// R E A D C U   (PREPRESS)
// catalog number ???
//
//

get "ix.dfs"

// outgoing procedures
external
	[
	ReadCU
	]

// outgoing statics
//external
//	[
//	]
//static
//	[
//	]

// incoming procedures
external
	[
//PREPRESS
	WriteIXTempFile
	NoFile
	Scream
	TypeChar

//WINDOW
	PrePressWindowInit
	WindowRead
	WindowWrite
	WindowReadBlock
	WindowWriteBlock
	WindowCopy
	WindowGetPosition
	WindowSetPosition
	WindowEnd
	WindowClose
	GetPosRelative
	SetPosRelative

//SCAN
	ReadCom
	TypeForm

//UTIL
	FSGetX
	FSPut
	MulDiv

//OS
	SetBlock; Zero
	]

// incoming statics
//external
//	[
//	]

// internal statics
//static
//	[
//	]

// File-wide structure and manifest declarations.

structure STR[
	length byte
	char↑1,255 byte
	]
// Procedures


let ReadCU() be 
[
	let CD=FSGetX(256*2)
	SetBlock(CD,-1,256*2)	//-1 means no char defined
	let CWT=FSGetX(256*CharWidthsize)
	SetBlock(CWT, HNonExCode, 256*CharWidthsize)

	let str=vec 20
	ReadCom(str)		//Get file name
	let si=PrePressWindowInit(str,0)
	if si eq 0 then
		[
		NoFile(str)
		return
		]
	let scr=PrePressWindowInit(0)
	
	let height=WindowRead(si)
	let ww=WindowRead(si)

	let buf=FSGetX(height*ww)
	let baseline=0
	let globalminx=ww*16+1

until WindowEnd(si) do
	[
	let ch=WindowRead(si)		//Character code
	let width=WindowRead(si)
	if ch ls 0 % ch gr 255 then Scream("Illegal CU file.")
	TypeChar(ch)
	for i=height-1 to 0 by -1 do WindowReadBlock(si,buf+i*ww,ww)

//Now determine min,max black spots in both directions.
	let minx=width+1; let maxx=-1
	let miny=height+1; let maxy=-1

	for y=0 to height-1 do
		[
		let black=false
		let adr=buf+y*ww
		for j=0 to ww-1 do if adr!j ne 0 then black=true
		if black then
			[
			if y ls miny then miny=y
			if y gr maxy then maxy=y
			]
		]
	for x=0 to width-1 do
		[
		let black=false
		let adr=buf+(x rshift 4)
		let mask=#100000 rshift (x&#17)
		for j=1 to height do
			[
			black=black%(mask&@adr)
			adr=adr+ww
			]
		if black then
			[
			if x ls minx then minx=x
			if x gr maxx then maxx=x
			]
		]
	let p=CWT+ch*CharWidthsize
	WindowGetPosition(scr, CD+ch*2)

	Zero(p, CharWidthsize)
	(lv p>>CharWidth.WX)!0=width
	let space=(maxx ls minx)

	unless space then
		[
		p>>CharWidth.XL=minx	//For now -- not right
		p>>CharWidth.YB=miny	//Ditto
		p>>CharWidth.W=maxx-minx+1
		p>>CharWidth.H=maxy-miny+1
		]

	if minx ls globalminx then globalminx=minx
	if ch eq $A then baseline=miny	//CU convention -- kluge

	let oww=p>>CharWidth.W
	let oht=p>>CharWidth.H

	let a=nil
	a<<FHEAD.ns=oww
	a<<FHEAD.hw=(oht+15)/16
	WindowWrite(scr,a)

	for i=minx to maxx do
		[
		let imask=#100000 rshift (i&#17)
		let adr=buf+(i rshift 4)+(miny*ww)
		let wout=0
		let omask=#100000
		for j=miny to maxy do
			[
			if (@adr&imask) ne 0 then wout=wout%omask
			omask=omask rshift 1
			if omask eq 0 then 
				[
				WindowWrite(scr,wout)
				wout=0
				omask=#100000
				]
			adr=adr+ww
			]
		
		unless omask eq #100000 then WindowWrite(scr, wout)
		]

	TypeForm(0)
	]

	WindowClose(si)

//Now we must re-calculate some things.
// Baseline will probably have been set up.
	let p=CWT
	for i=0 to 255 do
		[
		p>>CharWidth.XL=p>>CharWidth.XL-globalminx
		p>>CharWidth.YB=p>>CharWidth.YB-baseline
		p=p+CharWidthsize
		]

//Now write the CDtemp file:
	let bc=256; let ec=-1
	for i=0 to 255 do if CD!(i*2) ne -1 then
		[
		if i ls bc then bc=i
		if i gr ec then ec=i
		]
	let nc=ec-bc+1
	if nc ls 0 then Scream("No characters recorded in CU file.")

	let fnx=vec IXLMax
	Zero(fnx, IXLMax)
	let fn=lv fnx>>IXN.Name
	for i=1 to str>>STR.length do
		[
		let c=str>>STR.char↑i
		if c eq $. then break
		fn>>STR.length=i
		fn>>STR.char↑i=c
		]
	let ix=vec IXLMax
	Zero(ix, IXLMax)
	ix>>IX.Type=IXTypeChars
	ix>>IX.bc=bc
	ix>>IX.ec=ec
	ix>>IX.siz=MulDiv(10,635,18)	//"10 point" font
	
	let ofil=PrePressWindowInit(-1)
	WriteIXTempFile(ofil, fnx, ix)	//Write it out once.

	WindowGetPosition(ofil, lv ix>>IX.sa)
	WindowWriteBlock(ofil, CWT, nc*CharWidthsize)

	let rel=vec 1
	WindowGetPosition(ofil, rel)
	WindowWriteBlock(ofil, CD, nc*2)	//Wrong now.

	for i=bc to ec do if CD!(i*2) ne -1 then
		[
		let i2=i*2
		WindowSetPosition(scr, CD+i2)
		GetPosRelative(ofil, rel, CD+i2)
		let a=WindowRead(scr)
		let nw=a<<FHEAD.ns*a<<FHEAD.hw
		WindowWrite(ofil, a)
		let dnum=vec 1
		dnum!0=0; dnum!1=nw
		WindowCopy(scr, ofil, dnum)
		]

	let tl=vec 1
	WindowGetPosition(ofil, tl)
	GetPosRelative(ofil, lv ix>>IX.sa, lv ix>>IX.len)

	WindowSetPosition(ofil, table [ 0;0 ])
	WriteIXTempFile(ofil, fnx, ix)
	WindowWriteBlock(ofil,CWT+bc*CharWidthsize,nc*CharWidthsize)
	WindowWriteBlock(ofil,CD+bc*2,nc*2)

	WindowClose(ofil, tl)
	WindowClose(scr)
]