pta.js

/*
Pta.js
Programming Textarea
(C) Michael D Leidel, 2016
All Rights Reserved.
If you use this library it 
must display this comment block.
-------------------------------
After the library is loaded..
activate with: Pta.listeners.initialize(textarea id);
Find functions:
Pta.findr.replaceOne(textarea id, text to find, replace text)
Pta.insClip(textarea id, text to insert)
*/

var Pta = Pta || {};
Pta.listeners = {initialize:function(sid) {
	var Oid = document.getElementById(sid);
	Pta.listeners.setTabs(Oid);
	Oid.style.tabSize = 4;
	Pta.listeners.setIndent(Oid);
	Pta.listeners.setJoinLines(Oid);
	Pta.listeners.setMatching(Oid);
	Pta.listeners.setDupChr(Oid);
	Pta.listeners.setZen(Oid);
	Pta.listeners.setLineNbr(Oid);
}, setTabs:function(TAo) {
	TAo.addEventListener("keydown", function(event) {
		if (event.keyCode === 9 && !event.shiftKey) {
			event.preventDefault();
			var p1, p2;
			var sels = TAo.selectionStart, sele = TAo.selectionEnd, txt = TAo.value;
			if (sels === sele) {
				TAo.value = txt.slice(0, sels) + "\t" + txt.slice(sele);
				TAo.selectionStart = sels + 1;
				TAo.selectionEnd = sels + 1;
				return;
			}
			var stxt = txt.slice(sels, sele);
			var nl = Pta.countNewLines(stxt);
			if (txt.charCodeAt(sele - 1) !== 10) {
				let i1, i2;
				let len = stxt.length;
				while (1) {
					let si = TAo.selectionEnd;
					i1 = txt.indexOf(stxt, si);
					i2 = i1 + len;
					if (i1 >= 0) {
						TAo.selectionStart = i1;
						TAo.selectionEnd = i2;
					} else {
						if (si > 0) {
							TAo.selectionStart = 0;
							TAo.selectionEnd = 0;
							continue;
						}
					}
					return;
				}
			}
			stxt = stxt.replace(/\s+$/g, "");
			stxt = stxt.replace(new RegExp("\n", "g"), "\n\t");
			p1 = txt.slice(0, sels);
			p2 = txt.slice(sele);
			TAo.value = p1 + "\t" + stxt + "\n" + p2;
			TAo.selectionStart = sels;
			TAo.selectionEnd = sele + nl;
			return;
		}
	});
	TAo.addEventListener("keydown", function(event) {
		if (event.keyCode === 9 && event.shiftKey) {
			event.preventDefault();
			var p1, p2;
			var sels = TAo.selectionStart, sele = TAo.selectionEnd, txt = TAo.value;
			if (sels === sele) {
				p1 = txt.slice(0, sels - 1);
				p2 = txt.slice(sels);
				TAo.value = p1 + p2;
				TAo.selectionStart = sels - 1;
				TAo.selectionEnd = sels - 1;
				return;
			}
			var stxt = txt.slice(sels, sele);
			var nl = Pta.countNewLines(stxt);
			if (stxt.charCodeAt(0) > 32) {
				return;
			}
			stxt = stxt.replace(new RegExp("\n\t", "g"), "\n");
			p1 = txt.slice(0, sels);
			p2 = txt.slice(sele);
			TAo.value = p1 + stxt.slice(1) + p2;
			TAo.selectionStart = sels;
			TAo.selectionEnd = sele - nl;
			return;
		}
	});
}, setJoinLines:function(TAo) {
	TAo.addEventListener("keydown", function(event) {
		if (String.fromCharCode(event.which).toLowerCase() === "t" && event.altKey) {
			event.preventDefault();
			var slines, p1, p2;
			var sels = TAo.selectionStart, sele = TAo.selectionEnd, txt = TAo.value;
			slines = txt.slice(sels, sele);
			if (slines === "") {
				alert("No Lines Selected to Join");
				return;
			}
			p1 = txt.slice(0, sels);
			p2 = txt.slice(sele);
			slines = slines.replace(/\n/g, "");
			TAo.value = p1 + slines + p2;
			TAo.selectionEnd = sels;
			return;
		}
	});
}, setIndent:function(TAo) {
	TAo.addEventListener("keydown", function(event) {
		if (event.keyCode === 13 && !event.ctrlKey) {
			event.preventDefault();
			var inx, stx, chx, v = TAo.value, s = TAo.selectionStart, e = TAo.selectionEnd;
			for (inx = s - 1; inx > 0; inx-=1) {
				if (v.charCodeAt(inx) === 10) {
					break;
				}
			}
			stx = String.fromCharCode(10);
			if (inx > 0) {
				inx+=1;
			}
			chx = v.charCodeAt(inx);
			while (chx === 32 || chx === 9) {
				stx += String.fromCharCode(chx);
				inx+=1;
				chx = v.charCodeAt(inx);
			}
			TAo.value = v.slice(0, s) + stx + v.slice(e);
			TAo.selectionStart	= s + stx.length;
			TAo.selectionEnd = s + stx.length;
			return;
		}
	});
}, setMatching:function(TAo) {
	TAo.addEventListener("keydown", function(event) {
		if (String.fromCharCode(event.which).toLowerCase() === "q" && event.altKey) {
			event.preventDefault();
			matchBrace();
		}
	});
	TAo.addEventListener("click", function(event) {
		if (event.ctrlKey) {
			event.preventDefault();
			matchBrace();
		}
	});

	function matchBrace() {
		var sta = TAo.value;
		var cpos = TAo.selectionStart;
		var ch = sta.charAt(cpos);
		if ("{(".indexOf(ch) < 0) {
			cpos-=1;
			ch = sta.charAt(cpos);
			if ("})".indexOf(ch) < 0) {
				return;
			}
		}
		if (ch === "}") {
			doMatchBk("}", "{", cpos);
		} else {
			if (ch === "{") {
				doMatchFw("{", "}", cpos);
			} else {
				if (ch === ")") {
					doMatchBk(")", "(", cpos);
				} else {
					if (ch === "(") {
						doMatchFw("(", ")", cpos);
					}
				}
			}
		}
	}
	function doMatchBk(cb1, cb2, cpos) {
		var inx, cbx, cnt = 0;
		var sta = TAo.value;
		for (inx = cpos - 1; inx >= 0; inx-=1) {
			cbx = sta.charAt(inx);
			if (cbx === cb2) {
				if (cnt === 0) {
					TAo.selectionStart = inx;
					break;
				} else {
					cnt-=1;
				}
			} else {
				if (cbx === cb1) {
					cnt+=1;
				}
			}
		}
		if (inx < 0) {
			alert("Match not found");
		}
	}
	function doMatchFw(cb1, cb2, cpos) {
		var inx, cbx, len, cnt = 0;
		var sta = TAo.value;
		len = sta.length;
		for (inx = cpos + 1; inx < len; inx+=1) {
			cbx = sta.charAt(inx);
			if (cbx === cb2) {
				if (cnt === 0) {
					TAo.selectionEnd = inx + 1;
					break;
				} else {
					cnt-=1;
				}
			} else {
				if (cbx === cb1) {
					cnt+=1;
				}
			}
		}
		if (inx >= len) {
			alert("Match not found");
		}
	}
}, setDupChr:function(TAo) {
	TAo.addEventListener("keydown", function(event) {
		if (String.fromCharCode(event.which).toLowerCase() === "d" && event.altKey) {
			event.preventDefault();
			var inx, chx, v = TAo.value, s = TAo.selectionStart, e = TAo.selectionEnd;
			var ct = 0;
			for (inx = s - 1; inx > 0; inx-=1) {
				ct+=1;
				if (v.charCodeAt(inx) === 10) {
					break;
				}
			}
			while (inx > 0) {
				inx-=1;
				if (v.charCodeAt(inx) === 10) {
					break;
				}
			}
			if (v.charCodeAt(inx) !== 10) {
				ct-=1;
			}
			inx += ct;
			chx = v.charAt(inx);
			TAo.value = v.slice(0, s) + chx + v.slice(e);
			TAo.selectionStart = s + 1;
			TAo.selectionEnd = s + 1;
			return;
		}
	});
}, setZen:function(TAo) {
	var lastWrap = "";
	TAo.addEventListener("keydown", function(event) {
		if (String.fromCharCode(event.which).toLowerCase() === "z" && event.altKey) {
		zentag();
			event.preventDefault();
			return;
		}
	});
	TAo.addEventListener("keydown", function(event) {
		if (String.fromCharCode(event.which).toLowerCase() === "a" && event.altKey) {
			zentage(0);
			event.preventDefault();
			return;
		}
	});
	TAo.addEventListener("keydown", function(event) {
		if (String.fromCharCode(event.which).toLowerCase() === "w" && event.altKey) {
			zentage(1);
			event.preventDefault();
			return;
		}
	});

	function zentage(m) {
		var p1, p2, stag, t1, t2, stxt;
		var sels = TAo.selectionStart, sele = TAo.selectionEnd, txt = TAo.value;
		stxt = txt.slice(sels, sele);
		p1 = txt.slice(0, sels);
		p2 = txt.slice(sele);
		if (sels === sele) {
			alert("nothing selected");
			return;
		}
		if (m === 0) {
			stag = prompt("Enter tag abbreviation\n or command");
			lastWrap = stag;
		} else {
			stag = lastWrap;
		}
		if (stag === null) {
			return;
		}
		if (stag === "") {
			return;
		}
		if (stag === "/*") {
			t1 = "/* ";
			t2 = " */";
		} else {
			if (stag === "<!") {
				t1 = "\x3c!-- ";
				t2 = " --\x3e";
			} else {
				if (stag === "ucase") {
					t1 = "";
					t2 = "";
					stxt = stxt.toUpperCase();
				} else {
					if (stag === "lcase") {
						t1 = "";
						t2 = "";
						stxt = stxt.toLowerCase();
					} else {
						if (stag === "\"") {
							t1 = "\"";
							t2 = "\"";
						} else {
							if (stag === "'") {
								t1 = "'";
								t2 = "'";
							} else {
								if (stag === "$") {
									t1 = "${";
									t2 = "}";
								} else {
									t1 = "<" + stag + ">";
									t2 = "</" + stag + ">";
								}
							}
						}
					}
				}
			}
		}
		txt = p1 + t1 + stxt + t2 + p2;
		TAo.value = txt;
		TAo.selectionEnd = txt.length - p2.length;
		TAo.selectionStart = txt.length - p2.length;
		return;
	}

	function zentag() {
		var inx, p1, p2, stag, cpos;
		var sels = TAo.selectionStart, sele = TAo.selectionEnd, txt = TAo.value;
		stag = txt.slice(sels, sele);
		cpos = 0;	// for ^ position
		if (stag === "") {
			while (sele < txt.length) {
				if (txt.charCodeAt(sele) < 49) {
					break;
				}
				sele +=1;
			}
			while (sels > 0) {
				sels -= 1;
				if (txt.charCodeAt(sels) < 49) {
					sels += 1;
					break;
				}
			}
			stag = txt.slice(sels, sele);
		}
		if (stag === "") {
			alert("No Key Word to Match");
			return;
		}

		p1 = txt.slice(0, sels);
		p2 = txt.slice(sele);
		for (inx = 0; inx < atags.length; inx+=1) {	
			if (stag === atags[inx].tag) {
				let t = p1 + atags[inx].tagx + p2;
				// try to set cursor at ^
				cpos = t.indexOf("^", sels);
				if (cpos === -1) {
					TAo.value = t;
					TAo.selectionEnd = t.length - p2.length;
					TAo.selectionStart = t.length - p2.length;
				} else {
						p1 = t.slice(0, cpos);
						p2 = t.slice(cpos+1);
						TAo.value = p1 + p2;
						TAo.selectionEnd = cpos;
						TAo.selectionStart = cpos;
					}
				return;
			}
		}

		// specific tag not found, use the word by the cursor

		txt = p1 + "<" + stag + "></" + stag + ">" + p2;
		cpos = txt.indexOf("><", sels);
		cpos+=1;
		TAo.value = txt;
		TAo.selectionEnd = cpos;
		TAo.selectionStart = cpos;
		return;
	}
}, setLineNbr:function(TAo) {
	var gSave4LnNbr = "";
	var sout;
	TAo.addEventListener("keydown", function(event) {
		if (String.fromCharCode(event.which).toLowerCase() === "n" && event.altKey) {
			event.preventDefault();
			if (gSave4LnNbr === "") {
				sout = "1\t\t";
				let lc = 2, inx, cc, slc;
				let t = TAo.value;
				gSave4LnNbr = t;
				for (inx = 0; inx < t.length - 1; inx+=1) {
					cc = t.charAt(inx);
					if (cc === "\n") {
						slc = lc.toString();
						while (slc.length < 4) {
							slc += " ";
						}
						sout += cc + slc + "\t\t";
						lc+=1;
					} else {
						sout += cc;
					}
				}
				TAo.value = sout;
				TAo.readOnly=true;
			} else {
				TAo.readOnly=false;
				TAo.value = gSave4LnNbr;
				gSave4LnNbr = "";
			}
		}
	});
}
};	// END Pta.listeners

Pta.findr = {findText:function(Oid, targ) {
	if (arguments.length !== 2) {
		alert("missing arguments for findText");
		return;
	}
	var TAo = document.getElementById(Oid);
	var targ_id = document.getElementById(targ);
	var i1, i2;
	var stxt = TAo.value;
	var len = targ_id.value.length;
	var si = TAo.selectionEnd;
	i1 = stxt.indexOf(targ_id.value, si);
	i2 = i1 + len;
	if (i1 >= 0) {	// match found
		TAo.selectionStart = i1;
		TAo.selectionEnd = i2;
		TAo.focus();
		return;
	} else {
		if (si > 0) {	// back to top
			TAo.selectionStart = 0;
			TAo.selectionEnd = 0;
			Pta.findr.findText(Oid, targ);
		} else {
			return;
		}
	}
}, replaceOne:function(Oid, targ, chng) {
	if (arguments.length !== 3) {
		alert("missing arguments for findText");
		return;
	}
	var TAo = document.getElementById(Oid);
	var chng_id = document.getElementById(chng);
	Pta.findr.findText(Oid, targ);
	var p1, p2;
	var sels = TAo.selectionStart, sele = TAo.selectionEnd, txt = TAo.value;
	if (sels === sele) {
		alert("No More to replace");
		return;
	}
	p1 = txt.slice(0, sels);
	p2 = txt.slice(sele);
	txt = p1 + chng_id.value + p2;
	TAo.value = txt;
	TAo.selectionStart = txt.length - p2.length;
	TAo.selectionEnd =	txt.length - p2.length;
	TAo.focus();
}, replaceAll:function(Oid, targ, chng) {
	if (arguments.length !== 3) {
		alert("missing arguments for findText");
		return;
	}
	var TAo = document.getElementById(Oid);
	var targ_id = document.getElementById(targ);
	var chng_id = document.getElementById(chng);
	var txt = TAo.value;
	TAo.value = txt.replace(new RegExp(targ_id.value, "g"), chng_id.value);
	TAo.focus();
}, adjustScroll:function(Oid, lh) {
	var inx, c = 0, p = 0, txt;
	var TAo = document.getElementById(Oid);
	txt = TAo.value;
	p = TAo.selectionEnd;
	for (inx = 0;inx < p; inx+=1) {
		if (txt.charAt(inx) === "\n") {
			c+=1;
		}
	}
	TAo.scrollTop = c * lh;

}};	// END of Pta.findr

Pta.insClip =	function (Oid, itext) {
	var TAo = document.getElementById(Oid);
	var tav = TAo.value;
	var strPos = TAo.selectionStart;
	var front = tav.slice(0, strPos);
	var back = tav.slice(strPos);
	TAo.value = front + itext + back;
	TAo.selectionEnd = strPos + itext.length;
	TAo.focus();
};

Pta.countNewLines = function (txt) {
	var inx, c = 0;
	for (inx = 0;inx < txt.length; inx+=1) {
		if (txt.charAt(inx) === "\n") {
			c+=1;
		}
	}
	return c;
};