/*
 * Copyright 2010-2023 JetBrains s.r.o. and Kotlin Programming Language contributors.
 * Use of this source code is governed by the Apache 2.0 license that can be found in the license/LICENSE.txt file.
 */

package org.jetbrains.kotlin.generators.builtins.numbers.primitives

import org.jetbrains.kotlin.generators.builtins.PrimitiveType
import java.io.PrintWriter

class JsPrimitivesGenerator(writer: PrintWriter) : BasePrimitivesGenerator(writer) {

    override fun FileBuilder.modifyGeneratedFile() {
        suppress("NON_ABSTRACT_FUNCTION_WITH_NO_BODY")
        suppress("UNUSED_PARAMETER")
    }

    override fun PropertyBuilder.modifyGeneratedCompanionObjectProperty(thisKind: PrimitiveType) {
        if (this.name in setOf("POSITIVE_INFINITY", "NEGATIVE_INFINITY", "NaN")) {
            annotations += "Suppress(\"DIVISION_BY_ZERO\")"
        }
    }

    override fun ClassBuilder.modifyGeneratedClass(thisKind: PrimitiveType) {
        if (thisKind == PrimitiveType.LONG) {
            annotations += "Suppress(\"NOTHING_TO_INLINE\")"
            primaryConstructor {
                visibility = MethodVisibility.INTERNAL
                parameter {
                    name = "internal val low"
                    type = PrimitiveType.INT.capitalized
                }
                parameter {
                    name = "internal val high"
                    type = PrimitiveType.INT.capitalized
                }
            }
        }
    }

    override fun MethodBuilder.modifyGeneratedCompareTo(thisKind: PrimitiveType, otherKind: PrimitiveType) {
        modifyGeneratedBinaryOperation(thisKind, otherKind)
    }

    override fun MethodBuilder.modifyGeneratedBinaryOperation(thisKind: PrimitiveType, otherKind: PrimitiveType) {
        if (thisKind == PrimitiveType.LONG) {
            if (thisKind == otherKind) {
                val implMethod = when (methodName) {
                    "compareTo" -> "compare"
                    "plus" -> "add"
                    "minus" -> "subtract"
                    "times" -> "multiply"
                    "div" -> "divide"
                    "rem" -> "modulo"
                    else -> error("Unsupported binary operation: $methodName")
                }
                "this.$implMethod(other)".setAsExpressionBody()
            } else {
                modifySignature { isInline = true }
                "this${thisKind.castToIfNecessary(otherKind)}.${methodName}(other${otherKind.castToIfNecessary(thisKind)})".setAsExpressionBody()
            }
        }
    }

    override fun MethodBuilder.modifyGeneratedUnaryOperation(thisKind: PrimitiveType) {
        if (thisKind == PrimitiveType.LONG) {
            when (methodName) {
                "inc" -> "this + 1L"
                "dec" -> "this - 1L"
                "unaryMinus" -> "this.inv() + 1L"
                "unaryPlus" -> {
                    modifySignature { isInline = true }
                    "this"
                }
                else -> error(methodName)
            }.setAsExpressionBody()
        }
    }

    override fun MethodBuilder.modifyGeneratedRangeTo(thisKind: PrimitiveType, otherKind: PrimitiveType, opReturnType: PrimitiveType) {
        if (thisKind != PrimitiveType.LONG) {
            noBody()
        }
    }

    override fun MethodBuilder.modifyGeneratedBitShiftOperators(thisKind: PrimitiveType) {
        if (thisKind == PrimitiveType.LONG) {
            val implMethod = when (methodName) {
                "shl" -> "shiftLeft"
                "shr" -> "shiftRight"
                "ushr" -> "shiftRightUnsigned"
                else -> error(methodName)
            }
            "$implMethod(bitCount)".setAsExpressionBody()
        }
    }

    override fun MethodBuilder.modifyGeneratedBitwiseOperators(thisKind: PrimitiveType) {
        if (thisKind == PrimitiveType.LONG) {
            if (methodName == "inv") {
                "Long(low.inv(), high.inv())".setAsExpressionBody()
            } else {
                "Long(this.low $methodName other.low, this.high $methodName other.high)".setAsExpressionBody()
            }
        }
    }

    override fun MethodBuilder.modifyGeneratedConversions(thisKind: PrimitiveType, otherKind: PrimitiveType) {
        if (thisKind == PrimitiveType.LONG) {
            when (otherKind) {
                PrimitiveType.CHAR,
                PrimitiveType.BYTE,
                PrimitiveType.SHORT -> "low.to${otherKind.capitalized}()"
                PrimitiveType.INT -> "low"
                PrimitiveType.LONG -> "this"
                PrimitiveType.FLOAT -> "toDouble().toFloat()"
                PrimitiveType.DOUBLE -> "toNumber()"
                else -> error("Unsupported type $otherKind for Long conversion")
            }.setAsExpressionBody()
        }
    }

    override fun MethodBuilder.modifyGeneratedEquals(thisKind: PrimitiveType) {
        if (thisKind == PrimitiveType.LONG) {
            "other is Long && equalsLong(other)".setAsExpressionBody()
        }
    }

    override fun MethodBuilder.modifyGeneratedToString(thisKind: PrimitiveType) {
        if (thisKind == PrimitiveType.LONG) {
            "this.toStringImpl(radix = 10)".setAsExpressionBody()
        }
    }

    override fun ClassBuilder.generateAdditionalMethods(thisKind: PrimitiveType) {
        method {
            signature {
                isOverride = true
                methodName = "hashCode"
                returnType = PrimitiveType.INT.capitalized
            }
            if (thisKind == PrimitiveType.LONG) {
                "hashCode(this)".setAsExpressionBody()
            }
        }

        if (thisKind == PrimitiveType.LONG) {
            method {
                additionalComments = """
                    This method is used by JavaScript to convert objects of type Long to primitives.
                    This is essential for the JavaScript interop.
                    JavaScript functions that expect `number` are imported in Kotlin as expecting `kotlin.Number`
                    (in our standard library, and also in user projects if they use Dukat for generating external declarations).
                    Because `kotlin.Number` is a supertype of `Long` too, there has to be a way for JS to know how to handle Longs.
                    See KT-50202
                """.trimIndent()
                annotations += "JsName(\"valueOf\")"
                signature {
                    visibility = MethodVisibility.INTERNAL
                    methodName = "valueOf"
                    returnType = PrimitiveType.DOUBLE.capitalized
                }
                "toDouble()".setAsExpressionBody()
            }
        }
    }
}