCTION sync_listing_search_data()
RETURNS TRIGGER AS $$
DECLARE
    loc_geog GEOGRAPHY(POINT, 4326);
BEGIN
    -- 1. Sync Animal Info
    SELECT 
        species_id, breed_id, sex, age_months, 
        pregnancy_status, weight_kg, calving_number, milk_yield_litre_per_day
    INTO 
        NEW.filter_species_id, NEW.filter_breed_id, NEW.filter_sex, NEW.filter_age_months,
        NEW.filter_pregnancy_status, NEW.filter_weight_kg, NEW.filter_calving_number, NEW.filter_milking_capacity
    FROM animals WHERE id = NEW.animal_id;
    
    -- 2. Sync Location Info
    SELECT geog INTO loc_geog
    FROM locations 
    WHERE id = (SELECT location_id FROM animals WHERE id = NEW.animal_id);
    
    NEW.filter_location_geog := loc_geog;
    
    RETURN NEW;
END;
$$ LANGUAGE plpgsql;

CREATE TRIGGER trg_hydrate_listing
BEFORE INSERT OR UPDATE ON listings
FOR EACH ROW EXECUTE FUNCTION sync_listing_search_data();


-- Trigger 2: Auto-Update User Rating when Review is added
CREATE OR REPLACE FUNCTION update_seller_rating()
RETURNS TRIGGER AS $$
BEGIN
    UPDATE users
    SET 
        rating_count = (SELECT COUNT(*) FROM reviews WHERE reviewee_id = NEW.reviewee_id),
        rating_average = (SELECT AVG(seller_rating) FROM reviews WHERE reviewee_id = NEW.reviewee_id)
    WHERE id = NEW.reviewee_id;
    RETURN NEW;
END;
$$ LANGUAGE plpgsql;

CREATE TRIGGER trg_update_rating
AFTER INSERT OR UPDATE ON reviews
FOR EACH ROW EXECUTE FUNCTION update_seller_rating();


-- Trigger 3: Auto-Update Conversation Last Message & Call
CREATE OR REPLACE FUNCTION update_conversation_latest()
RETURNS TRIGGER AS $$
BEGIN
    IF TG_TABLE_NAME = 'messages' THEN
        UPDATE conversations
        SET 
            last_message_content = NEW.content,
            last_message_at = NEW.created_at,
            updated_at = NOW()
        WHERE id = NEW.conversation_id;
    ELSIF TG_TABLE_NAME = 'communication_records' THEN
        UPDATE conversations
        SET 
            last_call_at = NEW.created_at,
            updated_at = NOW()
        WHERE id = NEW.conversation_id;
    END IF;
    RETURN NEW;
END;
$$ LANGUAGE plpgsql;

CREATE TRIGGER trg_update_conversation_msg
AFTER INSERT ON messages
FOR EACH ROW EXECUTE FUNCTION update_conversation_latest();

CREATE TRIGGER trg_update_conversation_call
AFTER INSERT ON communication_records
FOR EACH ROW EXECUTE FUNCTION update_conversation_latest();

-- ======================================================
-- END OF SCRIPT
-- ======================================================