#include "web/page_json.h"

#include <Arduino.h>
#include <string.h>

#include "logic/settings.h"

static const char *const TYPES[] = {"clock", "date", "ha", "text", "countdown", "stopwatch", "image"};
static const char *const ALIGNS[] = {"left", "center", "right"};
static const char *const OVERLAYS[] = {"top", "box", "invert"};
static const char *const LANGUAGES[] = {"nl", "en"};
static const char *const SHOWS[] = {"number", "duration", "time", "map"};
static const char *const UNITS[] = {"s", "min", "h"};

template <size_t N> static int indexOf(const char *const (&names)[N], const char *name)
{
	for (size_t i = 0; i < N; i++)
		if (name && strcmp(names[i], name) == 0)
			return i;
	return -1;
}

static const char *DEGREE_UTF8 = "\xC2\xB0";

static String withDegrees(const char *text)
{
	String s = text;
	s.replace(String(DEGREE_SIGN), DEGREE_UTF8);
	return s;
}

void pageToJson(const DynamicPage &page, JsonObject out)
{
	char time[6];
	JsonArray slots = out["slots"].to<JsonArray>();
	for (int i = 0; i < page.slot_count; i++)
	{
		JsonObject slot = slots.add<JsonObject>();
		formatTime(page.slots[i].start, time);
		slot["start"] = String(time);
		slot["bitmap"] = page.slots[i].bitmap;
	}
	JsonArray elements = out["elements"].to<JsonArray>();
	for (int i = 0; i < page.element_count; i++)
	{
		const PageElement &e = page.elements[i];
		JsonObject o = elements.add<JsonObject>();
		o["type"] = TYPES[(int)e.type];
		o["x"] = e.x;
		o["y"] = e.y;
		o["align"] = ALIGNS[(int)e.align];
		o["overlay"] = OVERLAYS[(int)e.overlay];
		o["font"] = e.font;
		o["format"] = e.format;
		o["language"] = LANGUAGES[(int)e.language];
		o["decimals"] = e.decimals;
		o["text"] = withDegrees(e.text);
		o["suffix"] = withDegrees(e.suffix);
		o["entity"] = e.entity;
		o["attribute"] = e.attribute;
		o["factor"] = e.factor;
		o["scroll_width"] = e.scroll_width;
		o["scroll_speed"] = e.scroll_speed;
		char target[17];
		formatTarget(e.target, target);
		o["target"] = String(target);
		o["show"] = SHOWS[(int)e.show];
		o["input_unit"] = UNITS[e.input_unit];
		o["auto_unit"] = e.auto_unit;
		o["absolute"] = e.absolute;
		o["map"] = withDegrees(e.map);
	}
}

// False when the text does not fit. The degree sign (UTF-8) becomes DEGREE_SIGN.
static bool copyText(JsonVariantConst value, char *out, size_t size)
{
	String text = value | "";
	text.replace(DEGREE_UTF8, String(DEGREE_SIGN));
	if (text.length() >= size)
		return false;
	strcpy(out, text.c_str());
	return true;
}

const char *pageFromJson(JsonVariantConst in, DynamicPage &page)
{
	page = DynamicPage();
	JsonArrayConst slots = in["slots"];
	JsonArrayConst elements = in["elements"];
	if (slots.size() > (size_t)PAGE_SLOTS)
		return "Too many time slots (8 at most)";
	if (elements.size() > (size_t)PAGE_ELEMENTS)
		return "Too many elements (8 at most)";

	for (JsonVariantConst s : slots)
	{
		PageSlot &slot = page.slots[page.slot_count++];
		if (!parseTime(s["start"] | "", slot.start))
			return "Times must look like 08:30";
		if (!copyText(s["bitmap"], slot.bitmap, sizeof(slot.bitmap)))
			return "Bitmap name too long";
	}

	for (JsonVariantConst o : elements)
	{
		PageElement &e = page.elements[page.element_count++];
		int type = indexOf(TYPES, o["type"]), align = indexOf(ALIGNS, o["align"] | "left"),
			overlay = indexOf(OVERLAYS, o["overlay"] | "top"), language = indexOf(LANGUAGES, o["language"] | "nl");
		if (type < 0 || align < 0 || overlay < 0 || language < 0)
			return "Unknown element setting";
		e.type = (ElementType)type;
		e.align = (Align)align;
		e.overlay = (Overlay)overlay;
		e.language = (Language)language;
		// Range checks are in validatePage(); out of range numbers must not wrap
		e.x = constrain(o["x"] | 0, -1000, 1000);
		e.y = constrain(o["y"] | 0, -1000, 1000);
		e.format = constrain(o["format"] | 0, 0, 255);
		e.decimals = constrain(o["decimals"] | (int)DECIMALS_AS_IS, -100, 100);
		e.factor = o["factor"] | 1.0f;
		e.scroll_width = constrain(o["scroll_width"] | 0, 0, 255);
		e.scroll_speed = constrain(o["scroll_speed"] | 8, 0, 255);
		int show = indexOf(SHOWS, o["show"] | "number"), unit = indexOf(UNITS, o["input_unit"] | "s");
		if (show < 0 || unit < 0)
			return "Unknown Home Assistant value setting";
		e.show = (HaShow)show;
		e.input_unit = unit;
		e.auto_unit = o["auto_unit"] | false;
		e.absolute = o["absolute"] | false;
		if (!copyText(o["map"], e.map, sizeof(e.map)))
			return "The list of texts is too long (63 characters)";
		const char *target = o["target"] | "";
		if (e.type == ElementType::Countdown && !parseTarget(target, e.target))
			return "Countdown: enter a date and time";
		if (!copyText(o["font"], e.font, sizeof(e.font)) || !copyText(o["text"], e.text, sizeof(e.text)) ||
			!copyText(o["suffix"], e.suffix, sizeof(e.suffix)) || !copyText(o["entity"], e.entity, sizeof(e.entity)) ||
			!copyText(o["attribute"], e.attribute, sizeof(e.attribute)))
			return "Text too long (32 characters, unit 16, entity 64)";
	}
	return validatePage(page);
}