From f7f62f41f8ddb6cdfb82872eb44679d5416b1d95 Mon Sep 17 00:00:00 2001
From: Eric Hung <naturalsmen@gmail.com>
Date: Thu, 28 Jul 2016 19:02:36 +0800
Subject: [PATCH] Refactor addZigZag to follow skeleton_TA structure

chartZigZag function is given to create zigzag based on skeleton_TA
structure.
---
 R/addZigZag.R | 101 +++++++++++++++++++++++++++++++++-----------------
 1 file changed, 66 insertions(+), 35 deletions(-)

diff --git a/R/addZigZag.R b/R/addZigZag.R
index 7d18ae6d..b108ed09 100644
--- a/R/addZigZag.R
+++ b/R/addZigZag.R
@@ -8,44 +8,75 @@
 function (change = 10, percent = TRUE, retrace = FALSE, lastExtreme = TRUE, 
     ..., on = -1, legend = "auto") 
 {
-    lchob <- get.current.chob()
-    x <- as.matrix(lchob@xdata)
-    x <- cbind(Hi(x),Lo(x))
-    x <- ZigZag(HL = x, change = change, percent = percent, retrace = retrace, 
-        lastExtreme = lastExtreme)
-    yrange <- NULL
-    chobTA <- new("chobTA")
-    if (NCOL(x) == 1) {
-        chobTA@TA.values <- x[lchob@xsubset]
+    lenv <- new.env()
+    lenv$chartZigZag <- function(x, change, percent, retrace, lastExtreme, ..., on, legend) {
+      xdata <- x$Env$xdata
+      xsubset <- x$Env$xsubset
+      xdata <- cbind(Hi(xdata),Lo(xdata))
+      zigzag <- ZigZag(HL = xdata, change = change, percent = percent, retrace = retrace, 
+                       lastExtreme = lastExtreme)[xsubset]
+      spacing <- x$Env$theme$spacing
+      x.pos <- 1 + spacing * (1:NROW(zigzag) - 1)
+      xlim <- x$Env$xlim
+      ylim <- c(min(zigzag, na.rm=TRUE)*0.975, max(zigzag, na.rm=TRUE)*1.05)
+      theme <- x$Env$theme
+      
+      if(any(is.na(on))) {
+        legend.name <- c(paste(legend, ":"),
+                         paste(format(last(na.omit(zigzag)),nsmall = 3L)))
+        text.col <- c(x$Env$theme$fg, 4)
+        # add inbox color
+        rect(xlim[1], ylim[1], xlim[2], ylim[2], col=theme$fill)
+        # add grid lines and left-side axis labels
+        segments(xlim[1], y_grid_lines(ylim), 
+                 xlim[2], y_grid_lines(ylim), 
+                 col = theme$grid, lwd = x$Env$grid.ticks.lwd, lty = 3)
+        text(xlim[1], y_grid_lines(ylim), y_grid_lines(ylim), 
+             col = theme$labels, srt = theme$srt, 
+             offset = 0.5, pos = 2, cex = theme$cex.axis, xpd = TRUE)
+        # add border of plotting area
+        rect(xlim[1], ylim[1], xlim[2], ylim[2], border=theme$labels)
+        yjust <- 1
+      } else {
+        ylim <- x$get_ylim()[[2]]
+        legend.name <- paste(legend, ":", format(last(na.omit(zigzag)),nsmall = 3L))
+        text.col <- 4
+        yjust <- 1.5
+      }
+      lines(x.pos, zigzag, col = 4, lwd = 4, lend = 2, ...)
+      lc <- xts:::legend.coords("topleft", xlim, ylim)
+      legend(x = lc$x, y = lc$y, 
+             legend = legend.name,
+             text.col = text.col, 
+             xjust = lc$xjust, 
+             yjust = yjust, 
+             bty = "n", 
+             y.intersp=0.95)
     }
-    else chobTA@TA.values <- x[lchob@xsubset, ]
-    chobTA@name <- "chartTA"
+    if(!is.character(legend) || legend == "auto")
+      legend <- gsub("^add", "", deparse(match.call()))
+    mapply(function(name, value) {
+      assign(name, value, envir = lenv)
+    }, names(list(change = change, percent = percent, retrace = retrace, lastExtreme = lastExtreme, ..., on = on, legend = legend)), 
+    list(change = change, percent = percent, retrace = retrace, lastExtreme = lastExtreme, ..., on = on, legend = legend))
+    exp <- parse(text = gsub("list", "chartZigZag", as.expression(substitute(list(x = current.chob(), 
+                                                                                  change = change, percent = percent, retrace = retrace, lastExtreme = lastExtreme, ..., on = on, legend = legend)))), srcfile = NULL)
+    lchob <- current.chob()
+    x <- lchob$Env$xdata
+    xsubset <- lchob$Env$xsubset
+    x <- cbind(Hi(x),Lo(x))
+    zigzag <- ZigZag(HL = x, change = change, percent = percent, retrace = retrace, 
+        lastExtreme = lastExtreme)[xsubset]
+    lchob$Env$zigzag <- zigzag
+    
     if (any(is.na(on))) {
-        chobTA@new <- TRUE
-    }
-    else {
-        chobTA@new <- FALSE
-        chobTA@on <- on
-    }
-    chobTA@call <- match.call()
-    legend.name <- gsub("^add", "", deparse(match.call()))
-    gpars <- c(list(...), list(col = 4, lwd = 3))[unique(names(c(list(col = 4, 
-        lwd = 3), list(...))))]
-    chobTA@params <- list(xrange = lchob@xrange, yrange = yrange, 
-        colors = lchob@colors, color.vol = lchob@color.vol, multi.col = lchob@multi.col, 
-        spacing = lchob@spacing, width = lchob@width, bp = lchob@bp, 
-        x.labels = lchob@x.labels, time.scale = lchob@time.scale, 
-        isLogical = is.logical(x), legend = legend, legend.name = legend.name, 
-        pars = list(gpars))
-    if (is.null(sys.call(-1))) {
-        TA <- lchob@passed.args$TA
-        lchob@passed.args$TA <- c(TA, chobTA)
-        lchob@windows <- lchob@windows + ifelse(chobTA@new, 1, 
-            0)
-        do.call("chartSeries.chob", list(lchob))
-        invisible(chobTA)
+        lchob$add_frame(ylim=c(min(zigzag, na.rm=TRUE)*0.975, 
+                               max(zigzag, na.rm=TRUE)*1.05), asp=1, fixed=TRUE)
+        lchob$next_frame()
     }
     else {
-        return(chobTA)
+      lchob$set_frame(sign(on)*(abs(on)+1L))
     }
+    lchob$replot(exp, env=c(lenv, lchob$Env), expr=TRUE)
+    lchob
 }