-- Copyright Epic Games, Inc. All Rights Reserved.

function main()
    import("core.base.option")
    import("core.project.config")
    import("core.project.project")

    config.load()

    -- Override table: target name -> short name (for targets that don't follow convention)
    local short_name_overrides = {
        ["zenserver-test"] = "integration",
    }

    -- Build test list from targets in the "tests" group
    local available_tests = {}
    for name, target in pairs(project.targets()) do
        if target:get("group") == "tests" and name:endswith("-test") then
            local short = short_name_overrides[name]
            if not short then
                -- Derive short name: "zencore-test" -> "core"
                short = name
                if short:startswith("zen") then short = short:sub(4) end
                if short:endswith("-test") then short = short:sub(1, -6) end
            end
            table.insert(available_tests, {short, name})
        end
    end

    -- Add non-test-group entries that have a test subcommand
    table.insert(available_tests, {"server", "zenserver"})

    table.sort(available_tests, function(a, b) return a[1] < b[1] end)

    -- Handle --list: print discovered test names and exit
    if option.get("list") then
        printf("Available tests:\n")
        for _, entry in ipairs(available_tests) do
            printf("  %-16s -> %s\n", entry[1], entry[2])
        end
        return
    end

    local testname = option.get("run")

    -- Parse comma-separated test names into a set
    local requested = {}
    for token in testname:gmatch("[^,]+") do
        requested[token:match("^%s*(.-)%s*$")] = true
    end

    -- Filter to requested test(s)
    local tests = {}
    local matched = {}

    for _, entry in ipairs(available_tests) do
        local name, target = entry[1], entry[2]
        if requested["all"] or requested[name] then
            table.insert(tests, {name = name, target = target})
            matched[name] = true
        end
    end

    -- Check for unknown test names
    if not requested["all"] then
        for name, _ in pairs(requested) do
            if not matched[name] then
                raise("no tests match specification: '%s'", name)
            end
        end
    end

    if #tests == 0 then
        raise("no tests match specification: '%s'", testname)
    end

    local plat, arch
    if is_host("windows") then
        plat = "windows"
        arch = "x64"
    elseif is_host("macosx") then
        plat = "macosx"
        arch = is_arch("arm64") and "arm64" or "x86_64"
    else
        plat = "linux"
        arch = "x86_64"
    end

    -- Only reconfigure if current config doesn't already match
    if config.get("mode") ~= "debug" or config.get("plat") ~= plat or config.get("arch") ~= arch then
        local toolchain_flag = config.get("toolchain") and ("--toolchain=" .. config.get("toolchain")) or ""
        local sdk_flag = config.get("sdk") and ("--sdk=" .. config.get("sdk")) or ""
        os.exec("xmake config -y -c -m debug -p %s -a %s %s %s", plat, arch, toolchain_flag, sdk_flag)
    end

    -- Build targets we're going to run
    if requested["all"] then
        os.exec("xmake build -y")
    else
        for _, entry in ipairs(tests) do
            os.exec("xmake build -y %s", entry.target)
        end
    end

    local use_junit_reporting = option.get("junit")
    local use_noskip = option.get("noskip")
    local use_verbose = option.get("verbose")
    local repeat_count = tonumber(option.get("repeat")) or 1
    local extra_args = option.get("arguments") or {}
    local junit_report_files = {}

    local junit_report_dir
    if use_junit_reporting then
        junit_report_dir = path.join(os.projectdir(), config.get("buildir"), "reports")
        os.mkdir(junit_report_dir)
    end

    -- Results collection for summary table
    local results = {}
    local any_failed = false

    -- Format a number with thousands separators (e.g. 31103 -> "31,103")
    local function format_number(n)
        local s = tostring(n)
        local pos = #s % 3
        if pos == 0 then pos = 3 end
        local result = s:sub(1, pos)
        for i = pos + 1, #s, 3 do
            result = result .. "," .. s:sub(i, i + 2)
        end
        return result
    end

    -- Center a string within a given width
    local function center_str(s, width)
        local pad = width - #s
        local lpad = math.floor(pad / 2)
        local rpad = pad - lpad
        return string.rep(" ", lpad) .. s .. string.rep(" ", rpad)
    end

    -- Left-align a string within a given width (with 1-space left margin)
    local function left_align_str(s, width)
        return " " .. s .. string.rep(" ", width - #s - 1)
    end

    -- Right-align a string within a given width (with 1-space right margin)
    local function right_align_str(s, width)
        return string.rep(" ", width - #s - 1) .. s .. " "
    end

    -- Format elapsed seconds as a human-readable string
    local function format_time(seconds)
        if seconds >= 60 then
            local mins = math.floor(seconds / 60)
            local secs = seconds - mins * 60
            return string.format("%dm %04.1fs", mins, secs)
        else
            return string.format("%.1fs", seconds)
        end
    end

    -- Parse test summary file written by TestListener
    local function parse_summary_file(filepath)
        if not os.isfile(filepath) then return nil end
        local content = io.readfile(filepath)
        if not content then return nil end
        local ct = content:match("cases_total=(%d+)")
        local cp = content:match("cases_passed=(%d+)")
        local at = content:match("assertions_total=(%d+)")
        local ap = content:match("assertions_passed=(%d+)")
        if ct then
            local failures = {}
            for name, file, line in content:gmatch("failed=([^|\n]+)|([^|\n]+)|(%d+)") do
                table.insert(failures, {name = name, file = file, line = tonumber(line)})
            end
            local es = content:match("elapsed_seconds=([%d%.]+)")
            return {
                cases_total = tonumber(ct),
                cases_passed = tonumber(cp) or 0,
                asserts_total = tonumber(at) or 0,
                asserts_passed = tonumber(ap) or 0,
                elapsed_seconds = tonumber(es) or 0,
                failures = failures
            }
        end
        return nil
    end

    -- Temp directory for summary files
    local summary_dir = path.join(os.tmpdir(), "zen-test-summary")
    os.mkdir(summary_dir)

    -- Run each test suite and collect results
    for iteration = 1, repeat_count do
        if repeat_count > 1 then
            printf("\n*** Iteration %d/%d ***\n", iteration, repeat_count)
        end

        for _, entry in ipairs(tests) do
            local name, target = entry.name, entry.target
            printf("=== %s ===\n", target)

            local suite_name = target
            if name == "server" then
                suite_name = "zenserver (test)"
            end

            local cmd = string.format("xmake run %s", target)
            if name == "server" then
                cmd = string.format("xmake run %s test", target)
            end
            cmd = string.format("%s --duration=true", cmd)

            if use_junit_reporting then
                local junit_report_file = path.join(junit_report_dir, string.format("junit-%s-%s-%s.xml", config.plat(), arch, target))
                junit_report_files[target] = junit_report_file
                cmd = string.format("%s --reporters=junit --out=%s", cmd, junit_report_file)
            end
            if use_noskip then
                cmd = string.format("%s --no-skip", cmd)
            end
            if use_verbose and name == "integration" then
                cmd = string.format("%s --verbose", cmd)
            end
            for _, arg in ipairs(extra_args) do
                cmd = string.format("%s %s", cmd, arg)
            end

            -- Tell TestListener where to write the summary
            local summary_file = path.join(summary_dir, target .. ".txt")
            os.setenv("ZEN_TEST_SUMMARY_FILE", summary_file)

            -- Run test with real-time streaming output
            local test_ok = true
            try {
                function()
                    os.exec(cmd)
                end,
                catch {
                    function(errors)
                        test_ok = false
                    end
                }
            }

            -- Read summary written by TestListener
            local summary = parse_summary_file(summary_file)
            os.tryrm(summary_file)

            if not test_ok then
                any_failed = true
            end

            table.insert(results, {
                suite = suite_name,
                cases_passed = summary and summary.cases_passed or 0,
                cases_total = summary and summary.cases_total or 0,
                asserts_passed = summary and summary.asserts_passed or 0,
                asserts_total = summary and summary.asserts_total or 0,
                elapsed_seconds = summary and summary.elapsed_seconds or 0,
                failures = summary and summary.failures or {},
                passed = test_ok
            })
        end

        if any_failed then
            if repeat_count > 1 then
                printf("\n*** Failure detected on iteration %d, stopping ***\n", iteration)
            end
            break
        end
    end

    -- Clean up
    os.setenv("ZEN_TEST_SUMMARY_FILE", "")
    os.tryrm(summary_dir)

    -- Print JUnit reports if requested
    for test, junit_report_file in pairs(junit_report_files) do
        printf("=== report - %s ===\n", test)
        if os.isfile(junit_report_file) then
            local data = io.readfile(junit_report_file)
            if data then
                print(data)
            end
        end
    end

    -- Print summary table
    if #results > 0 then
        -- Calculate column widths based on content
        local col_suite = #("Suite")
        local col_cases = #("Cases")
        local col_asserts = #("Assertions")
        local col_time = #("Time")
        local col_status = #("Status")

        -- Compute totals
        local total_cases_passed = 0
        local total_cases_total = 0
        local total_asserts_passed = 0
        local total_asserts_total = 0
        local total_elapsed = 0

        for _, r in ipairs(results) do
            col_suite = math.max(col_suite, #r.suite)
            local cases_str = format_number(r.cases_passed) .. "/" .. format_number(r.cases_total)
            col_cases = math.max(col_cases, #cases_str)
            local asserts_str = format_number(r.asserts_passed) .. "/" .. format_number(r.asserts_total)
            col_asserts = math.max(col_asserts, #asserts_str)
            col_time = math.max(col_time, #format_time(r.elapsed_seconds))
            local status_str = r.passed and "SUCCESS" or "FAILED"
            col_status = math.max(col_status, #status_str)

            total_cases_passed = total_cases_passed + r.cases_passed
            total_cases_total = total_cases_total + r.cases_total
            total_asserts_passed = total_asserts_passed + r.asserts_passed
            total_asserts_total = total_asserts_total + r.asserts_total
            total_elapsed = total_elapsed + r.elapsed_seconds
        end

        -- Account for totals row in column widths
        col_suite = math.max(col_suite, #("Total"))
        col_cases = math.max(col_cases, #(format_number(total_cases_passed) .. "/" .. format_number(total_cases_total)))
        col_asserts = math.max(col_asserts, #(format_number(total_asserts_passed) .. "/" .. format_number(total_asserts_total)))
        col_time = math.max(col_time, #format_time(total_elapsed))

        -- Add padding (1 space each side)
        col_suite = col_suite + 2
        col_cases = col_cases + 2
        col_asserts = col_asserts + 2
        col_time = col_time + 2
        col_status = col_status + 2

        -- Build horizontal border segments
        local h_suite = string.rep("-", col_suite)
        local h_cases = string.rep("-", col_cases)
        local h_asserts = string.rep("-", col_asserts)
        local h_time = string.rep("-", col_time)
        local h_status = string.rep("-", col_status)

        local top    = "+" .. h_suite .. "+" .. h_cases .. "+" .. h_asserts .. "+" .. h_time .. "+" .. h_status .. "+"
        local mid    = "+" .. h_suite .. "+" .. h_cases .. "+" .. h_asserts .. "+" .. h_time .. "+" .. h_status .. "+"
        local bottom = "+" .. h_suite .. "+" .. h_cases .. "+" .. h_asserts .. "+" .. h_time .. "+" .. h_status .. "+"
        local vbar   = "|"

        local header_msg = any_failed and "Some tests failed:" or "All tests passed:"
        printf("\n* %s\n", header_msg)
        printf("  %s\n", top)
        printf("  %s%s%s%s%s%s%s%s%s%s%s\n", vbar, center_str("Suite", col_suite), vbar, center_str("Cases", col_cases), vbar, center_str("Assertions", col_asserts), vbar, center_str("Time", col_time), vbar, center_str("Status", col_status), vbar)

        for _, r in ipairs(results) do
            printf("  %s\n", mid)
            local cases_str = format_number(r.cases_passed) .. "/" .. format_number(r.cases_total)
            local asserts_str = format_number(r.asserts_passed) .. "/" .. format_number(r.asserts_total)
            local time_str = format_time(r.elapsed_seconds)
            local status_str = r.passed and "SUCCESS" or "FAILED"
            printf("  %s%s%s%s%s%s%s%s%s%s%s\n", vbar, left_align_str(r.suite, col_suite), vbar, right_align_str(cases_str, col_cases), vbar, right_align_str(asserts_str, col_asserts), vbar, right_align_str(time_str, col_time), vbar, right_align_str(status_str, col_status), vbar)
        end

        -- Totals row
        if #results > 1 then
            local h_suite_eq = string.rep("=", col_suite)
            local h_cases_eq = string.rep("=", col_cases)
            local h_asserts_eq = string.rep("=", col_asserts)
            local h_time_eq = string.rep("=", col_time)
            local h_status_eq = string.rep("=", col_status)
            local totals_sep = "+" .. h_suite_eq .. "+" .. h_cases_eq .. "+" .. h_asserts_eq .. "+" .. h_time_eq .. "+" .. h_status_eq .. "+"
            printf("  %s\n", totals_sep)

            local total_cases_str = format_number(total_cases_passed) .. "/" .. format_number(total_cases_total)
            local total_asserts_str = format_number(total_asserts_passed) .. "/" .. format_number(total_asserts_total)
            local total_time_str = format_time(total_elapsed)
            local total_status_str = any_failed and "FAILED" or "SUCCESS"
            printf("  %s%s%s%s%s%s%s%s%s%s%s\n", vbar, left_align_str("Total", col_suite), vbar, right_align_str(total_cases_str, col_cases), vbar, right_align_str(total_asserts_str, col_asserts), vbar, right_align_str(total_time_str, col_time), vbar, right_align_str(total_status_str, col_status), vbar)
        end

        printf("  %s\n", bottom)
    end

    -- Print list of individual failing tests
    if any_failed then
        printf("\n  Failures:\n")
        for _, r in ipairs(results) do
            if #r.failures > 0 then
                printf("  -- %s --\n", r.suite)
                for _, f in ipairs(r.failures) do
                    printf("    FAILED: %s (%s:%d)\n", f.name, f.file, f.line)
                end
            elseif not r.passed then
                printf("  -- %s --\n", r.suite)
                printf("    (test binary exited with error, no failure details available)\n")
            end
        end
    end

    if any_failed then
        raise("one or more test suites failed")
    end
end