local bCastBars = _G['bCastBars'] or CreateFrame('frame', 'bCastBars', UIParent)
local addonName, ns = ...

local BACKDROP = {
    bgFile = [=[Interface\ChatFrame\ChatFrameBackground]=], insets = {top = -1, bottom = -1, left = -1, right = -1}
}

local castbars = {
    player = true,
    target = true,
    focus = true,
    pet = true,
}

local CastingBarFinishSpell = function(self)
    self.bar:SetStatusBarColor(1,1,1)
    self.fadeOut = 1
    self.casting = nil
    self.channeling = nil
end

local MakeCastBar = function(unit, enable)
    local frame = _G[unit.."bCastBar"] or CreateFrame("frame", unit.."bCastBar", UIParent)
    frame:SetSize(250,20)
    frame:SetBackdrop(BACKDROP)
    frame:SetBackdropColor(0,0,0)
    frame:SetPoint('CENTER', UIParent, 'CENTER')

    local bar = CreateFrame('StatusBar', nil, frame)
    bar:SetStatusBarTexture([=[Interface\ChatFrame\ChatFrameBackground]=])
    bar:SetSize(250,20)
    bar:SetStatusBarColor(.2, .2, .2)
    bar:SetAllPoints()

    local bg = bar:CreateTexture('castbarbgframe', 'BACKGROUND')
    bg:SetTexture([=[Interface\ChatFrame\ChatFrameBackground]=])
    bg:SetVertexColor(.2, .2, .2)
    bg:SetAllPoints()

    local text = bar:CreateFontString(nil, 'OVERLAY')
    text:SetFont([=[Interface\AddOns\oUF_P3lim\pixel.ttf]=], 11, 'OUTLINE')
    text:SetPoint('CENTER', bar, 'CENTER')

    local timer = bar:CreateFontString(nil, 'OVERLAY')
    timer:SetFont([=[Interface\AddOns\oUF_P3lim\pixel.ttf]=], 11, 'OUTLINE')
    timer:SetJustifyH('RIGHT')
    timer:SetPoint('RIGHT', bar, 'RIGHT', -3, 0)

    local icon = frame:CreateTexture(nil, 'ARTWORK')
    icon:SetSize(22,22)
    icon:SetPoint('TOPRIGHT', frame, 'TOPLEFT', -1, 1)
    icon:SetPoint('BOTTOMRIGHT', frame, 'BOTTOMLEFT', -1, -1)
    icon:SetTexCoord(.06, .94, .06, .94)

    frame.bar = bar
    bar.timer = timer
    bar.text = text
    frame.icon = icon

    if unit == "player" then
        frame.lag = _G[frame:GetName().."Lag"] or frame.bar:CreateTexture(frame:GetName().."Lag", "BORDER")
        frame.lag:SetPoint("TOPRIGHT")
        frame.lag:SetPoint("BOTTOMRIGHT")
        frame.lag:SetTexture("Interface\\RAIDFRAME\\Raid-Bar-Hp-Fill", "BACKGROUND")
        frame.lag:SetVertexColor(1, 0, 0)
        frame.lag:SetBlendMode("ADD")
    end

    frame.timerUpdate = .1

    frame:RegisterEvent("PLAYER_TARGET_CHANGED")
    frame:RegisterEvent("UNIT_SPELLCAST_START")
    frame:RegisterEvent("UNIT_SPELLCAST_STOP")
    frame:RegisterEvent("UNIT_SPELLCAST_FAILED")
    frame:RegisterEvent("UNIT_SPELLCAST_INTERRUPTED")
    frame:RegisterEvent("UNIT_SPELLCAST_DELAYED")
    frame:RegisterEvent("UNIT_SPELLCAST_CHANNEL_START")
    frame:RegisterEvent("UNIT_SPELLCAST_CHANNEL_UPDATE")
    frame:RegisterEvent("UNIT_SPELLCAST_CHANNEL_STOP")
    frame:RegisterEvent("UNIT_SPELLCAST_INTERRUPTIBLE")
    frame:RegisterEvent("UNIT_SPELLCAST_NOT_INTERRUPTIBLE")
    frame:RegisterEvent("PLAYER_ENTERING_WORLD")

    frame.unit = unit
    frame.casting = nil
    frame.channeling = nil
    frame.holdTime = 0
    frame.showCastbar = castbars[unit]
    frame.locked = true
    frame:Hide()

    frame:SetScript("OnShow", function(self)
        if not self.locked then return end
        if self.casting then
            local _, _, _, _, st = UnitCastingInfo(self.unit)
            if st then
                self.value = (GetTime() - (st / 1000))
            end
        else
            local _, _, _, _, _, et = UnitChannelInfo(self.unit)
            if et then
                self.value = ((et / 1000) - GetTime())
            end
        end
    end)

    frame:SetScript("OnEvent", function(self, event, ...)
        local arg1 = ...
        if not self.locked then return end
        local unit = self.unit
        if  event == "PLAYER_ENTERING_WORLD" or event == "PLAYER_TARGET_CHANGED" then
            local spellChannel  = UnitChannelInfo(unit)
            local spellName  = UnitCastingInfo(unit)
            if  spellChannel then
                event = "UNIT_SPELLCAST_CHANNEL_START"
                arg1 = unit
            elseif spellName then
                event = "UNIT_SPELLCAST_START"
                arg1 = unit
            else
                CastingBarFinishSpell(self)
            end
        end

        if arg1 ~= unit then return end

        if event == "UNIT_SPELLCAST_START" then
            local name, _, text, texture, startTime, endTime, _, castID, notInterruptible = UnitCastingInfo(unit)
            if not name then
                self:Hide()
                return
            end

            if self.lag then self.lag:Show() end
            self.value = GetTime() - (startTime / 1000)
            self.maxValue = (endTime - startTime) / 1000
            self.bar:SetMinMaxValues(0, self.maxValue)
            self.bar:SetValue(self.value)
            self.bar.text:SetText(text)
            self.icon:SetTexture(texture)
            self:SetAlpha(1)
            self.holdTime = 0
            self.casting = 1
            self.castID = castID
            self.channeling = nil
            self.fadeOut = nil
            if notInterruptible then
                self.bar:SetStatusBarColor(.65, .1, .1)
            else
                self.bar:SetStatusBarColor(0, .8, 0)
            end
            if self.showCastbar then self:Show() end
        elseif event == "UNIT_SPELLCAST_STOP" or event == "UNIT_SPELLCAST_CHANNEL_STOP" then
            if not self:IsVisible() then
                self:Hide()
            end
            if (self.casting and event == "UNIT_SPELLCAST_STOP" and select(4, ...) == self.castID) or (self.channeling and event == "UNIT_SPELLCAST_CHANNEL_STOP") then
                self.bar:SetValue(self.maxValue)
                if event == "UNIT_SPELLCAST_STOP" then
                    self.casting = nil
                    self.bar:SetStatusBarColor(.8, .8, 0)
                else
                    self.channeling = nil
                end
                self.fadeOut = 1
                self.holdTime = 0
            end
        elseif event == "UNIT_SPELLCAST_FAILED" or event == "UNIT_SPELLCAST_INTERRUPTED" then
            if self:IsShown() and (self.casting and select(4, ...) == self.castID) and not self.fadeOut then
                self.bar:SetValue(self.maxValue)
                self.bar:SetStatusBarColor(.8, .8, 0)
                if event == "UNIT_SPELLCAST_FAILED" then
                    self.bar.text:SetText(FAILED)
                else
                    self.bar.text:SetText(INTERRUPTED)
                end
                if self.lag then self.lag:Hide() end
                self.casting = nil
                self.channeling = nil
                self.fadeOut = 1
                self.holdTime = GetTime()
            end
        elseif event == "UNIT_SPELLCAST_DELAYED" then
            if self:IsShown() then
                local name, _, text, texture, startTime, endTime = UnitCastingInfo(unit)
                if not name then
                    self:Hide()
                    return
                end
                self.value = (GetTime() - (startTime / 1000))
                self.maxValue = (endTime - startTime) / 1000
                self.bar:SetMinMaxValues(0, self.maxValue)
                if not self.casting then
                    self.bar:SetStatusBarColor(0, .8, 0)
                    self.casting = 1
                    self.channeling = nil
                    self.fadeOut = 0
                end
            end
        elseif event == "UNIT_SPELLCAST_CHANNEL_START" then
            local name, _, text, texture, startTime, endTime, isTradeSkill, notInterruptible = UnitChannelInfo(unit)
            if not name then
                self:Hide()
                return
            end

            if self.lag then self.lag:Hide() end

            self.value = (endTime / 1000) - GetTime()
            self.maxValue = (endTime - startTime) / 1000
            self.bar:SetMinMaxValues(0, self.maxValue)
            self.bar:SetValue(self.value)
            self.bar.text:SetText(text)
            self.icon:SetTexture(texture)
            self:SetAlpha(1)
            self.holdTime = 0
            self.casting = nil
            self.channeling = 1
            self.fadeOut = nil

            if notInterruptible then
                self.bar:SetStatusBarColor(.65, .1, .1)
            else
                self.bar:SetStatusBarColor(0, .8, 0)
            end
            if self.showCastbar then self:Show() end
        elseif event == "UNIT_SPELLCAST_CHANNEL_UPDATE" then
          if self:IsShown() then
                local name, _, text, texture, startTime, endTime, isTradeSkill, notInterruptible = UnitChannelInfo(unit)
                if not name then
                    self:Hide()
                    return
                end
                self.value = (endTime / 1000) - GetTime()
                self.maxValue = (endTime - startTime) / 1000
                self.bar:SetMinMaxValues(0, self.maxValue)
                self.bar:SetValue(self.value)
            end
        elseif event == "UNIT_SPELLCAST_INTERRUPTIBLE" then
            self.bar:SetStatusBarColor(0, .8, 0)
        elseif event == "UNIT_SPELLCAST_NOT_INTERRUPTIBLE" then
            self.bar:SetStatusBarColor(.65, .1, .1)
        end
    end)

    frame:SetScript("OnUpdate", function(self, elapsed)

        if not self.bar.timer then return end
        if self.timerUpdate and self.timerUpdate < elapsed then
            if self.casting then
                self.bar.timer:SetText(format("%.1f", max(self.maxValue - self.value, 0)))
            elseif self.channeling then
                self.bar.timer:SetText(format("%.1f", max(self.value, 0)))
            else
                self.bar.timer:SetText("")
            end
            self.timerUpdate = .1
        else
            self.timerUpdate = self.timerUpdate - elapsed
        end

        if self.casting then
            self.value = self.value + elapsed
            if self.value >= self.maxValue then
                self.bar:SetValue(self.maxValue)
                CastingBarFinishSpell(self)
                return
            end
            self.bar:SetValue(self.value)
            if self.unit == "player" then
                local down, up, lag = GetNetStats()
                local castingmin, castingmax = self.bar:GetMinMaxValues()
                local lagvalue = ( lag / 1000 ) / ( castingmax - castingmin )
                if ( lagvalue < 0 ) then lagvalue = 0; elseif ( lagvalue > 1 ) then lagvalue = 1 end
                self.lag:ClearAllPoints()
                self.lag:SetPoint("RIGHT")
                self.lag:SetHeight(self.bar:GetHeight())
                self.lag:SetWidth(self.bar:GetWidth() * lagvalue)
            end
        elseif self.channeling then
            self.value = self.value - elapsed
            if self.value <= 0 then
                CastingBarFinishSpell(self)
                return
            end
            self.bar:SetValue(self.value)
        elseif GetTime() < self.holdTime then
            return
        elseif self.fadeOut then
            self.fadeOut = nil
            self:Hide()
        end
    end)
end

bCastBars:RegisterEvent('PLAYER_TALENT_UPDATE')
bCastBars:RegisterEvent('PLAYER_ENTERING_WORLD')
bCastBars:RegisterEvent('ADDON_LOADED')
bCastBars:SetScript('OnEvent', function(self, event, arg1, ...)
    if (event=='ADDON_LOADED' and arg1 == addonName) or event == 'PLAYER_ENTERING_WORLD' or event=='PLAYER_TALENT_UPDATE' then

        CastingBarFrame.showCastbar = false
        CastingBarFrame:UnregisterAllEvents()
        CastingBarFrame:SetScript("OnUpdate", function() end)

        TargetFrameSpellBar.showCastbar = false
        TargetFrameSpellBar:UnregisterAllEvents()
        TargetFrameSpellBar:SetScript("OnUpdate", function() end)

        FocusFrameSpellBar.showCastbar = false
        FocusFrameSpellBar:UnregisterAllEvents()
        FocusFrameSpellBar:SetScript("OnUpdate", function() end)

        PetCastingBarFrame.showCastbar = false
        PetCastingBarFrame:UnregisterAllEvents()
        PetCastingBarFrame:SetScript("OnUpdate", function() end)

        for unit, enable in pairs(castbars) do
            if enable then
                MakeCastBar(unit, enable)
            end
        end
    end
end)