/*
====================================================================================
 Script: single_price_call.pg.sql
 Purpose: Single price call logic for a specific scenario (PostgreSQL)
 -----------------------------------------------------------------------------------
 Description:
   - Accepts a single pricing scenario (bill, ship, part, v1ds, vol)
   - Enriches with customer, channel, tier, pack quantity, price level, and part group
   - Looks up and applies target price, price history, list price, and guidance logic
   - Builds a JSON explanation and UI JSON for the scenario

 Inputs:
   - bill, ship, part, v1ds, vol (function arguments)
   - Reference tables: pricequote.target_prices, pricequote.lastpricedetail, pricequote.pricelist_ranged
   - Customer/item reference: rlarp.cust, CMS.CUSLG.itemm, CMS.CUSLG.IPRCBHC

 Outputs:
   - Returns a single enriched row with all pricing and explanation fields

 Key Business Logic:
   - Channel/tier/customer resolution based on bill/ship codes
   - Target price and math lookup by segment, channel, tier, and volume
   - Price history precedence and extraction via helper function
   - List price selection: lowest valid price for the scenario
   - Guidance logic: computed from target, last, and list prices

 Dependencies:
   - pricequote.guidance_logic (function)
   - pricequote.pick_last_price_from_hist (function)

 Notes:
   - Designed for single-row pricing queries (API or UI)
   - Assumes all referenced tables and functions exist
   - See also: matrix_guidance.pg.sql for batch/matrix logic
====================================================================================
*/

--DROP FUNCTION pricequote.single_price_call(text,text,text,text,numeric);

CREATE OR REPLACE FUNCTION pricequote.single_price_call(
    _bill TEXT,
    _ship TEXT,
    _part TEXT,
    _v1ds TEXT,
    _vol NUMERIC
)
RETURNS TABLE (
    bill TEXT,
    ship TEXT,
    part TEXT,
    stlc TEXT,
    v1ds TEXT,
    vol NUMERIC,
    chan TEXT,
    cust TEXT,
    tier TEXT,
    pltq NUMERIC,
    plevel TEXT,
    partgroup TEXT,
    part_v1ds TEXT,
    v0ds TEXT,
    curstd_orig NUMERIC,
    futstd_orig NUMERIC,
    curstd NUMERIC,
    futstd NUMERIC,
    curstd_last NUMERIC,
    futstd_last NUMERIC,
    customized TEXT,
    last_premium NUMERIC,
    last_premium_method TEXT,
    last_price_norm NUMERIC,
    last_isdiff TEXT,
    last_v0ds TEXT,
    tprice_last NUMERIC,
    last_price NUMERIC,
    last_qty NUMERIC,
    last_dataseg TEXT,
    last_date DATE,
    last_order TEXT,
    last_quote TEXT,
    last_source TEXT,
    tprice NUMERIC,
    tmath JSONB,
    volume_range TEXT,
    listprice NUMERIC,
    listcode TEXT,
    listprice_eff NUMERIC,
    list_relevance TEXT,
    guidance_price NUMERIC,
    guidance_reason TEXT,
    expl JSONB,
    ui_json JSONB
) AS $$
DECLARE
    -----------input parameters--------------
    -- _bill 
    -- _ship
    -- _part 
    -- _v1ds 
    -- _vol
    ------------step 1 lookup scenario------------
    _chan TEXT;
    _tier TEXT;
    _cust TEXT;
    _pltq NUMERIC;
    _plevel TEXT;
    _partgroup TEXT;
    _stlc TEXT;
    _part_v1ds TEXT;
    _v0ds TEXT;
    _curstd_orig NUMERIC;
    _futstd_orig NUMERIC;
    _calculated_pallets INT;
    _exact_pallets NUMERIC;
    _customized TEXT := '';
    ----------- step 2 last price------------------
    _hist JSONB := '{}'::jsonb;
    _last JSONB;
    _last_price NUMERIC;
    _last_source TEXT;
    _last_date DATE;
    _last_qty NUMERIC;
    _last_dataseg TEXT;
    _last_v0ds TEXT;
    _last_order TEXT;
    _last_quote TEXT;
    _last_isdiff TEXT;
	_last_part TEXT;
    ------------step 3 lookup target---------------
    _tprice NUMERIC(20,5);
    _tmath JSONB;
    _volume_range TEXT;
    _tprice_last NUMERIC(20,5);
    ------------step 4 normalize last price--------
    _curstd NUMERIC;
    _futstd NUMERIC;
    _curstd_last NUMERIC;
    _futstd_last NUMERIC;
    _last_premium NUMERIC;
    _last_price_norm NUMERIC;
    _last_premium_method TEXT;
    ------------step 5 list price lookup-----------
    _list_price NUMERIC;
    _list_code TEXT;
    _listprice_eff NUMERIC;
    _list_relevance TEXT;
        ------------step 6 compute guidance------------
    _guidance_price NUMERIC;
    _guidance_reason TEXT;
    ------------step 7 build json------------------
    _expl JSONB := '{}'::jsonb;
    _ui_json JSONB := '{}'::jsonb;
BEGIN
    ------------------------------------------------------------------
    -- Step 1: Resolve customer metadata and part master data
    ------------------------------------------------------------------
    SELECT
        CASE SUBSTRING(bc.cclass, 2, 3)
            WHEN 'DIS' THEN 
                CASE SUBSTRING(sc.cclass, 2, 3)
                    WHEN 'DIS' THEN 'WHS'
                    ELSE 'DRP'
                END
            ELSE 'DIR'
        END chan,
        CASE SUBSTRING(bc.cclass, 2, 3)
            WHEN 'DIR' THEN bc.tier
            ELSE COALESCE(sc.tier, bc.tier)
        END tier,
        CASE SUBSTRING(bc.cclass, 2, 3)
            WHEN 'DIS' THEN 
                CASE SUBSTRING(sc.cclass, 2, 3)
                    WHEN 'DIS' THEN bc.dba
                    ELSE sc.dba
                END
            ELSE bc.dba
        END cust,
        i.mpck,
        CASE SUBSTRING(bc.cclass, 2, 3)
            WHEN 'DIS' THEN 
                CASE SUBSTRING(sc.cclass, 2, 3)
                    WHEN 'DIS' THEN sc.plevel
                    ELSE bc.plevel
                END
            ELSE bc.plevel
        END plevel,
        substring(_part,1,8) stlc,
        i.partgroup,
        i.v1ds part_v1ds,
        CASE substring(_v1ds,4,1) WHEN 'B' THEN 'B' ELSE 'C' END || CASE substring(_v1ds,6,1) WHEN 'L' THEN 'L' WHEN 'P' THEN 'P' ELSE '' END v0ds,
        i.curstdus,
        i.futstdus,
        FLOOR(_vol / NULLIF(i.mpck, 0)),
        ROUND(_vol / NULLIF(i.mpck, 0), 5)
    INTO 
         _chan
        ,_tier
        ,_cust
        ,_pltq
        ,_plevel
        ,_stlc
        ,_partgroup
        ,_part_v1ds
        ,_v0ds
        ,_curstd_orig
        ,_futstd_orig
        ,_calculated_pallets
        ,_exact_pallets
    FROM 
        rlarp.cust bc
        LEFT JOIN rlarp.cust sc ON 
            sc.code = _ship
        LEFT JOIN "CMS.CUSLG".itemm i ON 
            i.item = _part
    WHERE 
        bc.code = _bill;

    -- Customized flag
    IF _part_v1ds IS NOT NULL AND _v1ds IS NOT NULL AND _part_v1ds <> _v1ds THEN
        _customized := 'Customized';
    END IF;

	-- RAISE NOTICE 'Debug Inputs => stlc: "%", v1ds: "%", chan: "%", tier: "%", pallets: "%" , pltq: "%"',
	--    _stlc, _v1ds, _chan, _tier, _calculated_pallets, _pltq;

	--------------------------------------------------------------------------------
	-- Step 3: Lookup Last Price
	--------------------------------------------------------------------------------
    SELECT 
        lp.part_stats 
    INTO 
        _hist
    FROM 
        pricequote.lastpricedetail lp
    WHERE 
        lp.customer = _cust
        AND lp.partgroup = _partgroup;

    _last := pricequote.pick_last_price_from_hist(_hist, _v1ds);
    _last_price := (_last->>'price')::numeric;
    _last_source := _last->>'source';
    _last_date := (_last->>'odate')::date;
    _last_qty := (_last->>'qty')::numeric;
    _last_dataseg := _last->>'datasegment';
    _last_v0ds := 
        CASE substring(_last_dataseg,4,1) WHEN 'B' THEN 'B' ELSE 'C' END ||
        CASE substring(_last_dataseg,6,1) WHEN 'L' THEN 'L' WHEN 'P' THEN 'P' ELSE '' END;
    _last_order := _last->>'ordnum';
    _last_quote := _last->>'quoten';
    IF _last_dataseg IS NOT NULL AND _v1ds IS NOT NULL AND _last_dataseg <> _v1ds THEN
        _last_isdiff := 'Last Sale Diff Part';
    END IF;
	_last_part := _last->>'part';

    ------------------------------------------------------------------
    -- Step 2: Target price logic (current and for last_dataseg)
    ------------------------------------------------------------------
    SELECT 
         tp.price
        ,to_json(tp.math)
        ,tp.vol::text
    INTO 
         _tprice
        ,_tmath
        ,_volume_range
    FROM 
        pricequote.target_prices tp
    WHERE 
          tp.stlc = _stlc
      AND tp.ds = _v1ds
      AND tp.chan = _chan
      AND tp.tier = _tier
      AND tp.vol @> _calculated_pallets;

	-- RAISE NOTICE 'Debug: tprice=%, tmath=%, volume_range=%',
	--    _tprice, _tmath, _volume_range;


    -- Target price for last_dataseg
    SELECT 
        tp.price
    INTO 
        _tprice_last
    FROM 
        pricequote.target_prices tp
    WHERE 
          tp.stlc = _stlc
      AND tp.ds = _last_dataseg
      AND tp.chan = _chan
      AND tp.tier = _tier
      AND FLOOR(_vol / NULLIF(_pltq, 0))::int <@ tp.vol;

    ------------------------------------------------------------------
    -- Step 4: Cost data for normalization
    ------------------------------------------------------------------
    -- Current/future standard for requested v1ds
    SELECT 
        curstdus, futstdus 
    INTO 
        _curstd, _futstd
    FROM 
        "CMS.CUSLG".itemm i
    WHERE 
            i.item = _part 
        AND i.v1ds = _v1ds;

    -- Current/future standard for last_dataseg
    SELECT 
        curstdus, futstdus 
    INTO 
        _curstd_last, _futstd_last
    FROM 
        "CMS.CUSLG".itemm i
    WHERE 
            i.item = _part 
        AND i.v1ds = _last_dataseg;

    ------------------------------------------------------------------
    -- Step 5: Normalize last price if needed
    ------------------------------------------------------------------
    IF _last_isdiff IS NOT NULL THEN
        IF _tprice_last IS NOT NULL AND _tprice IS NOT NULL AND _tprice_last <> 0 THEN
            _last_premium := ROUND(_tprice / _tprice_last,5);
            _last_price_norm := ROUND(_last_price * (_tprice / _tprice_last), 5);
            _last_premium_method := 'Target Price Ratio';
        ELSIF _curstd_last IS NOT NULL AND _curstd IS NOT NULL AND _curstd_last <> 0 THEN
            _last_premium := _curstd / _curstd_last;
            _last_price_norm := ROUND(_last_price * (_curstd / _curstd_last), 5);
            _last_premium_method := 'Cost Ratio';
        ELSE
            _last_price_norm := _last_price;
            _last_premium_method := 'Unknown';
        END IF;
    ELSE
        _last_price_norm := _last_price;
    END IF;

    ------------------------------------------------------------------
    -- Step 6: List price logic
    ------------------------------------------------------------------
    SELECT 
         pr.price::numeric(20,5)
        ,pr.jcplcd
    INTO 
        _list_price
        ,_list_code
    FROM 
        "CMS.CUSLG".IPRCBHC i
        JOIN pricequote.pricelist_ranged pr ON 
                pr.jcplcd = TRIM(i.jbplcd)
            AND pr.jcpart = _part
            AND _vol >= pr.vb_from
            AND (_vol < pr.vb_to OR pr.vb_to IS NULL)
    WHERE 
            TRIM(i.jbplvl) = TRIM(_plevel)
        AND CURRENT_DATE BETWEEN i.jbfdat AND i.jbtdat
    ORDER BY 
        pr.price ASC
    LIMIT 1;

    -- List price relevance
    IF _customized <> '' THEN
        _listprice_eff := NULL;
        _list_relevance := 'Ignore - Customized';
    ELSE
        _listprice_eff := _list_price;
        _list_relevance := '';
    END IF;

    ------------------------------------------------------------------
    -- Step 7: Compute guidance price and embed it
    ------------------------------------------------------------------
    SELECT 
         gl.guidance_price
        ,gl.guidance_reason
    INTO 
         _guidance_price
        ,_guidance_reason
    FROM pricequote.guidance_logic(_tprice, _last_price_norm, _listprice_eff, _last_date) gl;

    ------------------------------------------------------------------
    -- Step 8: Build explanation JSON
    ------------------------------------------------------------------
    _expl := 
		jsonb_build_object(
			'last',
			jsonb_build_object(
				'last_part', _last_part,
		        'last_price', _last_price,
		        'last_qty', _last_qty,
		        'last_dataseg', _last_dataseg,
		        'last_v0ds', _last_v0ds,
		        'last_source', _last_source,
		        'last_date', _last_date,
		        'last_order', _last_order,
		        'last_quote', _last_quote,
		        'last_isdiff', _last_isdiff,
				'last_premium', _last_premium,
	    	    'last_premium_method', _last_premium_method,
		        'last_price_norm', _last_price_norm,
		        'tprice_last', _tprice_last
			),
			'scenario',
			jsonb_build_object(
				'calculated_pallets', FLOOR(_vol / NULLIF(_pltq, 0)),
		        'exact_pallets', ROUND(_vol / NULLIF(_pltq, 0), 5),
		        'customer', _cust,
		        'channel', _chan,
		        'tier', TRIM(_tier),
				'v1ds', _v1ds,
		        'v0ds', _v0ds,
		        'part_v1ds', _part_v1ds,
		        'customized', _customized
			),
			'cost',
			jsonb_build_object(
				'curstd_orig', _curstd_orig,
		        'futstd_orig', _futstd_orig,
		        'curstd_last', _curstd_last,
		        'futstd_last', _futstd_last,
		        'curstd', _curstd,
		        'futstd', _futstd
			),
			'targets',
			jsonb_build_object(
		        'target_price', _tprice,
		        'target_math', _tmath
			),
			'list',
			jsonb_build_object(
		        'listcode', _list_code,
		        'listprice', _list_price,
		        'listprice_eff', _listprice_eff,
		        'list_relevance', _list_relevance
			),
        'guidance_price', _guidance_price,
        'guidance_reason', _guidance_reason
    );

    ------------------------------------------------------------------
    -- Step 9: Build UI JSON (panels)
    ------------------------------------------------------------------
    _ui_json := jsonb_build_object(
        'details', jsonb_build_array(
            ------------------------------------------
            -- history 
            ------------------------------------------
            jsonb_build_object(
                'label', 'History',
                'details', jsonb_build_array(
                    jsonb_build_object(
                        'label', CASE WHEN _last_price IS NOT NULL THEN 'Last Sale: ' || _last_date ELSE 'No Recent' END,
                        'value', COALESCE(_last_price,0),
                        'type', 'currency',
                        'note', CASE WHEN _last_price IS NOT NULL THEN 
							CASE _last_source
			                    	WHEN 'mrq' THEN 'Recent similar ' || _last_part || ' ' 
			                    	WHEN 'mrs' THEN 'Recent similar ' || _last_part || ' ' 
			                    	WHEN 'dsq' THEN 'Last quote'
			                    	WHEN 'dss' THEN 'Last sale'
			                    	ELSE ''
			                END || 
                            CASE WHEN COALESCE(_last_order, '0') = '0' THEN ' Qt# ' || COALESCE(_last_quote, '') ELSE ' Ord# ' || COALESCE(_last_order, '') END
                            ELSE NULL END
                    )
                )
            ),
            ------------------------------------------
            -- price list
            ------------------------------------------
            jsonb_build_object(
                'label', 'List',
                'details', jsonb_build_array(
                    jsonb_build_object(
                        'label', 'List:' || COALESCE(_list_code, ''),
                        'value', _list_price,
                        'type', 'currency',
                        'note', _list_relevance
                    )
                )
            ),
            ------------------------------------------
            -- history
            ------------------------------------------
            jsonb_build_object(
                'label', 'Target Calculation',
                'details', 
                -- jsonb_build_array(
                    (
                    SELECT 
                        jsonb_agg(
                            jsonb_build_object(
                                ----------------------label------------------------------------------------
                                'label',CASE WHEN value <> '' THEN RTRIM(SUBSTRING(value,1,18)) ELSE 'No Target' END,
                                ----------------------value------------------------------------------------
                                'value',CASE WHEN value <> '' THEN 
                                            SUBSTRING(value,23,7)::NUMERIC(20,5) + 
                                            CASE SUBSTRING(value,19,1) WHEN '+' THEN 0 ELSE -1 END 
                                        ELSE 
                                            0 
                                        END,
                                ----------------------type-------------------------------------------------
                                'type', CASE WHEN value <> '' THEN 
                                            CASE SUBSTRING(value,19,1) 
                                                WHEN '+' THEN 'currency' 
                                                ELSE 'Percent' 
                                            END 
                                        ELSE '' END,
                                ----------------------note-------------------------------------------------
                                'note',CASE WHEN value <> '' THEN 
                                            CASE SUBSTRING(value,19,1) 
                                                WHEN '+' THEN 'Price' 
                                                ELSE 'Premium' 
                                            END 
                                        ELSE '' END
                                )
                        )
                        FROM jsonb_array_elements_text(COALESCE(_tmath,'{}'::jsonb)) ae
                    )
                    ||jsonb_build_object('label','Price','value',_tprice,'type','currency','note','Total')
                -- )
            ),
            ------------------------------------------
            -- history
            ------------------------------------------
            jsonb_build_object(
                'label', 'Guidance',
                'details', jsonb_build_array(
                    jsonb_build_object(
                        'label', 'Price',
                        'value', _guidance_price,
                        'type', 'currency',
                        'note', _guidance_reason
                    )
                )
            )
        ),
        'data', _expl
    );

    ------------------------------------------------------------------
    -- Final: Return row
    ------------------------------------------------------------------
    RETURN QUERY
    SELECT 
        _bill, _ship, _part, _stlc, _v1ds, _vol,
        _chan, _cust, _tier, _pltq, _plevel, _partgroup, _part_v1ds, _v0ds,
        _curstd_orig, _futstd_orig, _curstd, _futstd, _curstd_last, _futstd_last,
        _customized, _last_premium, _last_premium_method, _last_price_norm, _last_isdiff, _last_v0ds, _tprice_last,
        _last_price, _last_qty, _last_dataseg, _last_date, _last_order, _last_quote, _last_source,
        _tprice, _tmath, _volume_range,
        _list_price, _list_code, _listprice_eff, _list_relevance,
        _guidance_price, _guidance_reason,
        _expl, _ui_json;
END;
$$ LANGUAGE plpgsql;