-- List of talent spec displays
local displays = {
    ["DEATHKNIGHT"] = {
        ["Blood"]         = "Blood DK",
        ["Frost"]         = "Frost DK",
        ["Unholy"]        = "Unholy DK",
    },
    ["DRUID"] = {
        ["Balance"]       = "Moonkin",
        ["Feral"]         = "Cat Druid",
        ["Guardian"]      = "Bear Druid",
        ["Restoration"]   = "Resto Druid",
    },
    ["HUNTER"] = {
        ["Beast Mastery"] = "BM Hunter",
        ["Marksmanship"]  = "MM Hunter",
        ["Survival"]      = "Surv Hunter",
    },
    ["MAGE"] = {
        ["Arcane"]        = "Arcane Mage",
        ["Fire"]          = "Fire Mage",
        ["Frost"]         = "Frost Mage",
    },
    ["MONK"] = {
        ["Brewmaster"]    = "Brew Monk",
        ["Mistweaver"]    = "Mist Monk",
        ["Windwalker"]    = "Wind Monk",
    },
    ["PALADIN"] = {
        ["Holy"]          = "Holy Pally",
        ["Protection"]    = "Prot Pally",
        ["Retribution"]   = "Ret Pally",
    },
    ["PRIEST"] = {
        ["Discipline"]    = "Disc Priest",
        ["Holy"]          = "Holy Priest",
        ["Shadow"]        = "Shadow Priest",
    },
    ["ROGUE"] = {
        ["Assassination"] = "Mute Rogue",
        ["Combat"]        = "Combat Rogue",
        ["Subtlety"]      = "Sub Rogue",
    },
    ["SHAMAN"] = {
        ["Elemental"]     = "Ele Shaman",
        ["Enhancement"]   = "Enhance Shaman",
        ["Restoration"]   = "Resto Shaman",
    },
    ["WARLOCK"] = {
        ["Affliction"]    = "Aff Lock",
        ["Demonology"]    = "Demo Lock",
        ["Destruction"]   = "Destro Lock",
    },
    ["WARRIOR"] = {
        ["Arms"]          = "Arms Warr",
        ["Fury"]          = "Fury Warr",
        ["Protection"]    = "Prot Warr",
    },
    ["AMBIGUOUS"] = {
        ["Frost"]         = "Frost Something",
        ["Holy"]          = "Holy Something",
        ["Protection"]    = "Prot Something",
        ["Restoration"]   = "Resto Something",
    },
}

-- List of talent spec roles
local roles = {
    ["DEATHKNIGHT"] = {
        ["Blood"]         = "Tank",
        ["Frost"]         = "Melee",
        ["Unholy"]        = "Melee",
    },
    ["DRUID"] = {
        ["Balance"]       = "Knockback",
        ["Feral"]         = "Melee",
        ["Guardian"]      = "Tank",
        ["Restoration"]   = "Healer",
    },
    ["HUNTER"] = {
        ["Beast Mastery"] = "Knockback",
        ["Marksmanship"]  = "Ranged",
        ["Survival"]      = "Ranged",
    },
    ["MAGE"] = {
        ["Arcane"]        = "Knockback",
        ["Fire"]          = "Ranged",
        ["Frost"]         = "Ranged",
    },
    ["MONK"] = {
        ["Brewmaster"]    = "Tank",
        ["Mistweaver"]    = "Healer",
        ["Windwalker"]    = "Melee",
    },
    ["PALADIN"] = {
        ["Holy"]          = "Healer",
        ["Protection"]    = "Tank",
        ["Retribution"]   = "Melee",
    },
    ["PRIEST"] = {
        ["Discipline"]    = "Healer",
        ["Holy"]          = "Healer",
        ["Shadow"]        = "Ranged",
    },
    ["ROGUE"] = {
        ["Assassination"] = "Melee",
        ["Combat"]        = "Melee",
        ["Subtlety"]      = "Melee",
    },
    ["SHAMAN"] = {
        ["Elemental"]     = "Knockback",
        ["Enhancement"]   = "Melee",
        ["Restoration"]   = "Healer",
    },
    ["WARLOCK"] = {
        ["Affliction"]    = "Knockback",
        ["Demonology"]    = "Knockback",
        ["Destruction"]   = "Knockback",
    },
    ["WARRIOR"] = {
        ["Arms"]          = "Melee",
        ["Fury"]          = "Melee",
        ["Protection"]    = "Tank",
    },
    ["AMBIGUOUS"] = {
        ["Frost"]         = "Ranged", -- Ranged Frost DKs?
        ["Holy"]          = "Healer",
        ["Protection"]    = "Tank",
        ["Restoration"]   = "Healer",
    },
}

-- List of talent spec classes
local classes = {
    ["Blood"]         = "DEATHKNIGHT",
    ["Unholy"]        = "DEATHKNIGHT",
    ["Balance"]       = "DRUID",
    ["Feral"]         = "DRUID",
    ["Guardian"]      = "DRUID",
    ["Beast Mastery"] = "HUNTER",
    ["Marksmanship"]  = "HUNTER",
    ["Survival"]      = "HUNTER",
    ["Arcane"]        = "MAGE",
    ["Fire"]          = "MAGE",
    ["Brewmaster"]    = "MONK",
    ["Mistweaver"]    = "MONK",
    ["Windwalker"]    = "MONK",
    ["Retribution"]   = "PALADIN",
    ["Discipline"]    = "PRIEST",
    ["Shadow"]        = "PRIEST",
    ["Assassination"] = "ROGUE",
    ["Combat"]        = "ROGUE",
    ["Subtlety"]      = "ROGUE",
    ["Elemental"]     = "SHAMAN",
    ["Enhancement"]   = "SHAMAN",
    ["Affliction"]    = "WARLOCK",
    ["Demonology"]    = "WARLOCK",
    ["Destruction"]   = "WARLOCK",
    ["Arms"]          = "WARRIOR",
    ["Fury"]          = "WARRIOR",
    ["Frost"]         = "AMBIGUOUS",
    ["Holy"]          = "AMBIGUOUS",
    ["Protection"]    = "AMBIGUOUS",
    ["Restoration"]   = "AMBIGUOUS",
}

-- List of class colours
local colours = {
    ["DEATHKNIGHT"] = "|cFFC41F3B",
    ["DRUID"]       = "|cFFFF7D0A",
    ["HUNTER"]      = "|cFFABD473",
    ["MAGE"]        = "|cFF69CCF0",
    ["MONK"]        = "|cFF00FF96",
    ["PALADIN"]     = "|cFFF58CBA",
    ["PRIEST"]      = "|cFFFFFFFF",
    ["ROGUE"]       = "|cFFFFF569",
    ["SHAMAN"]      = "|cFF0070DE",
    ["WARLOCK"]     = "|cFF9482C9",
    ["WARRIOR"]     = "|cFFC79C6E",
    ["AMBIGUOUS"]   = "|cFF7F7F7F",
}

local function charcount(s, c)
    local _, n = gsub(s, c, c)
    return n
end

local function charselect(s, i)
    -- Returns false on no character
    local c = strsub(s, i, i)
    return c ~= "" and c
end

local realm = GetRealmName()
local function ParseName(identifier)
    -- Pattern assumes identifier is formatted as "name" or "name-server"
    -- Name is composed of every character except for '-'
    -- Server is any characters after an optional '-' character
    -- When no '-' character is present, the player is from the local realm
    local name, server = strmatch(identifier, "^([^%-]+)-?(.*)")
    return name, server == "" and realm or server
end

local function DisplayMessage(report, message, ...)
    if report then
        SendChatMessage(gsub(message, "%%s", ""), "BATTLEGROUND")
    else
        print(format(message, ...))
    end
end



local function BuildList(side)
    -- Show scores for players of both factions
    RequestBattlefieldScoreData()
    SetBattlefieldScoreFaction()

    -- Build list of players
    local players, specless = {}, 0
    for i = 1, GetNumBattlefieldScores() do
        local identifier, _, _, _, _, faction, race, _, classToken, _, _, _, _, _, _, talentSpec = GetBattlefieldScore(i)
        if faction == side then
            if talentSpec then
                local name, server = ParseName(identifier)
                local player = {
                    ["name"]   = name,
                    ["server"] = server,
                    ["spec"]   = talentSpec,
                }
                -- GetBattlefieldScore occasionally returns nil for race, class, and classToken
                -- Assume all three are absent together
                if race then
                    player["race"]    = race
                    player["class"]   = classToken
                    player["colour"]  = colours[classToken]
                    player["display"] = displays[classToken][talentSpec]
                    player["role"]    = roles[classToken][talentSpec]
                else
                    player["race"]    = "Unknown"
                    player["class"]   = classes[talentSpec]
                    player["colour"]  = colours[classes[talentSpec]]
                    player["display"] = displays[classes[talentSpec]][talentSpec]
                    player["role"]    = roles[classes[talentSpec]][talentSpec]
                end
                tinsert(players, player)
            else
                specless = specless+1
            end
        end
    end

    -- Check for any talented players on the team
    local n = #players
    if n == 0 then
        print(format("%s have 0 players with talents and %d players with no talents.", side == 0 and "Horde" or "Alliance", specless))
        return
    end

    -- Sort by class then spec then name
    sort(players, function(a, b) return a.class == b.class and ( a.spec == b.spec and a.name < b.name or a.spec < b.spec ) or a.class < b.class end)

    return players, n, specless
end

local function DisplaySummary(report)
    DisplayMessage(report, "BG Spy: Team Summary")
    for side = 0, 1 do
        local players, n, specless = BuildList(side)
        if not players then
            return
        end

        -- Role totals
        local total = {
            Tank      = 0,
            Healer    = 0,
            Melee     = 0,
            Ranged    = 0,
            Knockback = 0,
        }

        -- Calculate the role totals
        for i = 1, n do
            total[players[i].role] = total[players[i].role]+1
        end

        -- Display role totals
        DisplayMessage(report, format("%s: %d melee, %d ranged, %d healer%s.%s", side == 0 and "Horde" or "Alliance", total.Tank+total.Melee, total.Ranged+total.Knockback, total.Healer, total.Healer == 1 and "" or "s", specless > 0 and format(" (%d with no talents)", specless) or ""))
    end
end

local function DisplaySpecs(side, report)
    local players, n, specless = BuildList(side)
    if not players then
        return
    end

    -- Role totals
    local total = {
        Tank      = 0,
        Healer    = 0,
        Melee     = 0,
        Ranged    = 0,
        Knockback = 0,
    }

    -- Display list
    local x, last, names = 1, players[1].display, players[1].name
    total[players[1].role] = 1
    local function out(i)
        DisplayMessage(report, format("%dx %%s%s (%s)", x, last, names), players[i].colour)
    end

    for i = 2, n do
        local current = players[i].display
        if current ~= last then
            out(i-1)
            x = 1
            last = current
            names = players[i].name
        else
            x = x+1
            names = format("%s, %s", names, players[i].name)
        end
        total[players[i].role] = total[players[i].role]+1
    end
    out(n)

    -- Display role totals
    DisplayMessage(report, format("%s: %d melee, %d ranged, %d healer%s.%s", side == 0 and "Horde" or "Alliance", total.Tank+total.Melee, total.Ranged+total.Knockback, total.Healer, total.Healer == 1 and "" or "s", specless > 0 and format(" (%d with no talents)", specless) or ""))
end

-- Role listing tables
local member = {
    t = function(role)
        return role == "Tank"
    end,
    h = function(role)
        return role == "Healer"
    end,
    d = function(role)
        return role == "Melee" or role == "Ranged" or role == "Knockback"
    end,
    k = function(role)
        return role == "Knockback"
    end,
}
local listname = {
    t = "tank",
    h = "healer",
    d = "DPS",
    k = "knockback",
}

local function DisplayRole(side, report, list)
    local players, n = BuildList(side)
    if not players then
        return
    end

    -- Display list
    local total = 0
    for i = 1, n do
        if member[list](players[i].role) then
            DisplayMessage(report, format("%s - %s %%s%s", players[i].name, players[i].race, players[i].display), players[i].colour)
            total = total+1
        end
    end
    DisplayMessage(report, format("%s have %d %s%s.", side == 0 and "Horde" or "Alliance", total, listname[list], list ~= "d" and total ~= 1 and "s" or ""))
end

SLASH_BGSPY1, SLASH_BGSPY2 = "/bgspy", "/bgs"
SlashCmdList.BGSPY = function(msg)
    -- Check for any invalid characters
    msg = strlower(msg)
    if not strfind(msg, "[^rfsthdk ]") then

        -- Check for invalid combinations of list types
        local itype = strfind(msg, "[sthdk]") or 0
        if not strfind(msg, "[sthdk]", itype+1) then

            -- Check for repetitions of control characters
            local nf = charcount(msg, "f")
            local nr = charcount(msg, "r")
            if nf <= 1 and nr <= 1 then

                -- Check if player is in a Battleground
                if GetNumBattlefieldScores() == 0 then
                    print("BG Spy: Not in a Battleground.")
                    return
                end

                -- Set the arguments for the list functions
                local side = nf == GetBattlefieldArenaFaction() and 1 or 0
                local report = nr == 1

                -- Run a list function
                local list = charselect(msg, itype)
                if list == "s" then
                    DisplaySpecs(side, report)
                elseif list then
                    DisplayRole(side, report, list)
                else
                    DisplaySummary(report)
                end
                return
            end
        end
    end

    print("BG Spy commands:")
    print("/bgs - Include any additional commands.")
    print("r - Report list to Battleground chat.")
    print("f - List players of friendly team.")
    print("s - List talent spec numbers on team.")
    print("t - List tanks on team.")
    print("h - List healers on team.")
    print("d - List DPS on team.")
    print("k - List players possible of knockback effects on team.")
    print("Example - /bgs rfh - Report friendly healers.")
end