#include "segments.h"
#include "segmentsFile.h"
#include "../common/platform.h"

void Segments_unmapAll(mmu_t *mmu) {
	memory_map_t *map;
	
	//iterate all segments
	while(mmu->length) {
		map=&mmu->segments[0];
		int type=map->info;
		
		//unmap accordingly
		switch(type) {
			case MAPPING_INFO_ram:
				//free the RAM
				free(map->pointer);
				Mmu_removeSegment(mmu, map->pos);
				break;
				
			case MAPPING_INFO_stack:
			case MAPPING_INFO_vram:
				//simply unmap stack and vram
				Mmu_removeSegment(mmu, map->pos);
				break;
				
			case MAPPING_INFO_file:
				//handle files correctly
				Segments_unmapFile(mmu, map->pos);
				break;
			
			default:
				//remove other segments
				Mmu_removeSegment(mmu, map->pos);
		}
	}
}

int Segments_mapRam(mmu_t *mmu, int pos, int len, char access) {
	if(mmu->length>=32) return 0;
	
	//allocate the RAM
	char* ptr=(char*) calloc(len, 1);
	if(!ptr) return 0;
	
	//map it
	if(!Mmu_addSegment(mmu, pos, len, ptr, access, MAPPING_INFO_ram)) {
		free(ptr);
		return 0;
	}
	return 1;
}

void Segments_unmapRam(mmu_t *mmu, int pos) {
	memory_map_t *map;
	
	//iterate all segments
	for(int i=0; i<mmu->length; i++) {
		map=&mmu->segments[i];
		if(map->info==MAPPING_INFO_ram&&map->pos==pos) free(map->pointer);
	}
	
	Mmu_removeSegment(mmu, pos);
}

int Segments_mapVram(mmu_t *mmu, int pos) {
	char* ptr=Graph_getVramAddress();
	return Mmu_addSegment(mmu, pos, VRAM_LENGTH, ptr, MMU_ACCESS_r|MMU_ACCESS_w, MAPPING_INFO_vram);
}

int Segments_mapStack(mmu_t *mmu, stack_t *stack, int pos, char access) {
	int len=sizeof(stack_t);
	return Mmu_addSegment(mmu, pos, len, (char*) stack, access, MAPPING_INFO_stack);
}

int Segments_mapFile(mmu_t *mmu, int fd, int pos, int len, int off, char access) {
	//create and configure the segment
	file_segment_t *segment=malloc(sizeof(file_segment_t));
	if(!segment) return 0;
	fileSegmentInit(segment, fd, off, len, access);
	
	//add it to the MMU
	if(!Mmu_addAbsentSegment(mmu, pos, len, fileSegmentRead, fileSegmentWrite, segment, access, MAPPING_INFO_file)) {
		File_close(fd);
		return 0;
	}
	return 1;
}

void Segments_unmapFile(mmu_t *mmu, int pos) {
	memory_map_t *map;
	
	//iterate all segments
	for(int i=0; i<mmu->length; i++) {
		map=&mmu->segments[i];
		if(map->info==MAPPING_INFO_file&&map->pos==pos) {
			file_segment_t *segment=(file_segment_t*) map->opaque;
#if defined(PC)
			fileSegmentFlush(segment);
#endif
			File_close(segment->fd);
		}
	}
	
	Mmu_removeSegment(mmu, pos);
}