-- CFrame.lua
local _;
local unpack, pairs, ipairs = unpack, pairs, ipairs;
local ssub = string.sub;
local min = math.min;
local UnitName, UnitClass = UnitName, UnitClass;
local UnitInRange, UnitDebuff, UnitIsCharmed = UnitInRange, UnitDebuff, UnitIsCharmed;
local UnitPower, UnitPowerMax, UnitPowerType = UnitPower, UnitPowerMax, UnitPowerType;
local UnitHealth, UnitHealthMax = UnitHealth, UnitHealthMax;
local UnitInParty, UnitInRaid = UnitInParty, UnitInRaid;
local UnitGetIncomingHeals, UnitGetTotalAbsorbs = UnitGetIncomingHeals, UnitGetTotalAbsorbs;
local UnitThreatSituation, GetThreatStatusColor = UnitThreatSituation, GetThreatStatusColor;
local UnitIsDeadOrGhost, UnitIsConnected = UnitIsDeadOrGhost, UnitIsConnected;
local UnitHasIncomingResurrection = UnitHasIncomingResurrection;
local UnitGetTotalHealAbsorbs = UnitGetTotalHealAbsorbs;
local IsInGroup, IsInRaid = IsInGroup, IsInRaid;
local CTimerAfter = C_Timer.After;
local RAID_CLASS_COLORS = RAID_CLASS_COLORS;

local Frames = OmaFrames;
local Indicators = OmaIndicators;
local checkIndicators = Indicators.CheckIndicators;

local CFrame = CreateFrame("Frame", "OmaCFrame", UIParent);
local party = {};
local raid = {};
local updaters = {};

local width, height = Frames.Width, Frames.Height;
local anchorX, anchorY = Frames.AnchorX, Frames.AnchorY;
local baseColor = Frames.BaseColor;
local overlayColorDispel = Frames.OverlayColorDispel;
local overlayColorCharm = Frames.OverlayColorCharm;
local overlayColorAlert = Frames.OverlayColorAlert;
local powerColors = Frames.PowerColors;

local function updateHealth(frame, unit)
    local current, max = UnitHealth(unit), frame.health.max;
    local healthLost = max - current;
    -- sanity check, occasionally UnitHealthMax gives zero
    if max > 0 then
        frame.health:SetWidth(current/frame.health.max*width);
    else
        frame.health:SetWidth(width);
        frame.text:Hide();
        return;
    end

    if UnitIsDeadOrGhost(unit) then
        frame.health:SetWidth(1);
        if UnitHasIncomingResurrection(unit) then
            frame.text:SetText("Rez");
        else
            frame.text:SetText("Dead");
        end
    elseif not UnitIsConnected(unit) then
        frame.health:SetWidth(1);
        frame.text:SetText("DC");
    elseif healthLost > 0 then
        if healthLost > 1200000000 then -- 1.2B
            frame.text:SetFormattedText("-%.1fB", healthLost / 1000000000);
        elseif healthLost > 1200000 then -- 1.2M
            frame.text:SetFormattedText("-%.1fM", healthLost / 1000000);
        elseif healthLost > 1000 then -- 1K
            frame.text:SetFormattedText("-%dK", healthLost / 1000);
        else
            frame.text:SetFormattedText("-%d", healthLost)
        end
        frame.text:Show();
    else
        frame.text:Hide();
    end
end

local function updateMaxHealth(frame, unit)
    frame.health.max = UnitHealthMax(unit);
    updateHealth(frame, unit);
end

local function updatePower(frame, unit)
    local max = frame.mana.max;
    -- sanity check, occasionally UnitPowerMax gives zero
    if max > 0 then
        frame.mana:SetWidth(UnitPower(unit)/max*width);
    else
        frame.mana:SetWidth(width);
    end
end

local function updateMaxPower(frame, unit)
    frame.mana.max = UnitPowerMax(unit);
    updatePower(frame, unit);
end

local function updatePowerColor(frame, unit)
    frame.mana:SetColorTexture(unpack(powerColors[UnitPowerType(unit)]));
end

local function updateName(frame, unit)
    local name = UnitName(unit);
    if not name then return end
    frame.name:SetText(ssub(name, 1, 6));

    local _, class = UnitClass(unit);
    local color = RAID_CLASS_COLORS[class];
    if color then frame.name:SetVertexColor(color.r, color.g, color.b) end
end

local function updateHealPred(frame, unit)
    local incoming = UnitGetIncomingHeals(unit) or 0;
    if incoming > 0 then
        local max = frame.health.max;
        local space = width - frame.health:GetWidth() + 1;
        local pred = (incoming / max) * width;
        frame.healpred:SetWidth(min(space, pred));
        frame.healpred:Show();
    else
        frame.healpred:Hide();
    end
end

local function updateShield(frame, unit)
    local shield = UnitGetTotalAbsorbs(unit) or 0;
    if shield > 0 then
        local max = frame.health.max;
        local space = width - frame.health:GetWidth();
        shield = (shield / max) * width;
        if space < shield then
            frame.shield:SetWidth(space);
            frame.shieldhl:Show();
        else
            frame.shield:SetWidth(shield);
            frame.shieldhl:Hide();
        end
        frame.shield:Show();
    else
        frame.shield:Hide();
        frame.shieldhl:Hide();
    end
end

local function updateHealAbsorb(frame, unit)
    local absorb = UnitGetTotalHealAbsorbs(unit) or 0;
    if absorb > 0 then
        local max = frame.health.max;
        local space = frame.health:GetWidth();
        absorb = (absorb / max) * width;
        frame.healabsorb:SetWidth(min(space, absorb));
        frame.healabsorb:Show();
    else
        frame.healabsorb:Hide();
    end
end

local function updateAuras(frame, unit)
    checkIndicators(frame, unit);
    if UnitDebuff(unit, 1, "RAID") ~= nil then
        -- something dispellable
        if frame.overlay.color ~= overlayColorDispel then
            frame.overlay:SetColorTexture(unpack(overlayColorDispel));
            frame.overlay:Show();
            frame.overlay.color = overlayColorDispel;
        end
    elseif UnitIsCharmed(unit) then
        if frame.overlay.color ~= overlayColorCharm then
            frame.overlay:SetColorTexture(unpack(overlayColorCharm));
            frame.overlay:Show();
            frame.overlay.color = overlayColorCharm;
        end
    else
        if frame.overlay.color ~= nil then
            frame.overlay:Hide();
            frame.overlay.color = nil;
        end
    end
end

local function updateAggro(frame, unit)
    local status = UnitThreatSituation(unit);
    if status and status > 0 then
        frame.base:SetColorTexture(GetThreatStatusColor(status));
    else
        frame.base:SetColorTexture(unpack(baseColor));
    end
end

local eventFuncs = {
    ["UNIT_HEALTH"] = function(frame, unit)
        updateHealth(frame, unit);
        updateShield(frame, unit);
        updateHealAbsorb(frame, unit);
        -- no heal prediction update, that doesn't overflow too much
    end,
    ["UNIT_POWER"] = function(frame, unit)
        updatePower(frame, unit);
    end,
    ["UNIT_AURA"] = function(frame, unit)
        updateAuras(frame, unit);
    end,
    ["UNIT_HEAL_PREDICTION"] = function(frame, unit)
        updateHealPred(frame, unit);
    end,
    ["UNIT_ABSORB_AMOUNT_CHANGED"] = function(frame, unit)
        updateShield(frame, unit);
    end,
    ["UNIT_HEAL_ABSORB_AMOUNT_CHANGED"] = function(frame, unit)
        updateHealAbsorb(frame, unit);
    end,
    ["UNIT_THREAT_SITUATION_UPDATE"] = function(frame, unit)
        updateAggro(frame, unit);
    end,
    ["UNIT_MAXHEALTH"] = function(frame, unit)
        updateMaxHealth(frame, unit);
    end,
    ["UNIT_MAXPOWER"] = function(frame, unit)
        updateMaxPower(frame, unit);
    end,
    ["UNIT_DISPLAYPOWER"] = function(frame, unit)
        updatePowerColor(frame, unit);
    end,
    ["UNIT_NAME_UPDATE"] = function(frame, unit)
        updateName(frame, unit);
    end,
    ["UNIT_CONNECTION"] = function(frame, unit)
        updateHealth(frame, unit);
    end,
    ["INCOMING_RESURRECT_CHANGED"] = function(frame, unit)
        -- TODO have an icon
        updateHealth(frame, unit);
    end,
    ["PARTY_MEMBER_ENABLE"] = function(frame)
        -- new power info possibly (FrameXML/CompactUnitFrame.lua)
        updateMaxPower(frame, frame.unit);
        updatePowerColor(frame, frame.unit);
    end,
    ["UPDATE_ALL_BARS"] = function(frame, unit)
        updateMaxHealth(frame, unit);
        updateMaxPower(frame, unit);
        --updateHealth(frame, unit); -- MaxHealth covers this
        --updatePower(frame, unit); -- MaxPower covers this
        updateAuras(frame, unit);
        updateShield(frame, unit);
        updateHealPred(frame, unit);
        updateHealAbsorb(frame, unit);
        updatePowerColor(frame, unit);
        updateAggro(frame, unit);
        updateName(frame, unit);
    end,
};
eventFuncs["UNIT_HEALTH_FREQUENT"] = eventFuncs["UNIT_HEALTH"];
eventFuncs["PARTY_MEMBER_DISABLE"] = eventFuncs["PARTY_MEMBER_ENABLE"];
local function unitEvent(self, event, ...)
    local arg1, arg2, arg3, arg4 = ...;
    eventFuncs[event](self, arg1);
end

local function unitUpdate(self, elapsed)
    -- there's no in/out of range event, have to check each frame
    -- from FrameXML/CompactUnitFrame.lua
    local inRange, checked = UnitInRange(self.unit);
    if checked and not inRange then
        self:SetAlpha(0.55);
    else
        self:SetAlpha(1);
    end
end

local function registerEvents(frame, unit)
    -- events are taken from FrameXML/CompactUnitFrame.lua
    -- TODO vehicle support, ready check support, raid marker support,
    -- player flags support (/afk, /dnd)
    -- TODO only update for vehicle events here
    frame:RegisterEvent("PARTY_MEMBER_ENABLE");
    frame:RegisterEvent("PARTY_MEMBER_DISABLE");
    frame:RegisterUnitEvent("UNIT_HEALTH", unit);
    frame:RegisterUnitEvent("UNIT_HEALTH_FREQUENT", unit);
    frame:RegisterUnitEvent("UNIT_MAXHEALTH", unit);
    frame:RegisterUnitEvent("UNIT_POWER", unit);
    frame:RegisterUnitEvent("UNIT_MAXPOWER", unit);
    frame:RegisterUnitEvent("UNIT_DISPLAYPOWER", unit);
    frame:RegisterUnitEvent("UNIT_NAME_UPDATE", unit);
    frame:RegisterUnitEvent("UNIT_AURA", unit);
    frame:RegisterUnitEvent("UNIT_HEAL_PREDICTION", unit);
    frame:RegisterUnitEvent("UNIT_ABSORB_AMOUNT_CHANGED", unit);
    frame:RegisterUnitEvent("UNIT_HEAL_ABSORB_AMOUNT_CHANGED", unit);
    frame:RegisterUnitEvent("UNIT_THREAT_SITUATION_UPDATE", unit);
    frame:RegisterUnitEvent("UNIT_CONNECTION", unit);
    frame:RegisterUnitEvent("INCOMING_RESURRECT_CHANGED", unit);
end

local function vis(frame, vis)
    if vis then
        frame:Show();
        frame:SetScript("OnUpdate", unitUpdate);
        --frame:UnregisterAllEvents();
        --registerEvents(frame, frame.unit);
        -- wait one frame to update data
        -- create function if needed to pass arguments to unitEvent
        local func = updaters[frame];
        if not func then
            func = function() unitEvent(frame, "UPDATE_ALL_BARS", frame.unit) end;
            updaters[frame] = func;
        end
        CTimerAfter(0.01, func);
    else
        frame:Hide();
        frame:SetScript("OnUpdate", nil);
        --frame:UnregisterAllEvents();
    end;
end

local function updateGroup()
    if IsInGroup() then
        if IsInRaid() then
            -- show raid
            for _, val in ipairs(raid) do
                if UnitInRaid(val.frame.unit) then
                    vis(val.frame, true);
                elseif val.frame:IsShown() then
                    vis(val.frame, false);
                end
            end
            -- hide player + party (use pairs, not ipairs)
            for _, val in pairs(party) do
                if val.frame:IsShown() then vis(val.frame, false) end
            end
        else
            -- show player + party
            for _, val in pairs(party) do
                if UnitInParty(val.frame.unit) then
                    vis(val.frame, true);
                elseif val.frame:IsShown() then
                    vis(val.frame, false);
                end
            end
            -- hide raid
            for _, val in ipairs(raid) do
                if val.frame:IsShown() then vis(val.frame, false) end
            end
        end
    else
        -- show player
        vis(party[0].frame, true);
        -- hide all other frames
        for _, val in ipairs(party) do
            if val.frame:IsShown() then vis(val.frame, false) end
        end
        for _, val in ipairs(raid) do
            if val.frame:IsShown() then vis(val.frame, false) end
        end
    end
end

local function initialize()
    CFrame:SetPoint("CENTER", nil, "CENTER", anchorX, anchorY);
    CFrame:SetHeight((height+2)*8);
    CFrame:SetWidth((width+2)*5+1); -- extra pixel for shield overflow
    Frames.InitializeParty(CFrame, party, unitEvent);
    Frames.InitializeRaid(CFrame, raid, unitEvent);
end

CFrame:RegisterEvent("ADDON_LOADED");
CFrame:RegisterEvent("PLAYER_LOGIN");
CFrame:RegisterEvent("PLAYER_ENTERING_WORLD");
CFrame:RegisterEvent("GROUP_ROSTER_UPDATE");
CFrame:RegisterEvent("PLAYER_REGEN_ENABLED");
CFrame:SetScript("OnEvent", function(self, event, ...)
    if event == "GROUP_ROSTER_UPDATE" or event == "PLAYER_REGEN_ENABLED" or
       event == "PLAYER_ENTERING_WORLD" then
        updateGroup();
    elseif event == "PLAYER_LOGIN" then
        initialize();
    elseif event == "ADDON_LOADED" then
        -- loaded
    end
end);