package sh.sar.basedbank.util

import android.content.Context
import android.graphics.Bitmap
import android.graphics.Color
import android.os.Build
import androidx.appcompat.app.AppCompatActivity
import com.google.android.material.color.DynamicColors
import com.google.android.material.color.DynamicColorsOptions
import sh.sar.basedbank.R

object ThemeHelper {

    const val PRESET_BLUE   = "blue"
    const val PRESET_RED    = "red"
    const val PRESET_GREEN  = "green"
    const val PRESET_CUSTOM = "custom"

    fun isSystemTheme(context: Context): Boolean =
        context.getSharedPreferences("prefs", Context.MODE_PRIVATE)
            .getString("theme", "system") == "system"

    fun getAccentPreset(context: Context): String =
        context.getSharedPreferences("prefs", Context.MODE_PRIVATE)
            .getString("accent_preset", PRESET_BLUE) ?: PRESET_BLUE

    fun getCustomColor(context: Context): Int? {
        val hex = context.getSharedPreferences("prefs", Context.MODE_PRIVATE)
            .getString("accent_custom_color", null) ?: return null
        return try { Color.parseColor(hex) } catch (_: Exception) { null }
    }

    fun presetSeedColor(context: Context, preset: String): Int = when (preset) {
        PRESET_RED -> Color.parseColor("#D32F2F")
        PRESET_GREEN  -> Color.parseColor("#4CAF50")
        PRESET_CUSTOM -> getCustomColor(context) ?: Color.parseColor("#3F65AD")
        else          -> Color.parseColor("#3F65AD")
    }

    fun isPitchBlackEnabled(context: Context): Boolean =
        context.getSharedPreferences("prefs", Context.MODE_PRIVATE)
            .getBoolean("pitch_black", false)

    /**
     * Apply the user-chosen accent theme to the given activity.
     * Must be called BEFORE super.onCreate() so window-level attributes
     * (status bar color, etc.) are resolved from the correct overlay.
     * Has no effect when the theme is set to "system" (dynamic colors are
     * handled by BasedBankApp via DynamicColors.applyToActivitiesIfAvailable).
     */
    fun applyAccent(activity: AppCompatActivity) {
        if (isSystemTheme(activity)) return
        val preset = getAccentPreset(activity)
        val seed = presetSeedColor(activity, preset)
        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.S) {
            val bitmap = Bitmap.createBitmap(1, 1, Bitmap.Config.ARGB_8888)
            bitmap.setPixel(0, 0, seed)
            DynamicColors.applyToActivityIfAvailable(
                activity,
                DynamicColorsOptions.Builder().setContentBasedSource(bitmap).build()
            )
        } else {
            // API < 31: apply a simple style overlay (partial palette, but functional)
            val styleRes = when (preset) {
                PRESET_RED -> R.style.ThemeOverlay_Accent_Orange
                PRESET_GREEN  -> R.style.ThemeOverlay_Accent_Green
                else          -> R.style.ThemeOverlay_Accent_Blue
            }
            activity.theme.applyStyle(styleRes, true)
        }

        val prefs = activity.getSharedPreferences("prefs", Context.MODE_PRIVATE)
        val isDark = prefs.getString("theme", "system") == "dark"
        if (isDark && prefs.getBoolean("pitch_black", false)) {
            activity.theme.applyStyle(R.style.ThemeOverlay_PitchBlack, true)
        }
    }
}