--[[
    All Credit for Datapanel.lua goes to Tuks.
    Tukui = http://www.tukui.org/download.php.
    Edited by Cokedriver.
]]

local Core = LibStub("AceAddon-3.0"):GetAddon("BasicUI")
local Module = Core:NewModule("Datapanel", "AceEvent-3.0")

-- Constants (variables whose values are never altered):
local PLAYER_CLASS = UnitClass("player")
local PLAYER_NAME = UnitName("player")
local PLAYER_REALM = GetRealmName()
local SCREEN_WIDTH = tonumber(string.match(({GetScreenResolutions()})[GetCurrentResolution()], "(%d+)x+%d"))
local TOC_VERSION = select(4, GetBuildInfo())
local GAME_LOCALE = GetLocale()

-- Variables:
local db, currentFightDPS, playerRole
local hexa, hexb = "|cffffffff", "|r" -- not very descriptive names :(

-- Variables that point to frames or other objects:
local MainPanel, LeftPanel, CenterPanel, RightPanel, BGPanel

------------------------------------------------------------------------
-- Local functions

local function RGBToHex(r, g, b)
    if r > 1 then r = 1 elseif r < 0 then r = 0 end
    if g > 1 then g = 1 elseif g < 0 then g = 0 end
    if b > 1 then b = 1 elseif b < 0 then b = 0 end
    return format("|cff%02x%02x%02x", r*255, g*255, b*255)
end

local function HexToRGB(hex)
    local rhex, ghex, bhex = strsub(hex, 1, 2), strsub(hex, 3, 4), strsub(hex, 5, 6)
    return tonumber(rhex, 16), tonumber(ghex, 16), tonumber(bhex, 16)
end

local function ShortValue(v)
    if v >= 1e6 then
        return format("%.1fm", v / 1e6):gsub("%.?0+([km])$", "%1")
    elseif v >= 1e3 or v <= -1e3 then
        return format("%.1fk", v / 1e3):gsub("%.?0+([km])$", "%1")
    else
        return v
    end
end

local function GetTooltipAnchor()
    local _, y = GetCursorPosition()
    if (y * 2) > UIParent:GetHeight() then
        return "ANCHOR_BOTTOM", 1, 3
    else
        return "ANCHOR_TOP", 1, -3
    end
end

------------------------------------------------------------------------
-- Module functions

function Module:OnEnable()
    -- You should fix your DB to use module namespaces properly:
    local db = core.db.profile

    -- This line should not be needed if you're using modules correctly:
    if not db.datapanel.enable then return end

    if db.datapanel.enablepanel then -- How is this different than "enable" ? If the panel is not enabled, what's the point of doing anything else?
        self:CreatePanel() -- factor this giant blob out into its own function to keep things clean
    end

    if db.misc.classcolor then
        local _, class = UnitClass("player")
        local color = (CUSTOM_CLASS_COLORS or RAID_CLASS_COLOR)[class]
        hexa = color.colorStr -- no need to format it yourself, it's already done
    else
        hexa = RGBToHex(db.datapanel.customcolor.r, db.datapanel.customcolor.g, db.datapanel.customcolor.b) -- no need to duplicate the code you already wrote into the function
    end

    -- Rather than hardcode all the possible plugins here just use a nice table that you can add/remove stuff to much more easily. Scroll to the bottom to see it.
    self.plugins = {}
    for name, constructor in pairs(self.pluginConstructors) do
        local position = db.datapanel[name]
        if position and position > 0 then
            local plugin = constructor()
            self.plugins[name] = plugin
            self:PlacePlugin(position, plugin)
        end
    end

    -- no need to make a separate frame to handle events, your module object already does this!
    self:UpdatePlayerRole()
    self:RegisterEvent("PLAYER_SPECIALIZATION_CHANGED", "UpdatePlayerRole")
end

function Module:UpdatePlayerRole()
    local spec = GetSpecialization()
    local specRole = GetSpecializationRole(spec) -- no need for a giant table that must be maintained by hand
    if specRole == "TANK" then
        playerRole = "Tank"
    elseif specRole == "HEALER" then
        playerRole = "Caster"
    elseif specRole == "DAMAGER" then
        if UnitPowerType("player") == SPELL_POWER_MANA then
            playerRole = "Caster"
        else
            playerRole = "Melee"
        end
    else
        playerRole = nil -- no spec
    end
end

function Module:CreateFontString(parent, file, size, flags)
    local fs = parent:CreateFontString(nil, "OVERLAY")
    fs:SetFont(file, size, flags)
    fs:SetJustifyH("LEFT")
    fs:SetShadowColor(0, 0, 0)
    fs:SetShadowOffset(1.25, -1.25)
    return fs
end

function Module:PlacePlugin(position, plugin)
    local left = PanelLeft
    local center = PanelCenter
    local right = PanelRight

    -- Left Panel Data
    if position == 1 then
        plugin:SetParent(left)
        plugin:SetHeight(left:GetHeight())
        plugin:SetPoint('LEFT', left, 30, 0)
        plugin:SetPoint('TOP', left)
        plugin:SetPoint('BOTTOM', left)
    elseif position == 2 then
        plugin:SetParent(left)
        plugin:SetHeight(left:GetHeight())
        plugin:SetPoint('TOP', left)
        plugin:SetPoint('BOTTOM', left)
    elseif position == 3 then
        plugin:SetParent(left)
        plugin:SetHeight(left:GetHeight())
        plugin:SetPoint('RIGHT', left, -30, 0)
        plugin:SetPoint('TOP', left)
        plugin:SetPoint('BOTTOM', left)

    -- Center Panel Data
    elseif position == 4 then
        plugin:SetParent(center)
        plugin:SetHeight(center:GetHeight())
        plugin:SetPoint('LEFT', center, 30, 0)
        plugin:SetPoint('TOP', center)
        plugin:SetPoint('BOTTOM', center)
    elseif position == 5 then
        plugin:SetParent(center)
        plugin:SetHeight(center:GetHeight())
        plugin:SetPoint('TOP', center)
        plugin:SetPoint('BOTTOM', center)
    elseif position == 6 then
        plugin:SetParent(center)
        plugin:SetHeight(center:GetHeight())
        plugin:SetPoint('RIGHT', center, -30, 0)
        plugin:SetPoint('TOP', center)
        plugin:SetPoint('BOTTOM', center)

    -- Right Panel Data
    elseif position == 7 then
        plugin:SetParent(right)
        plugin:SetHeight(right:GetHeight())
        plugin:SetPoint('LEFT', right, 30, 0)
        plugin:SetPoint('TOP', right)
        plugin:SetPoint('BOTTOM', right)
    elseif position == 8 then
        plugin:SetParent(right)
        plugin:SetHeight(right:GetHeight())
        plugin:SetPoint('TOP', right)
        plugin:SetPoint('BOTTOM', right)
    elseif position == 9 then
        plugin:SetParent(right)
        plugin:SetHeight(right:GetHeight())
        plugin:SetPoint('RIGHT', right, -30, 0)
        plugin:SetPoint('TOP', right)
        plugin:SetPoint('BOTTOM', right)
    end
end

function Module:CreatePanel()
    if MainPanel then return end -- already done

    -- These are not "local" here because they're already "local" at the top of the file.
    MainPanel = CreateFrame("Frame", "BasicUI_Datapanel", UIParent)
    PanelLeft = CreateFrame("Frame", nil, MainPanel)
    PanelCenter = CreateFrame("Frame", nil, MainPanel)
    PanelRight = CreateFrame("Frame", nil, MainPanel)
    BGPanel = CreateFrame("Frame", nil, MainPanel)

    -- These are common to all panel styles, so don't duplicate code.
    MainPanel:SetHeight(35)
    MainPanel:SetFrameStrata("LOW")
    MainPanel:SetBackdrop({ bgFile = db.datapanel.background, edgeFile = db.datapanel.border, edgeSize = 25, insets = { left = 5, right = 5, top = 5, bottom = 5 } })
    MainPanel:SetBackdropColor(0, 0, 0, 1)

    -- This section can almost certainly be cleaned up by a huge amount,
    -- but I've already spend enough time on this.
    if db.datapanel.panel == "top" then
        MainPanel:SetPoint("TOP", UIParent, 0, 0)
        MainPanel:SetWidth(SCREEN_WIDTH)
        -- Left Panel
        PanelLeft:SetPoint("LEFT", MainPanel, 5, 0)
        PanelLeft:SetHeight(35)
        PanelLeft:SetWidth(SCREEN_WIDTH / 3)
        PanelLeft:SetFrameStrata("LOW")
        PanelLeft:SetFrameLevel(1)
        -- Center Panel
        PanelCenter:SetPoint("CENTER", MainPanel, 0, 0)
        PanelCenter:SetHeight(35)
        PanelCenter:SetWidth(SCREEN_WIDTH / 3)
        PanelCenter:SetFrameStrata("LOW")
        PanelCenter:SetFrameLevel(1)
        -- Right Panel
        PanelRight:SetPoint("RIGHT", MainPanel, -5, 0)
        PanelRight:SetHeight(35)
        PanelRight:SetWidth(SCREEN_WIDTH / 3)
        PanelRight:SetFrameStrata("LOW")
        PanelRight:SetFrameLevel(1)
        -- Battleground Panel
        BGPanel:SetAllPoints(PanelLeft)
        BGPanel:SetFrameStrata("LOW")
        BGPanel:SetFrameLevel(1)
    elseif db.datapanel.panel == "bottom" then
        MainPanel:SetPoint("BOTTOM", UIParent, 0, 0)
        MainPanel:SetWidth(1200)
        -- Left Panel
        PanelLeft:SetPoint("LEFT", MainPanel, 5, 0)
        PanelLeft:SetHeight(35)
        PanelLeft:SetWidth(1200 / 3)
        PanelLeft:SetFrameStrata("LOW")
        PanelLeft:SetFrameLevel(1)
        -- Center Panel
        PanelCenter:SetPoint("CENTER", MainPanel, 0, 0)
        PanelCenter:SetHeight(35)
        PanelCenter:SetWidth(1200 / 3)
        PanelCenter:SetFrameStrata("LOW")
        PanelCenter:SetFrameLevel(1)
        -- Right panel
        PanelRight:SetPoint("RIGHT", MainPanel, -5, 0)
        PanelRight:SetHeight(35)
        PanelRight:SetWidth(1200 / 3)
        PanelRight:SetFrameStrata("LOW")
        PanelRight:SetFrameLevel(1)
        -- Battleground Panel
        BGPanel:SetAllPoints(PanelLeft)
        BGPanel:SetFrameStrata("LOW")
        BGPanel:SetFrameLevel(1)
    elseif db.datapanel.panel == "shortbar" then
        MainPanel:SetPoint("BOTTOM", UIParent, 0, 0)
        MainPanel:SetWidth(725)
        -- Left Panel
        PanelLeft:SetPoint("LEFT", MainPanel, 5, 0)
        PanelLeft:SetHeight(35)
        PanelLeft:SetWidth(725 / 2)
        PanelLeft:SetFrameStrata("LOW")
        PanelLeft:SetFrameLevel(1)
        -- Right panel
        PanelRight:SetPoint("RIGHT", MainPanel, -5, 0)
        PanelRight:SetHeight(35)
        PanelRight:SetWidth(725 / 2)
        PanelRight:SetFrameStrata("LOW")
        PanelRight:SetFrameLevel(1)
        -- Battleground Panel
        BGPanel:SetAllPoints(PanelLeft)
        BGPanel:SetFrameStrata("LOW")
        BGPanel:SetFrameLevel(1)
    end

    -- I did not include any of your code for moving other frames,
    -- but you would want to include it here, after fixing all of the
    -- parts where you break secure frames by overriding their methods.
end

------------------------------------------------------------------------
-- Panel creation
-- This can be simplified hugely by using a table, instead of a bunch of if/end blocks.

Module.pluginConstructors = {
    armor = function()
        local plugin = CreateFrame("Frame", nil, MainPanel) -- proper parentage
        plugin:EnableMouse(true)

        local text = plugin:CreateFontString(nil, "OVERLAY") -- proper parentage
        text:SetFont(db.media.fontNormal, db.media.fontSize,"THINOUTLINE")
        plugin.text = Text -- important!

        plugin:RegisterEvent("PLAYER_ENTERING_WORLD")
        plugin:RegisterUnitEvent("UNIT_AURA", "player") -- limit UNIT_* events to the player when possible
        plugin:RegisterUnitEvent("UNIT_INVENTORY_CHANGED", "player")
        plugin:SetScript("OnEvent", function(self)
            local _, effectiveArmor = UnitArmor("player")
            self.text:SetFormattedText("%sArmor:|r %s", hexa, effectiveArmor)
            self:SetWidth(self.text:GetStringWidth()) -- important!
        end)

        plugin:SetScript("OnEnter", function(self)
            if UnitAffectingCombat("player") then return end

            local anchor, x, y = GetTooltipAnchor(self)
            GameTooltip:SetOwner(self, GameTooltip:SetOwner(self, anchor, x, y)
            GameTooltip:AddLine("Mitigation by Level:")

            -- Your code for this section does not work properly, because you
            -- only calculated the value of "mitigation" once for level 83, and
            -- then showed that same value for all 4 level lines and the target line.
            -- I didn't update it for you, or include the broken stuff here.

            GameTooltip:Show()
        end)

        plugin:SetScript("OnClick", function(self, button)
            ToggleCharacter("PaperDollFrame")
        end)

        return plugin -- important!
    end,
    -- You can update the rest yourself if you want.
    -- Also, it would be more maintainable to put each plugin in its own file, and add them to this table from there, eg:
    --[[
        local Core = LibStub("AceAddon-3.0"):GetAddon("BasicUI")
        local Module = Core:GetModule("Datapanel")

        Module.pluginConstructors["armor"] = function()
            -- create and return the armor plugin
        end
    ]]
}